Note: Descriptions are shown in the official language in which they were submitted.
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MICROSTRUCTURES FOR DELIVERING A COMPOSITION
CUTANEOUSLY TO SKIN USING ROTATABLE STRUCTURES
TECHNICAL FIELD
The present invention relates generally to systems that deliver a composition
into
skin and is particularly directed to an article of manufacture of the type
which is used to
deliver a composition cutaneously (or subcutaneously) into skin. The invention
is
specifically disclosed as a planar array of microelements that are capable of
lancing the
surface of skin and penetrating the surface of skin to a depth where a
composition can be
efficaciously applied. The article of manufacture is capable of delivering a
composition
from a reservoir attached thereto, or the composition can be applied directly
to skin and
utilized therein in combination with the article of manufacture.
BACKGROUND OF THE INVENTION
Human skin is the largest organ. Aside from the function of regulating skin
temperature, the skin's most important function is to serve as an effective
barrier against
insult of the body by foreign agents, such as toxic substances,
microorganisms, and due to
mechanical injury. Human skin comprises several layers: the outermost is the
stratum
corneum, which comprises dead skin cells and makes up a substantial portion of
the first
protective barrier of the body. Most skin comprises a stratum corneum which is
.15-20
layers of dead cells thick (about 10-20 microns in thickness). However, some
"durable"
skin layers, such as heels or calluses, can comprise a stratum corneum which
is from 100-
150 microns thick. On average, the skin naturally sheds at least one skin
layer each day,
and the first one to four layers of skin may be removed without affecting the
protective
nature of skin or the health thereof. In fact, removing up to four (4) layers
of the stratum
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corneum may provide a skin surface area onto which make-up may be more
uniformly
applied and once applied has a more aesthetically pleasing appearance.
Penetration of the outer layers of skin to deliver a pharmaceutical
composition is a
widely held practice. Typically injections of pharmaceuticals are affected by
subcutaneous delivery, intramuscular delivery, as well as intravenous
delivery. Less
invasive procedures have now been developed and are widely utilized. Among
these
"topical" applications are patches, which are used to provide slow release of
a
composition, such as air and motion sickness compositions, or cigarette
smoking
abatement compositions. However, these patch delivery systems rely on
formulations
that can carry the active ingredients across the skin barrier into the blood
stream.
Therefore, formulation and dosing limitations may provide an encumbrance to
delivery of
a medication or skin benefit composition via patch.
There is, therefore, a long felt need for an article of manufacture that can
be used
to deliver a composition cutaneously (or subcutaneously) to skin.
Specifically, there is
also a need for article that is capable of lancing the surface of skin or is
capable of
penetrating the surface of skin to a depth where a composition can be
efficaciously
applied.
One solution to the above-noted long felt need is a "patch" that contains a
plurality
of microneedles, in which each individual microneedle is designed to puncture
the skin up
to a predetermined distance, which typically is greater than the nominal
thickness of the
stratum corneum layer of skin. Using such microneedle patches provides a great
benefit
in that the barrier properties of the skin can be largely overcome, while at
the same time
the microneedles can be painless and bloodless if they are made to not
penetrate through
the epidermis.
One problem with microneedles is that, first they require a direct pushing
motion
against the skin, which may or may not be of sufficient force to penetrate
completely
through the stratum corneum and, second even when they do penetrate the
stratum
corneum, their efficiency of compelling a fluid (such as a liquid drug or
other active)
though their relatively tiny openings is not great (these microneedles are
usually quite
small in diameter). It would be an improvement to provide a microstructure
(e.g., in the
form of a hand-held patch) that can provide a greater efficiency of flow for
some type of
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fluidic compound through the stratum corneum, and to make it possible for the
microstructure to penetrate the outer skin layers (e.g., the stratum corneum)
by a sliding,
rubbing, or rolling motion that is essentially parallel to the skin surface,
rather than
perpendicular to the skin surface. The sliding/rubbing/rolling motion allows
each
microelement protruding from the substrate (or base) of the microstructure to
make
multiple slits or cuts in the outer layers of the skin, which increases the
permeability of
the skin (i.e., it reduces the skin's barrier properties) at that local area.
SUMMARY OF THE INVENTION
Accordingly, it is an advantage of the present invention to provide a method
and
apparatus that can deliver either a benefit to human skin or deliver a
composition
cutaneously into skin.
It is another advantage of the present invention to provide an article of
manufacture that is capable of lancing the surface of skin, or of penetrating
the surface of
skin to a depth where a composition can be efficaciously applied.
It is a further advantage of the present invention to provide an article of
manufacture that is capable of repeatedly penetrating the skin to a
predetermined depth,
thereby providing a means for delivering a composition to the sub stratum
corneum layer.
It is yet another advantage of the present invention to provide a rotating
microstructure that includes a plurality of microelements that can penetrate
the skin
through at least the stratum corneum layer, and to dispense a fluid through
the openings
created in the stratum corneum.
It is still another advantage of the present invention to provide a
microelement
structure in which there are two half-microelement structures or portions that
are spaced-
apart from one another, and in which an opening in a substrate is formed
therebetween.
Additional advantages and other novel features of the invention will be set
forth in
part in the description that follows and in part will become apparent to those
skilled in the
art upon examination of the following or may be learned with the practice of
the
invention.
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To achieve the foregoing and other advantages, and in accordance with one
aspect
of the present invention, a rotatable microstructure apparatus is provided,
which
comprises: a roller structure which includes a curved substrate and a
plurality of
microelements affixed upon a first surface of the substrate; the plurality of
microelements
being of predetennined sizes and shapes so as to penetrate a stratum comeum
layer of
skin when the microstructure apparatus is placed upon the skin and rolled over
the skin in
at least one predetermined direction.
In accordance with another aspect of the present invention, a method for
reducing
the barrier properties of skin is provided, in which the method comprises the
following
steps: (a) providing a rotatable microstructure having a curved substrate and
a plurality of
microelements that protrude from the curved substrate by at least one
predetermined
protrusion distance; and (b) placing and rolling the rotatable microstructure
on a surface
of skin, wherein the at least one predetermined protrusion distance is
sufficient so that
many of the plurality of microelements penetrate a stratum corneum layer of
the skin.
In accordance with yet another aspect of the present invention, a
microstructure
apparatus is provided, which coinprises: a plurality of microelements affixed
upon a
surface of a substrate, the plurality of microelements being of sizes and
shapes so as to
penetrate skin when placed into contact therewith; wherein at least one of the
microelements comprises: (a) two half-structures that are spaced-apart from
one another,
and (b) an opening in the substrate surface, the opening being positioned
between the two
half-structures.
The present invention relates further relates to embodiments of the article of
manufacture which allows sustained cutaneous delivery of a enhancing
composition,
pharmaceutical composition, or the like.
Still other advantages of the present invention will become apparent to those
skilled in this art from the following description and drawings wherein there
is described
and shown a preferred embodiment of this invention in one of the best modes
contemplated for carrying out the invention. As will be realized, the
invention is capable
of other different embodiments, and its several details are capable of
modification in
various, obvious aspects all without departing from the invention.
Accordingly, the
drawings and descriptions will be regarded as illustrative in nature and not
as restrictive.
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According to a first aspect of the invention, there is provided a rotatable
niicrostructure
apparatus, characterized in that it comprises: a roller structure which
includes a curved substrate which
is detachable froni the roller sti-ucture and a plurality of microelements
affixed upon a first surface of
said substrate; said plurality of nucroelements being of predetermined sizes
and shapes so as to
penetrate a stratum corneum Iayer of skin when said niicrostructure apparatus
is placed upon said skin
and rolled over said skin in at least one predetein~iined direction.
According to a second aspect of the invention, there is provided a method for
reducing the
barrier properties of skin, the method characterized in that it coniprises:
(a) providing a rotatable
microstructure having a curved substrate and a plurality of niicroelenients
that protrude from said
curved substrate by at least one predetermined protrusion distance, the
rotatable microstructure being
attached to a rollable carrier; and (b) placing and rolling the rotatable
microstructure on a surface of
skin, wherein said at least one predeterniined protrusion distance is
sufficient so that many of said
plurality of microelements penetrate a stratum corneuni layer of said skin,
and (c) detaching the curved
substrate and plurality of microelements from the rollable carrier.
According to another aspect of the invention, there is provided a rotatable
microstiucture
apparatus, eharacterized in that it comprises: a roller structure which
includes a curved substrate which
is detachable from the roller structure and a plurality of niicroelements
affixed upon a first surface of
said substrate; said plurality of microelements being of predetermined sizes
and shapes so as to
penetrate a stratum comeuni layer of sldn when said microstructure apparatus
is placed upon said sldn
and rolled over said skin in at least one predetermined direction, wherein the
substrate and plurality of
microelenients are disposable for one-tinle use.
According to a further aspect of the invention, there is provided a rotatable
microstructure
apparatus, characterized in that it coniprises: a roller structure which
includes a curved substrate which
is detachable from the roller structure and a plurality of microelements
affixed upon a first surface of
said substrate; said plurality of microelements being of predeterniined sizes
and shapes so as to
penetrate a stratum corneum layer of skin when said inicrostructure apparatus
is placed upon said skin
and rolled over said skin in at least one predetennuied direction, wherein the
substrate and
microelements are formed as a sheet that is sufficiently flexible to be
wrapped around in the shape of a
cylinder.
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All percentages, ratios and proportions herein are by weight, unless otherwise
specified. All temperatures are in degrees Celsius ( C) unless otherwise
specified. All
documents cited are in relevant part, incorporated herein by reference.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings incorporated in and forming a part of the
specification illustrate several aspects of the present invention, and
together with the
description and claims serve to explain the principles of the invention. In
the drawings:
Figure 1 is a plan view of an array of microelements that are pyramidal in
shape,
as constructed according to the principles of the present invention.
Figure 2 is a perspective view of one of the pyramidal microelements of Figure
1.
Figure 3 is an array of pyramidal microelements as according to Figure 1, with
the
addition of through-holes in the substrate, and channels along the sides of
the
microelements.
Figure 4 is a perspective view of the pyramidal microelements of Figure 3.
Figure 5 is a plan view of an array of microelements that have an overall
cubic
rectangular shape, as constructed according to the principles of the present
invention.
Figure 6 is a perspective view of one of the cubic rectangular microelements
of
Figure 5.
Figure 7 is a plan view of an~ array of the cubic rectangular microelements of
Figure 5 with the addition of through-holes in the substrate.
Figure 8 is a perspective view of one of the cubic rectangular microelements
of
Figure 7.
Figure 9 is a plan view of an array of wedge-shaped microelements, as
constructed
according to the principles of the present invention.
Figure 10 is a perspective view of one of the wedge-shaped microelements of
Figure 9.
Figure 11 is a plan view of an array of the wedge-shaped microelements of
Figure
9 with the addition of through-holes that penetrate through the microelement
and through
or into the substrate.
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Figure 12 is a perspective view of one of the wedge-shaped microelements
having
througli-holes of Figure 11.
Figure 13 is a plan view of an array of wedge-shaped microelements of Figure
9,
in which a through-slot is located in the microelements, which penetrates
through or into
the substrate.
Figure 14 is a perspective view of one of the wedge-shaped microelements
having
the through-slot of Figure 13.
Figure 15 is a plan view of an array of microelements having an elongated
triangular shape, as constructed according to the principles of the present
invention.
Figure 16 is a perspective view of one of the elongated triangular
microelements
of Figure 15.
Figure 17 is a plan view of an array of the elongated triangular
microeleinents of
Figure 15 with the addition of through-holes in the substrate, and elongated
channels
along the surfaces of the triangular microelements.
Figure 18 is a perspective view of one of the elongated triangular
microelements
of Figure 17.
Figure 19 is a plan view of an array of triangular-shaped wedge microelements
that are grouped in closely-spaced arrangements, as constructed according to
the
principles of the present invention.
