U.S. patent application number 11/356929 was filed with the patent office on 2006-09-07 for method and apparatus for supplying gas to an area.
Invention is credited to Coni F. Rosati.
Application Number | 20060200100 11/356929 |
Document ID | / |
Family ID | 37392852 |
Filed Date | 2006-09-07 |
United States Patent
Application |
20060200100 |
Kind Code |
A1 |
Rosati; Coni F. |
September 7, 2006 |
Method and apparatus for supplying gas to an area
Abstract
Embodiments of the present invention are directed to various
designs and packaging methods for a gas delivery device and
materials for supplying one or more predetermined gases to a target
area as well as to application specific opthamological embodiments.
With regard to the gas delivery device, the device may include a
reservoir, a gas diffusion portion for communicating gas from the
reservoir and one or more predetermined gases at concentrations
greater than atmospheric contained within the reservoir, wherein
the device does not generate gas and may be packaged prior to use
with the one or more predetermined gases.
Inventors: |
Rosati; Coni F.; (Carlsbad,
CA) |
Correspondence
Address: |
MINTZ LEVIN COHN FERRIS GLOVSKY & POPEO
666 THIRD AVENUE
NEW YORK
NY
10017
US
|
Family ID: |
37392852 |
Appl. No.: |
11/356929 |
Filed: |
February 16, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10781965 |
Feb 18, 2004 |
7014630 |
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11356929 |
Feb 16, 2006 |
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60479745 |
Jun 18, 2003 |
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60654037 |
Feb 17, 2005 |
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60662019 |
Mar 14, 2005 |
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60711796 |
Aug 26, 2005 |
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Current U.S.
Class: |
604/304 ; 206/.7;
602/48 |
Current CPC
Class: |
A61F 13/00051 20130101;
B65D 81/2069 20130101; A61F 9/0008 20130101; A61F 13/02 20130101;
A61H 2033/143 20130101; A61M 2202/0208 20130101; A61H 35/00
20130101; A61F 13/0216 20130101; A61F 2013/00174 20130101; A61M
35/30 20190501; A61F 13/0206 20130101; A61M 35/006 20130101; A61F
13/0213 20130101; B65B 25/008 20130101; A61H 33/14 20130101; A61F
2013/0017 20130101; A61F 13/0226 20130101; B65B 31/00 20130101 |
Class at
Publication: |
604/304 ;
602/048; 206/000.7 |
International
Class: |
A61F 13/00 20060101
A61F013/00; B65B 3/00 20060101 B65B003/00 |
Claims
1. A gas delivery device for supplying one or more predetermined
gases to a target environment, the device comprising a reservoir, a
gas diffusion portion for communicating gas from the reservoir and
one or more predetermined gases at concentrations other than
ambient levels are contained within the reservoir, wherein the
device does not generate gas.
2. The device according to claim 1, wherein the device may be
packaged prior to use with the one or more predetermined gases.
3. The device according to claim 1, wherein the reservoir is
substantially enveloped by a layer of material, and wherein the
layer of material is formed in a shape selected from the group
consisting of: a tube, a balloon, a ring, and a pouch.
4. The device according to claim 1, wherein the reservoir is
substantially enveloped by a layer of material, and wherein the
layer of material is formed into all or a portion of a contact
lens.
5. The device according to claim 1, wherein the reservoir comprises
a plurality of particles infused with the one or more predetermined
gases at concentrations greater than atmospheric.
6. The device according to claim 5, wherein the particles are
selected from the group consisting of reversible gas carriers such
as nanoparticles, beads, spheres, bubbles, pigments or
encapsulations, liposomes, oxygen transport pigments, hemoglobin
derivatives, derivatives of perflurocarbon and combinations
thereof.
7. The device of claim 1, wherein the gas diffusion portion
comprises at least a first portion of a wall of the reservoir.
8. The device of claim 7, wherein the at least a portion of the
wall is selected from the group consisting of: polyurethane,
silicone, polyvinylchloride, ethylene vinyl alcohol and
polyolefins.
9. The device of claim 7, wherein the at least a first portion of
the wall is porous and/or perforated.
10. The device of claim 9, wherein the at least a first portion of
the wall is porous and/or perforated in a manner sufficient to
allow non-gas entities to pass through.