Figure 20 is a perspective view of one of the closely-spaced triangular wedge
microelements of Figure 19.
Figure 21 is a plan view of an array of arcuate-shaped microelements with
wedged
tips, as constructed according to the principles of the present invention.
Figure 22 is a perspective view of one of the wedge, arcuate-shaped
microelements of Figure 21.
Figure 23 is a plan view of an array of the wedge, arcuate-shaped
microelements
of Figure 21 with the addition of through-holes that penetrate through the
microelement
and through or into the substrate.
Figure 24 is a perspective view of one of the wedge, arcuate-shaped,
microelements of Figure 23 having through-holes.
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Figure 25 is a plan view of an array of the wedge, arcuate-shaped
microelements
of Figure 21 in which a through-slot is located in the microelements, which
penetrates
through or into the substrate.
Figure 26 is a perspective view of one of the wedge, arcuate-shaped
microelements of Figure 25 having the through-slot.
Figure 27 is a perspective view of one of the "straight" wedge-shaped
inicroelements 102 as it makes a slit or cut in skin.
Figure 28 is an elevational view in partial cross-section of a wedge-shaped
microelement of Figure 10, in which the side walls are perpendicular with
respect to the
substrate plane.
Figure 29 is an elevational view in partial cross-section of a wedge-shaped
microelement similar to that of Figure 10, in which the side walls have an
angular
relationship that is not perpendicular with respect to the substrate plane.
Figure 30 is an elevational view in partial cross-section of an array of
microelements similar to those found in Figure 23, with the addition of
through-holes or
passageways to a reservoir structure below the main substrate.
Figure 31 is a plan view of a microelement array as seen in Figure 10, with
the
addition of a non-woven backing material that is laminated to the original
substrate.
Figure 32 is a plan view of a plurality of microelement strips that are
laminated
onto a non-woven backing.
Figure 33 is an elevational view in partial cross-section of a microelement
array as
seen in Figure 10, showing further details of the substrate and non-woven
backing.
Figure 34 is perspective view of a microstructure in the shape of a
cylindrical
roller, as constructed according to the principles of the present invention.
Figure 35 is an enlarged perspective view of one of the microelements used in
the
microstructure of Figure 34.
Figure 36 is perspective view of a microstructure in the shape of a
cylindrical
roller, as constructed according to the principles of the present invention.
Figure 37 is an enlarged perspective view of one of the microelements used in
the
microstructure of Figure 36.
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Figure 38 is perspective view of a microstructure in the shape of a
cylindrical
roller, as constructed according to the principles of the present invention.
Figure 39 is an enlarged perspective view of one of the microelements used in
the
microstructure of Figure 38.
Figure 40 shows several more-detailed views of the microelement depicted in
Figure 39.
Figure 41 illustrates two different views of an alternative microelement that
can be
used with the microstructure of Figure 38.
Figure 42 illustrates three views of an alternative microelement that can be
used
with the microstructure of Figure 38.
Figure 43 is a side view in cross-section of a hand-held rolling
microstructure
apparatus for dispensing a fluid into skin, that has a hand-operated
pushbutton for
dispensing the fluid, as constructed according to the principles of the
present invention.
Figure 44 is a perspective view of a roller assembly that contains a
cylindrical
microstructure placed upon skin for dispensing a fluid into skin, as
constructed according
to the principles of the present invention.
Figure 45 is a side view in cross-section of an alternative embodiment of a
hand-
held rolling microstructure apparatus for dispensing a fluid into skin, as
constructed
according to the principles of the present invention.
Figure 46 is a side view in cross-section of an alternative embodiment of a
hand-
held rolling microstructure apparatus for dispensing a fluid into skin, which
uses a
traveling nut to dispense the fluid, as constructed according to the
principles of the
present invention.
Figure 47 is a side view in cross-section of an alternative embodiment for
dispensing fluid from a reservoir using a traveling nut, as constructed
according to the
principles of the present invention.
Figure 48 is a side view in cross-section of a rotatable cylinder with
microelements that dispenses fluid from the interior reservoir of the cylinder
using a
dosing paddle, as constructed according to the principles of the present
invention.
Figure 49 is a side view in cross-section of an alternative embodiment of a
rotatable cylindrical microstructure that can dispense fluid from an interior
reservoir,
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which uses a planetary gear set to move a wiper or dosing paddle, as
constructed
according to the principles of the present invention.
Figure 50 is a perspective view of the cylindrical rotatable dispenser of
Figure 49.
Figure 51 is a perspective view of a cylindrical microstructure that includes
two
sets of threads for tightening the skin as it is being penetrated by
microelements on the
surface of the microstructure, as constructed according to the principles of
the present
invention.
Figure 52 is a side view in partial cross-section of the rotatable cylindrical
dispensing apparatus of Figure 51.
Figure 53 is a perspective view of a microelement that comprises two pyramidal
half-structures, as constructed according to the principles of the present
invention.
Figure 54 is a top view of the microelement of Figure 53.
Figure 55 is a side view in partial cross-section of the microelement of
Figure 53.
Figure 56 is a perspective view of a microelement that comprises two half-
structures having wedge-shaped individual elements, as constructed according
to the
principles of the present invention.
Figure 57 is a top view of the microelement of Figure 56.
Figure 58 is a side view in partial cross-section of the microelement of
Figure 56.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Reference will now be made in detail to the present preferred embodiment of
the
invention, an example of which is illustrated in the accompanying drawings,
wherein like
numerals indicate the same elements throughout the views.
The present invention relates to cutaneous delivery of a composition to the
body
by way of an article of manufacture, which controllably penetrates the outside
layers of
human skin. The present invention further relates to an embodiment wherein the
article
of manufacture remains attached to the skin surface and is capable of
protracted delivery
of a composition, or protracted sampling of a biological' fluid, such as
interstitial fluid.
For the purposes of the present invention the term "cutaneous delivery" is
defined
as "a composition which is controllably delivered to human skin by an article
of
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manufacture wherein the article of manufacture is capable of penetration of
the skin layer
to a finite depth without producing concomitant trauma." The words cutaneous
and
subcutaneous are essentially interchangeable terms as used herein. The term
"trauma" is
defined herein as "pain associated with the application of the article of
manufacture to the
surface of skin, bleeding, bruising, swelling, damage to skin areas, and the
like."
Self-administration of drugs is a necessity for many individuals. Aside from
topically applied medication treating skin itself, most medications are self-
administered
orally. However, there is wide recognition that some categories of
formulations, such as
pharmaceutical formulations, are best administered directly into body tissue,
for example,
intravenous (IV), intramuscular (IM) injections. When applying both IV and IM
injection
techniques, there are a number of considerations. For example, the skill of
administering
person, the will of a patient to self-administer an injection, or the
effectiveness of the
patient's self-delivery must be considered when prescribing a treatment plan.
These issues can be held in abeyance and compositions, pharmaceutical or
otherwise, can be delivered routinely to humans without the concerns of pain,
swelling,
trauma, or lack of compliance by the patient. In addition, the inconvenience
of storing
and re-supplying of syringes, swabs, and the like are made unnecessary by the
systems
and principles of the present invention.
The stratum corneum of skin comprises layers of dead skin cells, which are
part of
the body's protective outer layer. This outermost layer of skin cells can have
a nominal
thickness of from about one hundred (100) microns to about 250 microns for
thick,
durable skin areas, such as calluses, whereas normal, "thin" skin may comprise
from
about ten to about fifteen microns (10-15) thickness for its stratum corneum.
One aspect
of the present invention relates to the penetrating or piercing the stratum
corneum. The
articles of manufacture described herein can be configured to provide various
sizes and
shapes of penetrating microelements. One way this is achieved is by adjusting
the
configuration of the microelements and/or the distance from which the distal
end of the
microelements protrude from a particular base element.
By adjusting the configuration of the penetrating microelements, not only is
the
depth of skin penetration modulated, but also the type of penetration can be
adjusted. For
example, the articles of manufacture of the present invention may have hollow
or grooved
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penetrating microelements, which can serve as passages througli which a
substance may
flow. These passages allow for transport of a composition to the skin, for
example, a
phamlaceutical, preferably without bleeding, pain, or other associated trauma.
The terms
"microelement" and "penetrating microelement" are interchangeable as used
herein.
Articles of Manufacture:
The articles of manufacture of the present invention comprise a base element
(or
"substrate") onto which is affixed or deposed a plurality of microelements.
The following
is a description of the base element and corresponding microelements.
Base Element:
The articles of manufacture of the present invention comprise at least one
base
element having a first side and a second side. Onto the first side are affixed
the
penetrating microelements as described hereinbelow. Aside from providing a
template or
base structure onto which the microelements are affixed, the second side, or
reverse side,
may in turn comprise a handle or other means by which the article of
manufacture can be
held. In another embodiment, a substance can be deposed upon the second side,
which
allows the user to grasp, hold, or otherwise control the motion of the article
using only the
fingertips. The use of a material to provide a tactile surface is especially
compatible for
embodiments wherein the base element comprises a thin, flexible material, such
as paper
or polymeric sheets. One embodiment of the present invention includes base
elements
which comprise flexible sheets, and the thickness of the sheets is determined
by the
desired degree of flexibility. The flexible sheets are typically rigid enough
to provide a
template upon which the microelements can be affixed, but which are easily
deformed to
fit the contours of the skin surface.
The base elements of the present invention may have any shape or
configuration.
For example, one embodiment relates to circular base elements, while another
embodiment relates to rectangular base elements having a width and a length.
For such
articles of manufacture that comprise microelements having a "microelement
angle" less
than 90 as defined hereinbelow, rectangular base elements will have a left
edge and a
right edge. The right edge of the base element is defined herein as the edge
along the
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right side of the base element when the second side of the base element is
facing down
(away from the observer) and the first side is facing the observer. The left
edge is
oppositely defined herein.
In another embodiment of the present invention, the second side may have a
reservoir (or chamber) attached thereto (or constructed therewith) which
contains a
flowable (or "fluidic") composition, or at least one reservoir or chanlber for
receiving
material (e.g., interstitial fluids) removed from skin. For embodiments of
this type, it is
an option to modify the base element to comprise a plurality of hollow
elements, or to
provide channels or pore openings along with solid microelements. Such hollow
elements or channels would ostensibly provide a means for a deliverable
material or
removable material to flow from the first side of the base element to the
second side, or
vice versa. The hollow elements can also be in register with a hollow element,
channel,
hole, or other passageway which modifies the microelements as described
hereinbelow in
a manner that allows a flowable composition to be delivered from the reservoir
through a
hollow element in the base element, through a tube or channel of the
microelement, and
into skin.
For purposes of the present invention, the terms "fluid" or "fluidic" have a
meaning that includes flowable liquids, flowable gases, relatively low-
viscosity creains,
flowable solutions that may contain solid particles, and the like. A "fluidic
compound" or
"fluidic material" specifically includes such liquids, gases, and solutions;
these
compounds or materials may comprise an active, a drug, or a skin conditioner,
or other
useful composition of matter; alternatively, the term "fluidic compound" can
represent at
least two actives, drugs, or the like, including both a biological active and
a chemical
active (in a single fluidic compound).
Penetrating Microelements:
The articles of manufacture of the present invention further comprise a
plurality of
penetrating microelements, which are affixed to the first side or first
surface of the base
element. The "proximal end" of the microelement is defined herein as "the
penetrating
microelement end, which is affixed to or in register witli the base element."
The "distal
end" of the penetrating microelement is defined herein as "the penetrating
microelement
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end which comes into contact with skin, and which is the opposite end of the
microelement from the proximal end." The term "penetrating microelement" is
defined
herein as "an appendage for contacting skin which extends from the first side
of the base
element and is affixed thereto (or protrudes therefrom) at an attachment
angle." The term
" penetrating microelement" refers to the entire element which contacts the
skin and
includes not only the appendage itself, but the attachment angle, any hollow
elements or
grooves, the density of the microelements as measured in the number of
appendages per
square centimeter, and any pre-disposed composition of matter on the
microelement
surface.
The general purpose of the penetrating microelement is to lance, cut, or
otherwise
open the outer layers of skin to a predetermined depth or configuration in
order to deliver
a composition. In one embodiment of the present invention, the penetrating
element is
durable and can, therefore, be reused; however, embodiments which are
disposable are
also encompassed by the present invention, and do not reqqire cleaning or
sterilization
after use.
For the purpose of the present invention the term "lancing" (or "cutting") is
used
herein to define the use of a "penetrating element that has a predetermined
height and
width, wherein the skin is cut to a predetermined limited depth and a
predetermined slit
opening width as even pressure and sliding force is applied by the
microstructure patch to
the skin surface by the user, in which the depth and slit opening width of the
cut made by
the microelement directly corresponds to the skin healing time (i.e., the time
required for
the skin to recover its barrier properties)." Lancing elements are typically
use to penetrate
the easily cut tissue or tissue which is mechanically damaged, for example, an
infected
area of the skin which is tender to the touch or which has scab formation
proximal to the
area to be treated. In addition, penetrating elements which "lance" may be
more suitable
for articles of manufacture that are used to treat skin grafts or tissue
damaged by heat,
such as in first degree or second degree burns.
The term "lancing" typically connotes a single effective stroke, whereas a
"sawtooth" penetrating element is used to penetrate skin that is more durable
and resistant
to mechanical pressure, although such sawtooth motion can also be used on
normal "thin"
skin. Embodiments of the present invention that employ sawtooth motions can be
used in
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"durable areas" of the skin, and include the heel and toe areas, as well as,
calluses, corns, and the like.
V irtually all embodiments of the present invention can be used with either a
single penetrating stroke,
or with a back and forth (or "sawtooth") motion against the surface of skin,
As used herein, the term "rubbing" represents an action by which one of the
microstructures of
the present invention is placed upon skin and moved along the surface of the
skin. The rubbing action
can be achieved manually, or by using a device. In other words, the
microstructure can be held by hand
and manually rubbed against the skin, or the microstructure can be placed on a
mechanical device that
will, in turn, be used to move (or rub) the microstructure upon the surface of
the skin.
The term "skin" is defined herein as "animal skin, including human skin, plant
skin or
surfaces, and even other biological structures that may not have a true "skin"
organ, such as tissue
samples of either plant or animal origin."
For the purposes of the present invention, the term "affixed" as it relates to
attachment of the
microelements to the base element is defined as "held permanently to the first
side of the base
element." Aff=ixed micnoelements are neither removable nor detachable. The
microeiements of the
present invention, as it relates to the term "affixed," can comprise any
suitable embodiment. For
example, the microelements and base element may comprise a single uniform
composition or the
microclcments may be extruded from the material eomprising the first side.
Alternatively, and in a separatc embodiment, the microelements may be applied
to the base
element in a separate operation or manufacturing step, such as lamination to a
non-woven substratc.
Therefore, the microelernents can be fashioned and applied in any manner the
formulator desires
which achieves the desired microelement density or configuration, or which
achieves the desired
penetrating properties. Other suitable microelement configurations include
those described in United
States Patents: US 6,652,478; US 6,931,277; US 6,451,240; and US 6,565,532,
all of which are
commonly-assigned to The Procter & Gamble Company.
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For the purposes of the present invention the term "microelement density" is
defined herein as "the number of microelements per square centimeter of base
element
surface."
The appendages that comprise the microelements may be of any configuration
that
is capable of providing the desired skin penetration necessary to deliver a
composition or
treatment. One embodiment of the present invention relates to a plurality of
appendages
in the form rod-shaped appendages that are either circular or elliptical,
perhaps having a
uniform circumference along the entire length. Planar appendages include cubes
or cubic
rectangles (or open boxes) wherein the length and width are uniform (but not
necessarily
equal to one another) throughout the height of the appendage and the distal
end comprises
a plane, such as a square, rectangle, or trapezoid, in which the plane is
parallel to the base
element or at an angle thereto. Wedge-shaped appendages have a rectangular
proximal
base that tapers to a line segment, which preferably has the saine length as
the length of
the rectangular base. Some wedge-shaped appendages may have an inverted
appearance.
Pyramidal appendages may conlprise bases which have three or four sides at the
proximal
end base, and which taper to a point or rounded top at the distal end.
Alternatively, the
wedge-shaped appendages may have a triangular section removed therefrom that
acts to
facilitate the removal of skin hair follicles. The appendages of the present
invention may
also be coiled or otherwise arcuate, having any number of turns from the
proximal end to
the distal end.
One embodiment of the present invention relates to a plurality of lancing
elements
arranged laterally across the front edge of the base element. Sawtooth-like
embodiments
may have the "teeth" varied in a variety of ways, for example, the size
(height) of the
teeth, the spacing between teeth, and whether the ends of the teeth are
tapered to a more
narrow width. Other penetrating elements include square or rectangular posts,
blades
(circular and straight), straight or curved wedges, or pyramidal-, cylindrical-
, cube-, and
star-shaped elements.
For the purposes of the present invention the term "penetrating element angle"
is
defined as the "angle at which the appendage of the penetrating microelement
protrudes
from the base element." For example, a microelement, which is affixed
perpendicular to
the base element, has a penetrating element angle of 90 . The microelements of
the
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present invention can be affixed to the base element at any angle from about
30 to about
90 (perpendicular). However, if the direction of use of the article of
manufacture is not
symmetrical, the microelements can be affixed to the base element at any angle
from
about 30 to about 150 . In addition, microelements which are not
perpendicular to the
base element may be angled toward any edge of a rectangular or square base
element, or
be perpendicular to the tangent of any point along the circumference of a
circular base
element.
The penetrating microelements of the present invention may also comprise
hollow
elements or contain grooves. Hollow elements are typically disposed along the
longitudinal axis of the appendage portion of the microelement and are in
register with a
corresponding hollow element or passageway at the base element. Grooves or
indented
elements occur along the surface of an appendage and serve, like hollow
elements, to
provide a means for a solution to be delivered into the fissures created by
the penetrating
elements. Embodiments having at least one reservoir or chamber can deliver a
fluidic
compound into the skin.
The microelements of the present invention may range from absolute rigid
(inflexible) to flexible. For the purposes of the present invention, the term
"flexible" is
defined herein as "during use against skin, the distal end of an appendage is
bent or
deformed up to 90 from the microelement angle as defined herein above." A
perpendicular appendage which is bent 90 is therefore parallel with the base
element.
An appendage having a microelement angle of 45 can be deformed or bent to an
angle of
135 . It will be understood, however, that the penetrating microelements that
cut into
skin, as discussed below, are typically non-rigid in nature.
The penetrating elements of the present invention may have a protrusion
distance
of up to 1000 microns from the surface of the base element. The term
"protrusion
distance" is defined herein as "tlie distance from distal end of the
penetrating
microelement along a line parallel to the base element." For perpendicular
microelements
the length of the appendage and the protrusion distance are equivalent. A
microelement
having a microelement angle, for example, of 30 will have a protrusion
distance equal to
one half the length of the appendage.
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One embodiment of the present invention relates to microelements having a
protrusion distance of about 1-1000 microns. Another embodiment relates to
protrusion
distances of about 1-200 microns. Further einbodiments encompass penetrating
microelements wherein the appendages have protrusion distances from about one
to about
twenty (1-20) microns, whereas other embodiments include protrusion distances
of from
about five to about twenty (5-20) microns and from about four to about twenty
(4-20)
microns, as well as embodiments from about four to about ten microns (4-10).
Other
embodiments comprise no range of protrusion distances but have discreet
distances, for
example, a 4-micron embodiment, a 5-micron embodiment, a 10-micron embodiment.
The penetrating microelements of the present invention may comprise an
appendage which has flexible elements and rigid elements such as, for example,
an
appendage which has a rigid portion extending from about the middle of the
element to
the proximal end and a flexible portion extending from about the middle of the
element to
the distal end. Articles of manufacture which are composites of several
materials may
comprise a thin flexible base element onto which are deposed rigid, inflexible
penetrating
elements. As noted above, most of the penetrating microelements described
herein will
be rigid in nature.
The articles of manufacture of the present invention may comprise a multitude
of
arrays, each array comprising the same or different types or sizes of
microelements, in
which the various attributes of the microelements, including microelement
density,
appendage type, microelement angle, hollow elements vs. solid elements with or
without
grooves, degree of flexibility, protrusion distance, etc. may vary from array
to array or
within a single particular array. For the purposes of the present invention
the term "array"
is defined as "multiple microelements in a pattern."
In some cases, certain array elements collectively may be separated from
another
array by a distance which is greater than the distance between the
microelements which
comprise the first array. In other cases, arrays may contain different types
of
microelements which all have the same spacings. The distance between
microelements
along the edge of two separate and distinct arrays may be greater than the
distance
between two microelements, which are members of the same array. Alternatively,
several
different microelement shapes or protrusion sizes may exist in a single array
in which all
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individual elements are spaced-apart from one another in a consistent manner
throughout
the entire structure.
The microelements preferably have a length and shape that will tend to
penetrate
entirely through the stratum comeum layer by a cutting ("lancing"), slitting,
or plowing
motion. The characteristic of the microelements to cut and penetrate entirely
through the
stratum corneum is further enhanced by directing the user to move the "patch"
or
microstructure substantially in only one direction (or substantially along a
single line that
represents a back and forth direction), so that the "sharper" edges of the
microelements
tend to cut or plow into the skin upper layers. This allows a liquid or cream-
like
substance (i.e., a fluidic compound) to be placed into the slits or cuts made
in the stratum
corneum, and greatly enhances the amount of such fluid or cream (e.g., an
active, drug, or
other compound) to enter through the stratum corneum. Furthermore, so long as
the
penetration depth is properly controlled (which is accomplished by providing
microelements having proper shapes and lengths), the skin heals very quickly;
in some
circumstances, the skin's barrier properties recover in less than two hours!
The methodologies for using "solid" microelements are expected by the
inventors
in two main embodiments: (1) first to cut (or "lance") the skin using the
microstructure
(or patch), then apply a fluidic material (such as an active) onto the same
skin area after
withdrawing the microstructure patch, and the fluidic material will tend to
penetrate into
the stratum corneum through the slits just previously made; or (2) first to
apply the fluidic
material onto the skin and then place the microstructure patch upon the same
skin area
and out (or lance) the skin, thereby assisting (or forcing) the fluidic
material to penetrate
through the stratum corneuni.
A further methodology for use involves microelements having holes or slots
therethrough, or through-holes in the substrate adjacent to the microelements.
In this
embodiment of use, the skin is cut ("lanced") and a fluidic material is
applied through the
holes/slots in a single procedural step. Of course, the skin must first
literally be slit or cut
through its stratum corneum layer before the fluidic material can flow through
the slits
formed therein, but this essentially can occur virtually simultaneously while
the user
makes a single back and forth set of movements (or perhaps even a single
stroke in only
one direction would suffice in certain physical configurations of
microstructures). A
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reservoir of some type to hold the fluidic material would be required as part
of the
microstructure patch in this methodology, although there are variations
available as to the
exact construction of such a reservoir, as described below.
Referring now to the drawings, Figure 1 illustrates a microstructure array
generally designated by the reference numeral 10 containing multiple
microelements 12
that are situated on a base or substrate 14. In Figure 1, each "column" of
microelements
is offset from the next, adjacent column of similar microelements. However,
each of
the columns could be made to be identical to one another, if desired, and the
offset could
be removed. Alternatively, there could be several columns with various offsets
before the
10 microelement pattern repeats, or the offsets could be substantially random
so that there is
no repetitive pattern.