11. The device of claim 10, wherein the non-gas entities comprise
nutritional or therapeutic agents
12. The device of claim 1, wherein the one or more predetermined
gases contained in the reservoir is controllably released to the
target environment through the gas diffusion portion.
13. The device of claim 1, further comprising an absorbent
layer.
14. The device of claim 1, wherein a compliant porous insert is
contained within the reservoir.
15. The device of claim 14, wherein the compliant porous insert is
comprised of a sponge-like and/or porous material.
16. The device of claim 14, wherein an absorbent layer is
incorporated into the compliant porous insert.
17. The device of claim 14, wherein the compliant porous insert
substantially fills the reservoir.
18. The device of claim 14, wherein a compliant porous insert is
incorporated in the absorbent layer
19. The device of claim 1, wherein the one or more predetermined
gases is selected from the group consisting of: oxygen, nitrogen,
carbon dioxide and nitric oxide.
20. The device of claim 1, wherein the reservoir further contains a
biologically beneficial agent.
21. The device of claim 20, wherein the biologically beneficial
agent is selected from the group consisting of: a drug, a mineral,
a nutrient, an amino acid, a pH modifier, an anti-microbial, a
growth factor and an enzyme.
22. The device of claim 20, wherein the biologically beneficial
agent is contained in microcapsules provided for on at least one of
the layers.
23. The device of claim 20, wherein the biologically beneficial
agent is contained in a gel matrix external to the reservoir.
24. The device of claim 1, wherein a wall of the reservoir
comprises a plurality of spaced apart ribs.
25. The device of claim 1, further comprising a substantially
gas-impermeable enclosed container containing the one or more
second predetermined gases and the device.
26. The device according to claim 1, wherein the one or more
predetermined gases are contained in a gas-infused gel provided
external to the reservoir.
27. The device according to claim 1, wherein the one or more
predetermined gases are contained in a gas-infused foam provided
external to the reservoir.
28. The device according to claim 1, further comprising a
septum.
29. A gas delivery device for supplying one or more predetermined
gases to a target environment, comprising a reservoir, a gas
diffusion portion for communicating gas from the reservoir and one
or more predetermined gases at concentrations other than ambient
contained within the reservoir, wherein the device does not
generate gas and may be packaged prior to use with the one or more
predetermined gases.
30. The device according to claim 29, wherein a preset volume of
the one or more predetermined gases are contained within the
reservoir.
31. The device according to claim 29, wherein the one or more
predetermined gases are included within the reservoir at about
atmospheric pressure.
32. The device according to claim 29, wherein the gas delivery
device is packaged prior to use at about atmospheric pressure.
33. The device according to any of claim 29, wherein the one or
more predetermined gases is selected from the group consisting of
oxygen, nitrogen, carbon-dioxide and nitric oxide.
34. The device according to claim 29, further comprising a
substantially gas-impermeable enclosed package for containing the
gas delivery device prior to use.
35. A gas delivery device for supplying one or more predetermined
gases to a target environment, the device comprising a reservoir, a
gas diffusion portion for communicating gas from the reservoir, one
or more predetermined gases at concentrations greater than
atmospheric contained within the reservoir, and a pressure release
port, wherein the device does not generate gas.
36. The device according to claim 35, wherein the pressure release
port comprises either a one-way or a two-way valve.
37. A pre-packaged gas-infused material for supplying one or more
predetermined gases to a target environment, the material
comprising one or both of a gas infused gel and a gas-infused
foam.
38. The material according to claim 37, wherein the gel and/or foam
gel is selected from the group consisting of: a hydrogel, an
acrylic resin, polyethylene glycol, polyacrylamide,
glucosaminoglycan, polyethylene oxide, and derivative and
combinations of the foregoing.
39. A method of packaging a gas delivery device comprising:
providing a gas delivery device for supplying one or more
predetermined gases to a target environment, the device comprising
a reservoir, a gas diffusion portion for communicating gas from the
reservoir and one or more predetermined gases at concentrations
greater than atmospheric contained within the reservoir, wherein
the device does not generate gas; placing the gas delivery device
into a package for containing the gas delivery device prior to use,
wherein the package capable of being substantially gas-impermeable
when sealed, and wherein the package includes a self-sealing
material; pressurizing the package with the one or more
predetermined gases immediately prior to or substantially
concurrently with the sealing of the package; puncturing the
package after a predetermined period of time has elapsed after
sealing the package, and applying a pressure to the outside of the
package to release excess one or more predetermined gases.