Figure 2 illustrates in a magnified view one of the microelements 12, which
has
the appearance of a four-sided pyramid. Each side wall of the pyramid is
designated at
the reference numeral 20, and the seam or "corner" between sides is located at
the
reference numeral 22. The pyramid's peak is illustrated at 24, and the base
line of each of
the sides is located at 26, where it meets the substrate 14.
This array 10 of microelements is very useful in penetrating the stratum
corneum
layer of skin by forming it into a patch that can be held by a human hand, and
placed
against a particular area of skin and then rubbed in a straight back and forth
motion (or
perhaps in a circular motion, if desired). When the patch or array 10 is
rubbed against the
skin, the microelements 12 will tend to penetrate into the dead skin cells,
and will do so
with a lateral, sliding motion (that is substantially parallel to the skin
surface) instead of
using a pushing or thrusting motion (that is basically perpendicular to the
skin surface).
The array or patch 10 will correctly perform its functions of penetrating
through
the stratum corneum without regard to the direction of movement of the patch
10 with
respect to the orientation of the individual microelements 12. In other words,
these
microelements 12 are omnidirectional in operation, and all directions are
preferred, or
even "predetermined." Other embodiments of the invention described below are
not
omnidirectional, and instead are unidirectional or bi-directional in nature
with respect to
the orientation of their individual microelements.
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The microelements will cut into the skin to a predetermined "penetration
depth,"
which will be controlled by (and probably substantially equivalent to) the
"protrusion
distance" of the microelements 12. Other embodiments of the present invention,
as
described below, will function in a like manner.
Another feature of the microstructure 10 is its capability for use in applying
a
conditioner or other type of compound that is in the form of a liquid or a
cream. Just after
the microstructure patch 10 has penetrated an area of skin, the stratum
corneum will have
numerous slits or cuts therewithin, which significantly reduces (at least
temporarily) the
skin's barrier properties. A fluidic compound can now be applied to the skin,
which will
much more readily make the journey into the epidermal layer. The fluidic
compound
could be some type of drug or other active, if desired. The other
microstructures
described below will also lend themselves well for this type of topical
application of a
fluidic compound to penetrate into skin.
A further feature of the microstructure 10 is its capability for a compound to
be
applied onto the substrate 14 and/or microelements 12 in advance of its
placement against
an area of skin. When the microstructure patch 10 is placed onto the skin, it
will impart
some of this compound onto the same area of the skin that is being penetrated-
this will
essentially occur simultaneously. The other microstructures described below
will also
lend themselves well for this type of simultaneous delivery of a fluidic
compound to the
same area of skin that is being penetrated. Of course, the embodiments
described below
which include through-holes in the substrate (e.g., see Figures 3 and 4) may
not be the
first choice for this methodology of composition delivery, but such devices
certainly
could be used in this manner, if desired. The compound that is pre-applied to
the surface
of the microstructure 10 could be placed either by the user, or at the time of
manufacture
of the microstructure 10.
Figure 3 illustrates a similar microelement array, generally designated by the
reference numeral 30, in which through-holes and channels are added. The base
or
substrate 34 includes a plurality of through-holes 36 that are positioned
proximal to the
base of the individual pyramidal microelements 32. These through-holes 36 can
either
penetrate through the entire substrate 34, or can penetrate partially into the
substrate and
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connect to passageways that may run in a direction perpendicular to the
through-holes,
and make common connections between many of the through-holes.
On Figure 4, further details are visible, in which the side walls 40 of the
pyramidal
microelement 32 are seen to have grooved channels 38 which connect to the
through-
holes 36. The edges of the side walls 40 are at reference numeral 42, the
individual base
lines of the pyramid are at 46, and the peak of the pyramid is at 44.
On Figures 3 and 4, the array 30 of multiple pyramidal structures at 32 all
have a
through-hole adjacent to each side of the pyramid. Of course, there could be
fewer
through-holes 36 per pyramidal microelement 32, if desired. Alternatively,
some of the
pyramidal microelements 32 in the array could have no adjacent through-holes,
if desired.
Such microelements (or others in the array) could also forego the channels 38.
The structure of Figures 3 and 4 is useful to perform a simultaneous
penetration
and drug delivery step. While the array or "patch" 30 is rubbed along the
skin, the skin
cells of the stratum corneum will be cut, lanced, or slit (or otherwise
penetrated) by the
individual pyramidal microelements 32, which will prepare the skin for any
type of
fluidic compound that will then be "injected" through that area of skin
surface. A
capillary force will work to the advantage of delivering a drug or other
active. Of course,
mechanical pressure or iontophoresis could be used to assist in the delivery,
for example.
It will be understood that instead of delivery of a fluidic compound such as a
drug
into the skin, the microstructures disclosed in Figures 3 and 4 could be used
to sample an
interstitial fluid, for example. In that event, the fluid flow would of course
be in the
opposite direction through the through-holes 36, and would subsequently be
directed to a
collecting reservoir or chamber, as for example, is described below.
Similar to the patch 10, the array or patch 30 will correctly perform its
functions
of penetrating the skin cells of the stratum corneum without regard to the
direction of
movement of the patch 30 with respect to the orientation of the individual
microelements
32. In other words, these microelements 32 are omnidirectional in operation,
and all
directions are preferred, or even "predetermined."
Another potential use of the array or patch 30 is to attach the entire
microstructure
patch to skin for an relatively lengthy time interval, and thereby provide a
capability for
protracted delivery of the fluidic compound into the epidermis, using the cuts
or slits that
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were formed during the previous rubbing procedure. It also would be possible
to sample
biological fluids for a prolonged time interval by attaching the
microstructure patch to the
skin. Moreover, it would be possible to have simultaneous interstitial fluid
sampling and
drug delivery (of insulin, for example) by this arrangement, particularly if
more than one
set of holes in a microelement were provided (see other such structures,
below), or if at
least two groups of microelements were provided on a single substrate. A first
group (or
array) could sample the interstitial fluid, while a second group (or array)
could delivery
the drug.
Another microelement shape is illustrated in Figure 5, comprising an array 50
of
"cubic rectangular" microelements at 52. These microelements 52 have a cup-
like shape
which has the appearance of a topless, hollow or open cube-like or box-like
structure after
one of the cube's (box's) side walls have been removed. This can be clearly
seen in the
perspective view of Figure 6. (It will be understood that the "cube-like
structure" 52 does
not have identical length, width, and height outer dimensions, and thus is not
really a
geometric cube. In that respect, the term "box-like" or "box" is more
descriptive.)
The individual columns of microelements 52 can be offset on the substrate 54,
as
seen in Figure 5. As an alternative construction, each of the individual
columns of these
microelements 52 could be identical, thereby eliminating any offset, if
desired. As a
further alternative, there could be several columns with various offsets
before the
microelement pattern repeats, or the offsets could be substantially random so
that there is
no repetitive pattern.
Figure 6 shows further details of the individual microelement 52, which has a
"back wall" 62, a pair of "side walls" 60, a "front edge" at 64 on each of the
side walls 60,
and a base line 66 along the bottom of the side walls 60.
To penetrate the stratum corneum of skin, the microstructure or "patch" 50 is
rubbed back and forth substantially along the direction designated by the
letter "C"
(which is a preferred, predetermined direction). In this manner, the edges at
64 will cut or
lance through the skin cells to a predetermined penetration depth, which will
be
substantially equivalent to the protrusion distance of the microelements 52.
Figure 7 illustrates a similar array of microelements, designated by the
reference
numeral 70. Each individual microelement 72 has a similar appearance to the
open box-
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like microelements 52 of Figures 5 and 6, however, a through-hole 76 has been
added
within the "cup-like" area of the microelement 72. These holes typically would
run
completely through the base or substrate 74, although they could instead
extend only
partially into the substrate to connect to some type of internal channels. In
that manner,
these holes could become (or connect to) passageways of any shape, diameter,
or length.
The microstructure array 70 could be formed into a "patch" that is applied to
skin
and rubbed in a back and forth manner substantially in the direction "C"
indicated on
Figure 7 (which is a preferred, predetermined direction). Figure 8 shows
further details,
in which there are two side walls 80, a back wall 82, two "front" edges 84, a
base line 86
for each of the side walls 80, and the through-hole 76 that is proximal to the
interior area
of the microelement 72. In a similar manner to the previously described
microstructure of
Figures 3 and 4, the microstructure 70 disclosed on Figures 7 and 8 can be
used to
simultaneously penetrate the skin surface while delivering some type of active
into the
epidermis. Such systems can both penetrate the skin's outer layer and deliver
to the
epidermis in a single operation by a user.
Figure 9 illustrates an array 100 of wedge-shaped microelements 102 mounted
onto a base or substrate 104. As in some of the earlier-described embodiments,
each
column of microelements 102 can be offset from the adjacent column, as
illustrated on
Figure 9. However, the columns could alternatively be made identical to one
another, in
which there would be no offset. A further alternative could arrange several
columns with
various offsets before the microelement pattern repeats, or the offsets could
be
substantially random so that there is no repetitive pattern.
The wedge-shaped microelement 102 is illustrated in greater detail in the.
perspective view of Figure 10. The top of the structure is at 114, and there
are two
elongated side walls 112 and a pair of converging side walls 110 that, at
their line of
convergence, form a cutting edge 116. There is also a base line 118 at the
junction
between the side wall 110 and the substrate 104.
The relatively sharp edge 116 is purposefully used to cut or slit (or "lance")
the
skin in the methodology described in this patent document. The overall wedge
shape of
the microelement 102 is provided as a more substantial structure than some of
the other
embodiments described herein. It also is probably easier to manufacture than
the
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microelements described earlier, in Figures 1-8. In the microelements of the
array 100 on
Figure 9, it is preferred to apply the array as a "patch" onto skin, and then
rub it in a back
and forth manner substantially along the line "C" (which is a preferred,
predetermined
direction). As can be seen from Figure 9, the relatively sharp edges 116 will
be used to
cut into the skin when the patch 100 is moved in this manner along the line
"C".
In essence, the edge 116 will tend to act as a miniature plow against the dead
skin
cells of the stratum corneum. A more descriptive view of the plowing action is
provided
in Figure 27, which illustrates one of the "straight" wedge-shaped
microelements 102 as it
makes a slit or cut in the skin. The skin is depicted at 300, and it can be
seen that the
sharp edge 116 made up by the two converging faces 110 essentially plows
through the
top portions of the stratum corneum, starting at the point 302, and thereby
parting the skin
along the lines at 306. This leaves an inner portion of the skin temporarily
exposed at
304.
On Figure 27, the microelement 102 is being moved substantially in the
direction
of the arrows "C," thereby indicating that the skin is being cut in that
direction. Of
course, when the microelement 102 is moved in the opposite direction, it will
tend to cut
the skin in the opposite direction and form a new slit, or enlarge an existing
slit.
It will be understood that various depths of the microelements and widths of
the
microelements can be constructed to increase or decrease the size and
penetration depth
of the slits made in the skin, and such dimension variations are envisioned by
the
inventors. Certainly, the exact shapes and sizes can be varied without
departing from the
principles of the present invention.
Figure 11 shows a similar wedge-shaped microstructure array at 120, which has
individual wedge-shaped microelements 122 that have two separate through-holes
at 126.
The microelements 122 are all mounted on a base or substrate 124. As viewed in
Figure
11, the columns of microelements 122 are somewhat different from one another,
in that
they are offset from one another in adjacent rows. This need not be the case,
and
alternatively the columns could be identical to one another to eliminate any
offset, if
desired. Again, alternatively there could be several columns with various
offsets before
the microelement pattern repeats, or the offsets could be substantially random
so that
there is no repetitive pattern.