40. The method according to claim 40, wherein after the pressure to
the outside of the package is removed, the self-sealing material
seals the puncture.
41. The method according to claim 40, wherein the excess one or
more predetermined gases are released through a valve.
42. The method according to claim 41, wherein the valve comprises a
one-way valve mechanism.
43. The method f according to claim 42, wherein the one way valve
releases the excess one or more predetermined gases upon the
pressure in the package reaching a predetermined level.
44. The method according to claim 40, wherein immediately prior to
removing the pressure applied to the outside of the package to
release the excess one or more predetermined gases, the method
further includes re-sealing the package.
45. The method according to claim 44, wherein re-sealing the
package comprises heat-sealing.
46. A contact lens case comprising: a container holding at least
one contact lens and also for optionally holding contact lens
solution; and one or more predetermined gases at concentrations
greater than atmospheric included within the reservoir.
47. A contact lens oxygenation system comprising: a container for
holding a contact lens; an inlet for supplying a flow of oxygen to
the container; a supply of oxygen capable of providing a flow of
oxygen to the inlet; and an one-way valved outlet for releasing
excess pressure from the container.
48. A method for oxygenating a contact lens comprising: providing
at least one contact lens container for holding at least one
contact lens in a sealed state; positioning at least one contact
lens inside the at least one contact lens container; providing
oxygen to the inside of the at least one contact lens container in
concentrations greater than atmospheric.
49. The method according to claim 48, wherein providing oxygen
comprises establishing a flow of oxygen into the container.
50. The method according to claim 48, wherein the container
includes a one-way valve such that upon the flow of oxygen being
established excess pressure is released from within the container
upon the pressure reaching a predetermined level.
Description
RELATED APPLICATIONS
[0001] This application is a continuation-in-part (CIP) application
to U.S. published application, publication no. 2004/0260253 A1
(U.S. application Ser. No. 10/781,965) filed Feb. 18, 2004,
entitled, "Tissue Dressing Having Gas Reservoir", which claims
priority to U.S. Application Ser. No. 60/479,745, filed on Jun. 18,
2003. The present application also claims priority to U.S.
provisional patent application Nos. 60/654,037, filed Feb. 17,
2005, entitled, "Packaging Products with a Gas and Products For
Releasing the Gas Upon Use"; 60/662,019, filed Mar. 14, 2005,
entitled, "Methods and Apparatuses for Packaging Products with a
Gas"; and 60/711,796, filed Aug. 26, 2005, entitled, "Methods and
Applications related to Oxygen Charged Tissue Dressings". All of
the foregoing disclosures are herein incorporated by reference in
their entirety.
FIELD OF THE INVENTION
[0002] The present invention relates generally to devices (which
may also be referred to as apparatuses, systems or products) for
supplying/delivering one or more particular gases to a desired
area, use of such gas supplying devices, and systems and methods
for packaging such devices with one or more particular gases.
BACKGROUND OF THE INVENTION
[0003] This application includes citations to various publications,
patent applications and issued patents, each of which is herein
incorporated by reference in its entirety.
[0004] Oxygen's role in wound healing has been intensively studied.
In that regard, the background section of published parent no.
2004/0260253 A1 (the '253 publication) presents a discussion of
wound recovery with respect to oxygen supply and further teaches
how a simple dressing can supply oxygen to a wound area at high
concentrations without the need for producing oxygen chemically,
electrochemically or from a tethered source. In addition, devices
disclosed in the '253 publication allow for the delivery of other
gases at predetermined gas ratios to tissues and other target
areas. This simple means to manipulate and optimize local
environments can be used alone or in combination with other
materials and/or devices to create additive and sometimes
synergistic outcomes (e.g., heat, electrical stimulation, growth
factors, and nutrients), or using oxygen in combination with
antibiotics topically to enhance antimicrobial effectiveness.