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Figure 12 shows further details of the individual microelement 122, in which a
top
surface 134 and elongated side walls 132 are exhibited, along with converging
side walls
130 that come to a sharp edge 136. A base line 138 is also illustrated as'the
junction
between the microelement 122 and the substrate 124. The through-holes 126 are
created
to penetrate entirely through the microelement 122, and preferably will also
penetrate
entirely through the base 124, although the holes 126 can become passageways
that do
not entirely penetrate through the base or substrate, but instead connect to
some type of
perpendicular runs or passageways, if desired. Since there are two separate
holes 126 per
microelement 122, it is possible to simultaneously deliver two different
actives (one per
hole in a single microelement) in a single operation, if desired.
The microelements 122 are designed to perform both a skin penetration function
and a delivery procedure in a single step. In this particular structure, it
can almost be
guaranteed that there will be a lack of build-up of dead skin and other
foreign matter
within the delivery holes or passageways 126. Even if some of this foreign
matter or
dead skin cells accumulates in these passageways 126, a capillary action may
result and
accomplish delivery of at least one active or drug through the passageways 126
and into
at least, the epidermal layer of the skin.
Figure 13 illustrates a microstructure array designated by the reference
numeral
140 that contains a large number of individual wedge-shaped microelements 142
that are
mounted to a base or substrate 144. These wedge-shaped microelements 142
contain a
through-slot 146, through which at least one active or drug can be delivered
through the
outer skin surface just after the stratum corneum has been penetrated. In a
similar manner
to the structures of Figure 11, the microelement array or patch 140 will
preferably be
placed on the skin surface and rubbed in a back and forth manner substantially
along the
direction "C" (which is a preferred, predetermined direction) to penetrate or
cut skin cells
of the stratum corneum.
Figure 14 shows greater details of an individual microelement 142, showing a
top
surface 154, side walls 152, converging side walls 150 that come to a
relatively sharp
edge 156, and a base line 158 where the microelement 142 adjoins the base or
substrate
144.
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The through-slot 146 can provide a larger cross-sectional area for delivery of
at
least one active or drug to the skin surface, as compared to the microelement
122 of
Figure 12. Of course, the actual dimensions of the microelement 142 could be
either
larger or smaller than similar microelements 122 illustrated on Figure 12.
Both sets of
microelements 122 and 142 are relatively simple to construct, although the
ones with the
through-slot 146 may be somewhat easier to construct as compared to
constructing
multiple smaller through-holes 126.
The patch or array 140 can be used for a combinational step of skin
penetration
and delivery of at least one active, in a similar fashion to that described in
some of the
earlier embodiments. Other similar shapes of wedge-shaped structures could
easily be
constructed without departing from the principles of the present invention.
Figure 15 discloses an array or patch 160 of triangular-shaped wedge
microelements 162, mounted on a base or substrate 164. As seen in Figure 16,
each of
the microelements 162 consists of an elongated triangular shape, having a pair
of
triangular side walls 170, a pair of sloped elongated side walls 172, a top
edge 174, and a
pair of base lines 178. The junction between the triangular end walls 170 and
the
rectangular but sloped side walls 172 is designated at the reference numeral
176. The
peak of the triangle is illustrated at 174, which is only one point along the
top edge 174 of
the microelement 162.
These triangular-shaped wedges can be useful in a skin penetration procedure,
and
preferably will be placed on skin in the form of a patch and then rubbed back
and forth
over the skin substantially in the direction "C" (which is a preferred,
predetermined
direction). The individual columns of microelements can be offset from one
another in
adjacent columns, as seen in Figure 15. Alternatively, the columns could be
identical to
one another, without any offset. Another alternative could arrange several
columns with
various offsets before the microelement pattern repeats, or the offsets could
be
substantially random so that there is no repetitive pattern.
Figure 17 discloses a similar microelement array 180, which has triangular-
shaped
wedges as individual microelements 182 that are placed or are formed upon a
base or
substrate 184. In the "patch" 180, there are multiple through-holes 186 and
channels 188
for placing at least one active through the stratum corneum.
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Figure 18 shows the channels 188 and holes 186 in a magnified view, in which
the
holes 186 would typically be designed to penetrate entirely through the
substrate 184;
however, such holes 186 could only partially penetrate the base if they
connect to some
other type of passageway within the base structure itself.
The triangular shape of the microelement 182 is seen on Figure 18 along the
side
wall 190, which connects to sloped, rectangular side walls 192 along edges
196. A top
edge 194 exists between the two triangular side walls 190, and a base line 198
marks the
line between the microelement 182 and the substrate 184.
On Figure 18, there are three separate channels 188 in the surface of the
elongated
side wall 192. Of course, fewer channels could be utilized, if desired, or
even more
numerous channels could be used. These channels 188 lend themselves well for
capillary
action to allow at least one active to flow through the holes 186 and along
the channels
188 into the stratum corneum, even if the areas between the microelements 182
become
substantially full of dead skin cells and other foreign substances.
The triangular wedge structures of both Figures 16 and 18 are basically
designed
to penetrate the stratum comeum layer of skin. This is accomplished by moving
the
microelement patches 160 or 180 in a back and forth manner substantially in
the direction
"C" as shown on Figures 15 and 17. Of course, if the microelement patches were
to be
moved in a different direction, particularly one that was perpendicular to the
line "C"
(which is a preferred, predetermined direction), then it is quite likely that
the skin would
not be cut and penetrated (at least not to the extent as compared to when the
patch is used
in the intended "C" direction). This has much usefulness, however, that
concept is not
part of the present invention. Instead, that type of methodology is disclosed
in a
companion patent application, filed on September 14, 2001 under Serial Number
09/952,403, which is also assigned to The Procter & Gamble Company, and having
the
title "Microstructures for Treating and Conditioning Skin."
Another refinement of the triangular-shaped wedge is illustrated on Figures 19
and 20. On Figure 19, a microstructure array or patch 200 is illustrated as
containing
multiple wedge-shaped microelements 202 that are placed upon, or are formed
thereon, a
base or substrate 204. As seen in Figure 20, each of the microelements 202 is
comprised
of three separate triangular-shaped wedges, each having a space therebetween
at 206.
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On Figure 20, it can be seen that the three sections of the triangular-shaped
wedge
202 includes a triangular-shaped side wall 210, a pair of rectangular, sloped
side walls
212, a top edge 214, and a base line at 216 where the microelement 202 joins
the
substrate 204. Each of the three wedge shapes is separated by a space 206, in
which a
center triangular wedge shape is surrounded on both sides by a second, outer
similar
wedge shape, and spaced apart from each of these outer wedge shapes by the
spacing area
206.
The three separate wedge shape of microelement 202 (which are separated by the
spaces 206) provide more individual cutting edges 214. Each peak of a
triangular end
wall 210 represents a new cutting or "plowing" point when the patch 200 is
moved
substantially along the line "C".
The preferred use of the array or patch 200 is to apply the patch directly to
the
skin, and then rub the patch in a back and forth manner along the skin surface
substantially in the direction "C" as seen on Figure 19 (which is a preferred,
predetemlined direction). This particular design penetrates the skin outer
layers quite
well, but is not designed to also apply an active at the same time. Of course,
through-
holes and channels could be added to this structure, if desired, although that
type of
structure would probably be easier to construct when using the shape disclosed
in Figure
18 for the microelement 182.
It will be understood that a microelement patch could be composed of any one
shape of microelements, or could be comprised of several different shapes on a
single
substrate or patch structure, without departing from the principles of the
present
invention. Moreover, it will be understood that the microelements disclosed
herein could
be of all the same height, or of different heights on the same substrate or
patch, without
departing from the principles of the present invention. Finally, it will be
understood that
minor modifications to the shapes disclosed in the drawings are contemplated
by the
inventors, and would still fall within the principles of the present
invention.
It will also be understood that the microelement arrays or patches that
contain
through-holes or through-slots need not have such through-holes or through-
slots for each
and every one of the individual microelements that make up the array. In other
words, the
passageways that flow through the microelements (or adjacent thereto) could be
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constructed on only one-half of the microelements, if desired, while still
achieving most
of the results that would otherwise be achieved if such through-holes or
through-slots
were found at each of the microelements. Certainly, the holes or slots could
be varied in
size or diameter to either reduce or increase the amount of fluidic material
that flows
therethrough. All of these variations are contemplated by the inventors, and
would fall
within the principles of the present invention.
In general, the microelements of the present invention described above are
longer
than those used only for exfoliation, and the lengths of the microelements
would typically
be in the range of 50-1000 microns. This will allow the microelements to
penetrate the
stratum corneum. As noted above, on Figures 1, 3, and 21, the direction of
sliding the
patch is not important; however, on Figures 5, 7, 9, 11, 13, 15, 17, and 19,
the direction of
sliding is more important, and should be substantially in the direction as
depicted by the
arrow "C." This will allow the microelements to cut the skin, and to penetrate
the skin to
a depth that will pierce the stratum corneum to a certain extent. This will
allow an active
or other type of fluidic material or fluidic compound (such as a liquid or a
cream) to
penetrate much more easily through the stratum corneum.
Figure 21 illustrates a "coiled appendage" of a sort, in which multiple curved
wedge-shaped microelements at 222 are placed on a substrate 224 to form an
array or
patch generally designated by the reference numeral 220. Figure 22 illustrates
one of
these arcuate microelements 222 in greater detail. The microelement 222
includes two
wedge-shaped points that are made up of relatively flat surfaces 230 that
converge at an
edge 236. The two wedge-shaped "cutting surfaces" at the edges 236 are joined
by a
curved body that has side walls 232, a top surface 234, and a base "line" at
238 that is
curved or arcuate in shape.
The array or patch 220 is used by placing the patch on the surface of skin,
and
then rotating the patch substantially along the arc designated at the letter
"C." This will
tend to slit or otherwise cut the skin along the relatively sharp edges 236 in
either
direction of the curved microelements 222.
The curved microelements 222 on the array/patch 220 can be used in two
methodologies: (1) the skin is first cut, the patch 220 removed, and then a
fluidic
compound (e.g., a liquid material or cream) is applied to the skin; (2) the
fluidic
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compound is applied first to the skin, then the array/patch 220 is pressed
down on the
same area of the skin and rotated to create the openings, thereby allowing the
fluidic
compound to penetrate more easily through the stratum corneum.
A similar arcuate or curved wedge structure is illustrated in Figure 23, in
which
the individual microelements at 242 are placed upon a substrate 244 to make up
an array
or patch 240. These curved wedges also may be referred to as "coiled"
structures. One of
the microelements 242 is illustrated in greater detail in Figure 24, and it
can be seen that
through-holes 246 are placed through the top surface 254 of the microelement
242. This
will allow a fluidic compound to pass through the holes 246 and into the skin
after the
stratum corneum has been slit or otherwise pierced by the arcuate
microelements 242.
Each curved microelement 242 exhibits a pair of sharp edges at 256 that are
made up by
relatively flat sides 250 that converge along the line 256. The curved
structure has side
walls 252, a top surface 254, and a base "line" or arc at 258 wliere the
microelement 242
joins the substrate 244.
In the structures of Figures 23 and 24, the patch 240 would typically be
placed
upon the skin surface and then rotated substantially in the direction
designated by the
curve "C." The fluidic compound that is to penetrate through the stratum
corneum is
already contained within some type of reservoir or chamber (or perhaps a non-
woven
impregnated material) that will then seep through the holes 246, including by
capillary
action.
An alternative structure is illustrated in Figure 25, in which the curved
microelements 262 exhibit through-slots at 266 that are also arcuate in shape.
The curved
microelements 262 are placed upon a substrate 264, and the overall structure
makes up an
array or patch 260. Figure 26 shows the individual microelement 262 in greater
detail,
and illustrates the sharp edges at two of the ends of the curved microelement
at 276,
which are made up of converging side walls 270. A curved side wall 272 is
illustrated,
along with a top surface 274 and a base "line" or arc at 278 where the
microelement 262
joins the substrate 264. The through-slot 266 is easily visible in Figure 26.
The arcuate microelement 262 is used in a similar manner to that illustrated
in
Figure 24, in which the array/patch 260 is placed upon skin and rotated
substantially
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along the arc "C," and then a fluidic compound is allowed to pass through the
slot 266
tlirough the stratum corneum, as desired.
Figure 28 illustrates the wedge-shaped microelement 102 from its "sharp" end
in
an elevational view. The two converging sides 110 are seen to form a
relatively sharp
edge at 116, which travels vertically from the top of the substrate/base 104
to the top
surface 114 of the microelement 102. The angle "A" between the substrate top
surface at
104 and the side wall 112 is clearly visible. On Figure 28, this angle "A" is
approximately 90 , and therefore forms a perpendicular angle.
Figure 29 shows an alternative shape for a wedge-shaped microelement
designated by the reference numeral 402. This wedge-shaped microelement has a
similar
appearance from above to that of the wedge-shaped microelement 102, except
that its
elongated side walls are not formed by a perpendicular angle to the substrate.
On Figure 29, the substrate 404 is joined to the outer wall that is elongated
along
the side of the microelement (i.e., the wall 412) by an angle "A" that is
greater than 90 .
Its complimentary angle is illustrated at "B." Angle B is between 45 and 60
in Figure
29, but of course could be any angle that will successfully operate to
penetrate the skin.
The front walls that converge are illustrated at 410, and converge along the
relatively sharp edge at 416. This non-perpendicular wall shape of a
microelement 402
may have some advantages with regard to manufacturing and with regard to
overall
strength of the structure.
Figure 30 is a side elevational view in partial cross-section of a
microstructure that
contains an array of different shaped microelements and a corresponding
substrate,
designated at the reference numeral 460, as well as an underlying reservoir
structure
designated by the reference numeral 470. On Figure 30, the array of
microelements 460
is illustrated as having a set of pyramidal microelements 32 having grooves or
channels
38 along the sides of the pyramid shapes, and a set of wedge-shaped
microelements 122
having through-holes 126. The base or substrate is designated at the reference
numeral
462.
On Figure 30, the through-holes actually travel all the way through both the
microelements and the substrate 462 to form passageways, and these passageways
are
depicted in two groups. The first group is a combination of the grooves or
channels 38 in
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the pyramidal microelements 32 that are connected to the through-holes 464, to
form a
common set of passageways that extend from the bottom surface of the base or
substrate
462 through the top surface of this substrate 462 and are in communication
with the
channels or grooves 38. The second set of passageways comprises a set of
through-holes
466 that are in communication with the microelement through-holes 126 of the
wedge-
shaped microelements 122. These through-holes 126 and 466 must be in
registration with
one another to form complete passageways from the top of the microelement 122
to the
bottom of the substrate of 462. Naturally, there could be some horizontal runs
that
connect similar passageways, if desired.
The bottom portion 470 depicted in Figure 30 includes a reservoir structure
that
has a bottom wall at 472 and a reservoir area or volume at 476 that is bounded
by the side
walls of the reservoir at 474. Multiple such compartments or chambers can be
constructed to house multiple actives. The upper portion of this reservoir
structure 470
would typically be planar, as depicted at the reference numeral 478, and would
make
contact against the bottom surface at 468 of the microstructure/substrate
apparatus at 460.
It is important that the reservoir 476 be in communication hydraulically or
pneumatically
with the passageways 464 and 466, thereby allowing a fluidic drug or other
active to
reside within the reservoir confines at 476 until used, and then for the
fluidic drug or
active to be directed through the passageways 464 and 466 to the upper surface
of the
microelements 32 and 122.
Figure 31 illustrates an array of wedge-shaped microelements 102 on a
substrate
104 that makes up a microstructure apparatus designated by the reference
numeral 100.
Microstructure apparatus 100 comprises a top layer that is laminated to a non-
woven
backing 502, which is preferably thin enough so as to be substantially
flexible. This
overall structure is generally designated by the reference numera1500 on
Figure 31.
The top layer 100 that contains the multiple microelements 102 can have as a
substrate and microelement material some type of moldable plastic, such as
nylon, or a
polycarbide material, or PMMA, for example (and these materials may be used
with any
microelement shape). The bottom or backing material 502 preferably is a
substantially
flexible material that exhibits a soft texture. Typically a non-woven material
gives an
impression of cloth, and thus can provide the desired soft texture.
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The non-woven backing material 502 can be laminated with the microelement
layer 100 by use of a chemical glue or a heat-activated adhesive, for example.
On Figure
31, the non-woven backing is somewhat larger in length and width than the
microelement
layer 100, and thus can be seen along the edges.
Figure 32 illustrates a similar laminated structure, however, the
microelements
102 are formed as strips 512, in which there are several such strips that
contain rows of
the microelements. The non-woven backing material can be seen both along the
top and
bottom edges, and also between the strips at 514 on Figure 32. The overall
structure is
generally designated by the reference numeral 510.
In Figure 33, the microelements 102 are visible at the top, as residing above
the
substrate 104. The bottoni portion of the substrate is permanently affixed to
the non-
woven backing material 502, thus leading to the overall structure at 500.
As discussed above, the fixing of the non-woven backing material 502 to the
substrate 104 can be by some type of adhesive used in lamination, or perhaps
using a
sonic bonding process. Alternatively, a co-extruded material could be used.
One major advantage to using a non-woven backing material as depicted in
Figures 31-33 is that this non-woven material 502 (or 514 on Figure 32) can be
impregnated with at least one active, and thereby effectively become a
"reservoir" without
creating an actual chamber having an open volumetric space. This not only
saves a
manufacturing procedure step by not requiring a true open chamber to be
constructed, but
also allows the overall structure of the "patch" shown in the earlier figures
to be made of a.
substantially flexible material that is inuch less likely to exhibit breakage
problems.
It will be understood that various shapes of microelements can be used with
the
non-woven backing material, and various shapes of substrates can be laminated
or
otherwise affixed to the non-woven backing material. It will also be
understood that the
backing material may or may not be impregnated, all without departing from the
principles of the present invention. Finally, it will also be understood that
other suitable
materials besides non-woven materials could be used for the backing at 502 and
514 on
Figures 31 and 32, all without departing from the principles of the present
invention.
Figure 34 illustrates a completely different approach in microstructures for
penetrating skin as compared to the above-described microstructures. A
rotatable
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structure, generally designated by the reference numeral 600, is covered with
a plurality
of microelements 602 that protrude or extend from a cylindrical substrate 604
(i.e.,
affixed on a curved substrate). As illustrated on Figure 35, each of the
microelements
602 has a wedge-shaped pair of edges at 616, which are formed by side walls
610 that
meet at the edge 616. The side walls 610 are separated from the two
longitudinal distal
ends or edges (at 616) by another side wall 612 which appears on both sides of
the
microelement 602. The side walls 612 and end walls 610 are bounded by an upper
surface 614, which includes a through-slot generally designated by the
reference numeral
606. A fluidic material that is stored inside the cylindrical-shaped rotatable
structure 600
can flow out through the slot 606, thereby having the capability of being
dispensed into
skin.
The microelements 602 are very similar in shape to those described on Figures
13
and 14 above, at the reference numeral 142. The microelements 602 are designed
to
penetrate into the skin and through the stratum corneum, thereby enabling the
fluid
material being dispensed through the slot 606 to penetrate into the skin.
A quite unique structure is thereby disclosed, in which the rotatable
structure 600
has an axle member at 608, which can be attached to some type of roller-
structure,
thereby enabling the cylindrical shape of the rotatable structure 600 to
rotate in both
directions indicated by the arrow "C." Ideally, the cylindrical structure 600
will be placed
upon skin and then translationally moved such that the cylinder rotates while
moving
along the surface of the skin, thereby enabling the individual microelements
602 to cut
into the skin and penetrate the stratum comeum while the structure 600 is
being rotated.
A variation of the rotatable structure 600 is illustrated on Figure 36, in
which
microelements generally designated by the reference numeral 622 have a
different shape
than those microelements 602 found on Figures 34 and 35. The overall rotatable
structure
is generally designated by the reference numeral 620 on Figure 36, and
exhibits a
cylindrical shape that is made up of a substrate 624 that has a plurality of
individual
microeleinents 622 protruding or extending therefrom. As the rotatable
structure 620 is
rotated and pressed against skin, the sharp edges of the microelements 622
will penetrate
the skin, preferably through the stratum comeum, as the cylindrical structure
620 is
rotated in either direction indicated by the arrow "C."
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An enlarged view of a single one of the microelements 622 is provided on
Figure
37, in which side walls 630 come together at substantially sharp edges 636.
These sharp
edges are such that they can penetrate the stratum comeum of skin when pressed
down
against the skin while the cylindrical structure 620 is rotated. The top edges
of the side
walls 630 are bounded by a top surface 634.
Both Figures 36 and 37 illustrate a plurality of openings or through-holes
626,
which are placed around the microelements 622. If a fluidic material (e.g.,
drug) is
disposed within the cylindrical structure 620, then that fluidic material can
pass through
the openings 626 and onto the skin as the structure 620 is rotated in the
direction C.
If the rotatable structure 600 or rotatable structure 620 is rotated quickly,
then due
to centrifugal force, the fluidic material will be forced through the openings
(either the
through-slots 606 or the through-holes 626). However, a more positive pressure
can be
created by other structures, which will be discussed below. These alternative
pressure
sources also can be activated by the rolling motion.
It will be understood that the microelements and substrate combination can be
formed as a sheet that is sufficiently flexible to be wrapped around in the
shape of a
cylinder. In such a circumstance, the sheet structure could be formed from an
embossing
procedure, or perhaps from a molding procedure. If the embossing procedure is
utilized
as the fabrication methodology, then a continuous embossing operation would
likely be
chosen by a manufacturer. As an alternative, the cylindrical shape could be
formed
directly by a molding process.
It will also be understood that the actual placement of the microelements on
the
outer surface of the cylinder can be essentially of any pattern chosen by a
designer, in
which the microelements could be formed in straight lines, or in a staggered
configuration, or perhaps in a more random-like pattern. Essentially any set
of distances
between microelements and patterns in their layout on the cylindrical surface
are
contemplated by the inventors, and would not depart from the principles of the
present
invention.
Figure 38 illustrates another alternative embodiment of a cylindrical-shaped
rotatable structure that contains a plurality of microelements thereon. The
overall
cylindrical structure is generally designated by the reference numeral 640,
which contains
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a plurality of microelements 642 that are placed upon or protrude from a
substrate 644. A
plurality of openings or through-holes are indicated at 646, which would allow
a fluidic
material stored within the rotatable structure 640 to pass therethrough and
onto the
surface of skin. The microelements 642 are shaped to penetrate skin at least
through the
stratum corneum layer, thereby allowing the fluidic material to penetrate into
the skin as
the cylindrical structure 640 is rolled upon the skin surface.
In Figure 38, the individual microelements are not symmetrical in shape, as
opposed to those microelements 602 and 622 that were disclosed in Figures 34-
37. As
can be seen in Figure 39, the microelement 642 is shaped like a right triangle
in this side
view, which exhibits a side wal1650 that comes to a point at a distal end 656.
When the
cylindrical structure 640 is rotated in the direction of the arrow "C," it can
be seen in
Figure 39 that the side of the triangle with the distal point at 656 will much
more readily
penetrate into the skin, which is designated at the reference numeral 658. Of
course, if
the hypotenuse 652 (see Figure 40) of the triangle-shaped microelement 642 was
sharp
enough between the side walls 650, then these microelements may also penetrate
the skin
while being rolled in the opposite direction from the arrow C; however, that
is not the
main intent of this embodiment.
Alternative microelement shapes are disclosed in Figures 40-42 that can be
used
with the cylindrical structure 640. On Figure 40, the microelement 642 is
illustrated as
exhibiting two side walls 650 which have a common edge therebetween at 652. A
triangular end wall is formed at 654, which can also be seen on Figure 38. The
peak of
this triangular end wall 654 is at the distal end or point mentioned above, at
reference
numeral 656. It is this point that is to make the main penetration into the
skin.
In Figure 40, a side view D-D of the microelement 642 is depicted as having a
right angle which is bounded by a horizontal line on this figure, and a
vertical line which
is designated by the reference numeral 654. Reference numeral 654 in actuality
is the
triangular end wall that was described above. The side wa11650 is illustrated
as having a
peak point at 656, which runs down a hypotenuse 652. The right angle between
the
horizontal line and the vertical end wall 654 form an angle referred to as "Z"
on Figure
40.
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There are two elevational views on Figure 40; the first view is designated A-A
which illustrates the end wall 654 as being triangular in shape, having two
side walls 650
which come to a point at the distal end or peak at 656. It will be understood
that the
triangular shape in view A-A can be an equilateral triangle, or it could be an
isosceles
triangle which would have two equal sides made up by the line segments 650 on
view A-
A. Of course, a non-isosceles could be provided if desired. The other
elevation view is
B-B, which is from the opposite end of the microelement 642. View B-B shows
the side
walls 650 which are joined at a relatively sharp edge 652, which all intersect
at the top
peak or point at 656.
Figure 41 illustrates an alternative embodiment for a microelement to replace
or
be used in conjunction with the microelements 642 that appear on Figures 38-
40. The
alternative microelement of Figure 41 is generally designated by the reference
numeral
668. As can be seen on Figure 41, microelement 668 has a different angle Z
that can be
viewed from a side view E-E, which shows the side wall 660 as having a
triangular shape,
although the angle Z is an obtuse angle rather than a right angle. The end
wall of
microelement 668 is designated at the reference numeral 664, which would still
have
triangular shape and come to a top point or peak at a distal end or point 666.
The
hypotenuse of the triangle seen from the side view E-E is designated at the
reference
numeral 662. In the other view of Figure 41, both side walls 660 are seen as
meeting at
an edge 662 (which is the hypotenuse of the triangle seen in the other view).
It can be
seen that the top or distal point 666 will form the primary cutting surface
when the
microelement 668 is moved in the direction C by rotation of the cylindrical
structure,
similar to that viewed in Figure 38.
Figure 42 is another alternative embodiment of the microelement 642, in which
the alternative microelement, generally designated by the reference numeral
678, exhibits
an acute angle at Z, as seen in the side view G-G showing the side wall 670.
In this view
G-G, the acute angle Z is bounded by a horizontal line and an end wall 674,
which comes
to a top point or peak at a distal end or point 676. The hypotenuse of this
triangular shape
is at the reference numeral 672.
An end view F-F is also provided on Figure 42, in which the end wall 674 is
illustrated as having a triangular shape, made by the side walls 670, which
meet at the top
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peak or point 676. It will be understood that the triangular shape of the end
wall 674 can
be equilateral, isosceles, or non-symmetric overall, as desired by the
microstructure
designer.
The top view of Figure 42 illustrates the microelement 678 as having two side
walls 670, an end wall 674, all of which meet at the top point or peak 676.
The two side
walls 670 meet along an edge line at 672, which forms the hypotenuse in the
view G-G.
As can be seen in Figure 42, the shape of the microelement 678 will allow its
end wall
surface 674 in conjunction with the top peak or point 676 to readily penetrate
skin when
the microelement 678 is moved in the direction C, typically by rotation of a
cylindrical
structure similar to that of 640 in Figure 38.
The next few figures starting with Figure 43 illustrate various alternative
embodiments for use with the rotatable structure 600 that contains a large
plurality of
microelements 602. It will be understood that any appropriately-shaped
microelement
could be used for virtually any of these alternative embodiments without
departing from
the principles of the present invention. Keeping in mind that the main purpose
is to
penetrate skin, all of the microstructures disclosed in the next few figures
can penetrate
the stratum comeum and deliver a drug or other fluidic compound through the
stratum
corneum and into the skin.
Referring now to Figure 43, a hand-held roller-structure generally designated
by
the reference numeral 700 is depicted, which has a chassis or body 702, three
axles at
608, and three cylindrical structures 600 that contain the microelements. When
this
roller-structure 700 is pressed against skin 704, and moved in either
direction of arrows
"C," then the microelements will penetrate through the top layers of the skin
(i.e., at least
through the stratum corneum), thereby allowing delivery of a drug or other
fluid
compound into the skin. It will be understood that this embodiment 700 could
alternatively comprise a single cylindrical roller 600, or a much larger
number of such
rollers, as desired by the designer of the microstructure system. Moreover, if
multiple
cylindrical structures are used in the overall device 700, then the pattern of
microelements
for the different rollers could be the same, or could be different if desired.
The use of the
word "pattern" implies either the same shaped microelements in different
configurations
as to their positions on the substrates of one of the cylindrical rollers, or
different shaped
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microelements on different rollers, in which a first microelement shape is
found on a first
roller 600 and a second microelement shape is found on a second roller 600, or
some
combination of shapes on a single roller.
Referring now to Figure 44, a single roller 600 is illustrated, in which this
single
roller is a rotatable structure that contains a large number of microelements.
The roller
600 is attached to an arm 714, that is further attached to an extending member
712 that
can be held by a person's hand. The overall structure is generally designated
by the
reference numeral 710, which contains the member 712, the arm 714, and the
cylindrical
rotatable roller-structure 600. When this structure 710 is held such that the
cylindrical
rotatable roller-structure 600 is placed upon skin 718 and then moved in
either direction
designated by the arrows "C," then the individual microelements will penetrate
the skin
(preferably through the stratum corneum layer) so as to allow delivery of a
drug or other
fluidic compound into the skin. As noted above in reference to Figure 43, the
microelements on the roller 600 can be of the same type (i.e., size and shape)
and can be
laid out in a symmetrical pattern such as straight lines, or alternatively can
have a
staggered configuration, or with anotlier alternative in mind, the
microelements can be of
different sizes and shapes, if as desired by the designer of the
microstructure. Another
alternative embodiment is illustrated in Figure 45, in which an overall hand-
held roller-
structure generally designated by the reference numeral 720 provides a
cylindrical roller,
which is designated by the reference numeral 601. A main body or chassis 722
is
contacted by a person's hand, and this body 722 contains a reservoir at 724
which
contains a fluidic compoiind 726. The fluidic compound 726 is dispensed by the
person
pressing down on a top button 728, which produces pressure inside the
reservoir (or
chamber) 724. When this occurs, the fluid 726 will be dispensed through a
pathway to an
outlet port 728 that is in proximity to the surface of the skin at 730.
The cylindrical surface of roller 600 can be made disposable for one-time use
applications. It will be understood that the microstructure cylindrical
surface can be made
disposable for all of the embodiments disclosed in this patent document,
including the
"chassis" embodiments such as illustrated in Figure 43.
It will also be understood that there is some benefit in destroying the
functionality
of the microelements after they have been used, particularly for one-time
usage
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applications (i.e., with disposable rollers or disposable sliding meinbers,
etc.). The
destruction process can be achieved using a built-in device if desired, or it
can be
achieved using an independent, separate microelement destructive apparatus,
that crushes
or melts the sharp edges, for example.
The body or chassis 722 also contains an axle 608 that holds the roller 601 in
place. When the overall roller-structure 720 is moved in the direction of the
arrow "C,"
then the fluid that is dispensed through the outlet port 728 forms a thin
layer on top of the
skin surface, as seen at 732 on Figure 45. The rotatable roller 601 will pass
over this
layer of fluid 732 and, as the microelements cut into the skin through the
stratum corneum
layer, the fluid layer 732 will be forced down and through these openings in
the skin to
become a "layer" of fluid beneath the top layer of the skin, at 734 on Figure
45. As in the
other embodiments disclosed in this patent document, the exact size and shape
of the
microelements on the rotatable roller 601 can be of many different sizes and
shapes,
while serving the purposes of cutting through the stratum corneum layer and
allowing the
fluid to be passed through the stratum corneum and into the skin, all without
departing
from the principles of the present invention.
In this roller-structure embodiment 720, the microelements formed on the
cylindrical surface of the roller 601 would typically have no openings, and
would
comprise microelements that form protrusions only. It will be understood that
the
pressure at the outlet port 728 can be controlled by the aperture size and/or
the shape of
the fluid pathway, thereby controlling the rate of fluid dispensing.
Another alternative embodiment of the present invention is illustrated in
Figure
46, in which an overall roller-structure 740 comprises a main body or chassis
742, which
contains a different type of fluid chamber therewithin, and also comprises
another
microelement cylindrical roller. As the main body 742 is held by a person's
hand, the
entire roller-structure 740 can be pushed in the direction of the arrow "C,"
which will
cause the cylindrical rotatable roller 601 to rotate about an axle 608. This
rotation causes
a worm gear 760 to turn, through a gear box 603 that can be used to control
the ratio of
turning between the worm gear 760 and the cylindrical roller 601.
Worm gear 760 interacts with a lead screw 762, which interacts with a
traveling
nut 764 that is located within a reservoir or chamber 744. When the worm gear
760 and
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lead screw 762 turn in the correct direction, the traveling nut 764 will move
toward the
right as seen on Figure 46, thereby squeezing a fluidic material 746 out of
the reservoir,
and through an outlet fluid path to an outlet port 748, which is in close
proximity to the
top surface of skin 750.
It will be understood that a small one-way clutch could be included within the
gear box 603 to prevent the traveling nut 764 from moving along its
translational axis if
the roller-structure 740 is moved in the direction opposite that shown by the
arrow C.
This is an option, and would not be entirely necessary if cost considerations
were of
paramount importance.
When the fluid is dispensed through the outlet port 748, it forms a thin layer
at
752 on top of the skin surface 750. When the cylindrical roller 601 comes
along and
presses against the skin and this fluid layer 752, it both cuts through the
stratum corneum
layer and forces the fluidic material in layer 752 through the newly formed
openings in
the stratum corneum, thereby placing the fluid beneath the skin and forming a
"layer" as
seen at 754 on Figure 46.
It will be understood that the microelements formed on the surface of the
cylindrical roller 601 would typically not have through-holes or other types
of openings,
and instead would comprise protrusions only, since no fluid need be dispensed
from the
inner workings of the cylindrical roller 601. Furthermore, the microelements
formed on
the cylindrical surface of roller 601 can be of virtually any size and/or
shape or pattern, as
desired by the designer, to meet a specific application, without departing
from the
principles of the present invention.
Another alternative embodiment is illustrated on Figure 47, in which a fluidic
chamber or reservoir is depicted as being separated by a traveling nut 764, in
which fluid
material to the right of the traveling nut 764 (in this view) would be located
within the
volume 746, and the remaining portion of the chamber would be located to the
left of the
traveling nut, in the volume 744. The traveling nut 764 can be moved by
rotation of a
lead screw 762, which when rotated in the direction depicted by the arrow "R,"
would
cause the traveling nut to move toward the right, and any fluid within the
chamber 746
would be dispensed through an outlet port and further into another volume or
space that
provides fluid through multiple openings at 749. This structure could be
utilized in the
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moveable apparatus illustrated in Figure 46, and the multiple outlet ports 749
would allow
for a relatively wide swath of fluidic compound to be dispensed upon the
surface of skin.
Bearing that in mind, a cylindrical roller-structure containing microelements
for cutting
through the stratum corneum layer would likely be disposed such that the
longitudinal
axis of the roller-structure would be parallel to the longitudinal axis of the
lead screw 762.
The next three figures, Figures 48-50, illustrate yet further alternative
embodiments in which a cylindrical and rotatable apparatus is utilized to
dispense a
fluidic compound through multiple openings in multiple microstructures.
Referring now
to Figure 48, a cylindrical rotatable apparatus 770 is illustrated, which
includes an axle
608, a cylindrical substrate 604, and a plurality of microelements 602,
similar to the
structure 600 that was first illustrated in Figure 34. The overall apparatus
770 also
includes a dosing paddle 774 that rotates about the longitudinal axis of the
axle 608, when
the cylindrical structure 600 is rotated in the direction of arrow "C." A
fixed paddle 772
is used as the beginning stop and end stop of the moving paddle 774. A ratchet
776 and
paw 778 are used so that the dosing paddle 774 will move only when the
structure 770 is
rotated in the direction C, and not when the structure 770 is rotated in the
opposite
direction.
When the dosing paddle 774 moves in an angular manner, it will tend to squeeze
fluidic material within the overall cylindrical roller 600 and create
pressure, thereby
squeezing the fluidic material out through openings 606 in the microelements
602. It will
be understood that virtually any size or shape microelements could be useful
in this type
of embodiment, as desired by the designer of the microstructure system.
A gear system could be added to the overall structure 770 to prolong the
dosing if
that is desired. With or without a gear system, the overall structure 770
could be
manufactured such that the dosing paddle 774 makes a complete revolution from
its
beginning stop to its end stop position rather quickly, upon rotation of the
structure in the
direction of arrow C.
In Figures 49 and 50, another alternative embodiment for a dispensing
structure,
generally designated by the reference numeral 780, is illustrated. The
assembly 780
comprises an outer drum 781, an inner drum 782, a wiper or rotatable paddle
783, a
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planetary plate 784, a planetary gear 785, and at least one support 786. The
support 786
(or pair of supports) cooperates with a handle that is not illustrated on
these figures.
The outer drum 782 incorporates a plurality of microelements 787 which contain
dispensing openings or through-holes 788. A central shaft 789 provides bearing
support
for the ends of the outer drum 781, and the shaft 789 is in turn supported by
the support
786 (or a pair of supports). A bearing aperture 761 of the outer drum 781
extends
inwardly through a boss 763, which in turn incorporates gear teeth 765 about
its outer
diameter.
The central shaft 789 also provides bearing support for the imier drum 782.
Inner
drum 782 includes an inner drum flange 767 which has an inner diameter surface
that is
provided with gear teeth 769 which have the same size and pitch as the gear
teeth 765.
The shaft 789 provides bearing support for the planetary plate 784 between the
boss 763
and the outer drum 781, and the closed end of inner drum 782.
The planetary gear 785 incorporates a spindle 751 that is rotatably and
slideably
mounted within a slot 753 in the planetary plate 784. Slot 753 is so
constructed that one
end is further from the outer diameter of the planetary plate 784 than its
other end. As the
planetary gear 785 is driven up the slot 753, it is placed into operating
cooperation with
the gear teeth 765 and 769. If the assembly 780 is rotated in the opposite
direction, the
planetary gear 785 is driven down the slot 753 and out of mechanical
cooperation with
the gear teeth 769. The result of this construction is that the planetary gear
785 will
function as an overrunning clutch, providing one-way rotation to the inner
drum 782.
The inner drum 782 includes an internal dam 755 that moves slowly away from
the wiper 783 which is rigidly affixed to the non-rotating shaft 789. The
inner drum 782
is also provided with slots or holes 757 which protrude therethrough, in which
these slots
or openings are located transversely across the drum 782 on the opposite side
of the dam
755 from the wiper 783. The internal dam 755 extends inwardly to slideably
touch the
shaft 789. In this manner, an inner reservoir at reference numeral 759 is
formed within
the inner drum 782, and this inner reservoir slowly decreases in volume as the
assembly
780 is operated. It should be noted that the rate of decrease of the volume of
inner
reservoir 759 is predetermined by the gear ratios of the planetary gear set,
and also that
the inner drum 782 rotates at a substantially slower rate than the outer drum
781.
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If a fluidic material is placed within the reservoir 759, when the roller unit
780 is
rotated or rolled in the direction C along a surface (such as skin), the
liquid is' slowly
forced out through the slots or openings 757 into an outer reservoir at 741.
The liquid
will then disperse throughout this reservoir 741 to substantially uniformly
supply fluid to
the plurality of dispensing openings or holes 788 with a metered flow of the
fluid.
As the outer drum 781 rotates clockwise (as viewed in Figure 49), the
planetary
gear 785 is driven counterclockwise (in this same view) by virtue of the gear
teeth 765
that are incorporated into the outer diameter of the boss 763. The planetary
gear 785 is
also driven to the "top" of the slot 753, where it is forced into cooperation
with the gear
teeth 769 of the inner drum 782. The inner drum 782 will rotate
counterclockwise (in this
view) at a reduced rate when this occurs.
If the outer drum 781 is rotated in a counterclockwise direction (as viewed in
Figure 49), the planetary gear 785 will be driven in a clockwise direction (in
this view)
which causes it to translate to the "lower" end of the slot 753. When this
occurs, the iimer
drum 782 will become disengaged and will not reverse rotate. Both ends, or
only one
end, of the roller assembly 780 can be provided with one or more planetary
gear sets.
Figures 51 and 52 illustrate another embodiment of a cylindrical-rolling
microstructure that is generally designated by the reference numeral 790. The
rotatable
structure 790 includes as its skin penetrating structure a cylindrical
microstructure 600
that contains a plurality of microelements 622, similar to those disclosed in
Figures 36
and 37. This cylindrical microstructure rotates on an axle 608, and, for
reasons described
below, has a single preferred direction of rotation as illustrated by the
arrow "C."
On the outer ends of the overall apparatus 790 are two sets of skin-engaging
screw
threads 792 and 794. (These threads comprise a "skin engagement area.") As
best seen
in Figure 52, the shape of the individual threads will have an effect on the
skin surface,
and the purpose is to stretch the skin between these outer ends containing the
threads 792
and 794. For example, in the threads 792, the general shape of individual
threads is
indicated at 793. When the apparatus 790 is rolled or rotated in the direction
C, the shape
of the thread 793 will tend to pull the skin to the left as viewed on Figure
52. In a similar
manner, the general shape of the threads 794 is shown as the individual
threads 795,
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which will tend to pull the skin to the right as viewed on Figure 52 when the
apparatus
790 is rolled in the direction C.
The result of employing the sets of threads 792 and 794 on the ends of the
cylindrical apparatus 790 is that the skin will be stretched taut in the area
illustrated at
796 on Figure 52, whereas the skin at the areas 798 on Figure 52 will tend to
be
somewhat bunched up. In this manner, the threads will "catch" the skin
(assuming the
threads are deep enough) and maintain contact witll the skin without allowing
much in the
way of slippage of the skin. This can enhance penetration of the skin by the
microelements by tightening the skin in the direction of dosing using a
fluidic compound,
such as a drug.
It will be understood that various sizes and shapes of the threads used to
tighten
the skin can be utilized with the roller-structure 790, without departing from
the
principles of the present invention. Moreover, it will be understood that the
exact sizes
and shapes of the microelements and their spacings can be greatly varied when
used in
the roller apparatus of Figures 51 and 52, all without departing from the
principles of the
present invention. It should be noted that, while no openings are illustrated
in detail in
Figures 51 and 52, some methodology for dispensing a fluidic compound onto the
skin
and through the stratuin corneum would be included in such a roller apparatus
as
illustrated at 790. Their absence on Figures 51 and 52 are solely for the
purpose of clarity
in these drawings.
Figures 53-58 illustrate alternative shapes of microelements that can be used
in the
microstructures described above. In Figure 53, a pair of pyramidal-shaped
microelements
810 and 830 are illustrated as protruding from a substrate 804, and all of
this is included
as a microstructure, generally designated by the reference numeral 800. The
two
pyramidal halves 810 and 830 can be referred to as comprising a single
microelement,
generally designated by the reference numeral 802. The top view of Figure 54
will
readily show that there is a spaced-apart relationship between the
microelements-halves
810 and 830, and moreover, a slot 806 is formed in this spaced-apart area
'along the
substrate 804. As can be seen in Figure 55, the slot 806 extends entirely
through the
substrate 804, thereby forming a through-slot or opening that can be used to
dispense a
fluidic compound, if desired.
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Microelement-half 810 includes two sloped side walls 812 and 814, which are
joined at a line or edge 816. This edge 816 runs between the substrate 804 and
a top peak
or distal point 818, which also is the intersecting point for an edge 820 that
runs from the
substrate 804 to this point 818, as well as a second edge 822 that runs from a
different
portion of the substrate 804 to the top point 818. The edges 820 and 822 are
the upper
boundaries of a triangular inner face or inner end wa11824.
Microelement-half 830 includes two sloped side walls 832 and 834, which are
joined at a line or edge 836. This edge 836 runs between the substrate 804 and
a top peak
or distal point 838, which also is the intersecting point for an edge 840 that
runs from the
substrate 804 to this point 838, as well as a second edge 842 that runs from a
different
portion of the substrate 804 to the top point 838. The edges 840 and 842 are
the upper
boundaries of a triangular inner face or inner end wall 844. Since the edges
816 and 836
are substantially sharp, the microelement 802 will readily penetrate into the
skin and
through the stratum corneum layer when this microelement is moved in either
direction
"C" as indicated by the arrow on Figure 54.
Figures 56-58 illustrate another alternative embodiment for a microelement
that
comprises two half-structures, similar to that described in reference to
Figures 53-55.
The overall structure is generally designated by the reference numeral 850,
which
includes a substrate 854, a first wedge-shaped microstructure 860, a second
wedge-
shaped microstructure 880, and a through-slot 856. Moreover, the two
microelement-
halves 860 and 880 can be, in combination, referred to as a single
microelement 852.
The microelement-half 860 comprises a wedge-shaped structure that has a
triangular shape when viewed from above (see Figure 57). The side walls of
this
structure 860 are designated at the reference numerals 862 and 864, as well as
an inner or
end wall at 874. The top surface is designated by the reference numera1868.
The two side walls 862 and 864 come together at a substantially sharp edge
866,
which extends from the substrate 854 to the top surface 868. The side wall 862
and the
inner end wall or face 874 come together at an edge 870, which extends from
the
substrate 854 to the top surface 868. The side wall 864 and the inner wall or
face 874
also come together at an edge 872, which extends from the substrate 854 to the
top
surface 868.
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The microelement-half 880 comprises a wedge-shaped structure that has a
triangular shape when viewed from above (see Figure 57). The side walls of
this
structure 880 are designated at the reference numerals 882 and 884, as well as
an inner or
end wall at 894. The top surface is designated by the reference numera1888.
The two side walls 882 and 884 come together at a substantially sharp edge
886,
which extends from the substrate 854 to the top surface 888. The side wall 882
and the
inner end wall or face 894 come together at an edge 890, which extends from
the
substrate 854 to the top surface 888. The side wall 884 and the inner wall or
face 894
also come together at an edge 892, which extends from the substrate 854 to the
top
surface 888.
As can be seen in Figure 58, the opening 856 runs completely through the
substrate 854, thereby forming a through-hole or througll-slot that will allow
a fluidic
material to pass therethrough. Since the edges 866 and 886 are substantially
sharp, the
microelement 852 will readily penetrate into the skin and through the stratum
corneum
layer when this microelement is moved in either direction "C" as indicated by
the arrow
on Figure 57. Of course, the other edges 870, 872, 890, and 892 could also be
made to be
substantially sharp, so that, if desired, the microelement 852 would also
readily penetrate
skin through the stratum corneum layer if the microelement were moved in a
direction
perpendicular to the arrows "C."
The foregoing description of a preferred embodiment of the invention has been
presented for purposes of illustration and description. It is not intended to
be exhaustive
or to limit the invention to the precise forin disclosed. Obvious
modifications or
variations are possible in light of the above teachings. The embodiment was
chosen and
described in order to best illustrate the principles of the invention and its
practical
application to thereby enable one of ordinary skill in the art to best utilize
the invention in
various embodiments and with various modifications as are suited to the
particular use
contemplated. It is intended that the scope of the invention be defined by the
claims
appended hereto.
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