SUMMARY OF THE INVENTION
[0005] In view of oxygen's benefits to speed healing and the
reduction of infection and pain for wounds, whether on the surface
or interior of tissues, embodiments of the present invention
include further means to supply oxygen, as well as other gases and
gas-ratios, to a wound on a continuous and ambulatory basis, as
well as other gases and gas ratios.
[0006] Beyond wounds, there are benefits to manipulating local
environments with one or more predetermined gases. Local
environments may be manipulated in order to accelerate growth of
cells, preserve or extend the life of cells and/or tissues, to
retard/maintain/accelerate biochemical reactions, to
sustain/accelerate/suppress chemical reactions, and the prevention
of corrosion. For example, attaching a gas emitting pouch to the
inside lid of a petri dish to preserve cells. In some cases, oxygen
may be released to manage metabolic processes, in other cases
carbon dioxide could be released (or a ratio of oxygen to carbon
dioxide, etc.). In still other cases, gas emitting devices may be
used as biocides to inhibit the growth of or kill organisms--like
the use of oxygen to kill anaerobic organisms or chlorine dioxide
to kill bacteria, fungi and algae. Some of the embodiments of the
present invention may include further means to supply gases and gas
ratios to a local area such as cells, tissues, containers, surfaces
and non-biological systems.
[0007] Accordingly, some embodiments of the invention include
methods and devices which saturate and/or super-saturate, absorb or
adsorb, or take up gases (hereinafter referred to as "gas
infusion", "gas infusing" or "gas infused") into a device with a
single gas (e.g., oxygen, carbon dioxide), or, in some embodiments,
infused with a plurality of gases. Such a device may become infused
with a subset of the gas(es) inside a sealed package by diffusing
passively from predetermined gas(es) stored in the package to the
device also stored in the package. This method can also be used to
preserve the gas levels precharged in or on a device by packaging
the device with gases that will maintain the predetermined gas
levels in the device. Upon opening the sealed package, the device
may be used to deliver the infused gas(es) to a target area. For
example, the product may be a medical related product such as a
topical dressing or implant infused with oxygen (for example) which
can then deliver oxygen to a target area of the body. An eye patch
or dressing, for example, could be applied to oxygenate the eye for
purposes such as to enhance healing or provide oxygen as a
nutrient.
[0008] Other examples of gas infused and gas emitting health care
products may include (but not limited to): injectables, topical
agents, contact lenses, implantable lenses, ingested devices,
inhaled materials, face masks, socks, boots, insoles, gloves,
sutures, pills, dermal fillers, wound healing gels, gum and the
like. These products may also contain other therapeutic materials
in addition to the infused gas, or may contain agents/ingredients
to facilitate the uptake and release of the gas(es). Such
embodiments may include a pre-packaged gas-infused gel and/or foam,
for supplying one or more predetermined gases to a target
environment.
[0009] Accordingly, some of the embodiments of the present
invention may include devices that are capable of providing one or
more predetermined gases to a target area ("a gas delivery
device"). Such embodiments may include one or more gas reservoirs
which may be formed between similar or dissimilar layers of
material or are enveloped within a continuous layer of
material.
[0010] In one embodiment, a multi-layer wound device ("dressing")
comes pre-filled with a predetermined amount of oxygen between the
layers. The top layer is a barrier film that holds the oxygen over
the wound, while the bottom layer is a gas permeable membrane,
which may be designed to have a specific rate of gas transfer. The
bottom layer is typically placed over the wound in some
applications, like conventional wound dressings, and can be
manufactured with a similar size, weight and feel of conventional
dressings or transdermal patches. The top or barrier layer retains
the oxygen in the vicinity of the wound, while the bottom or
permeable (or porous) layer allows the oxygen to diffuse into the
wound at a rate proportional to the gradient (for example), until
the wound is saturated. The dressing acts like a local abundant
oxygen supply to be used as needed. The geometry can be adjusted
from simple rectangular or circular packets to more complicated
geometries such as socks, gloves, masks and eye patches for wounds
located on the body where there are more contours, bends, crevasses
and protuberances.
[0011] Such a dressing according to some of the embodiments may be
provided to a user in a sealed package, and may be pre-filled with
a predetermined amount of one or more gases. In one embodiment, the
package is filled with a predetermined amount of one or more gases
(e.g., substantially pure oxygen--preferably 100% oxygen) which may
be accomplished using, for example, controlled atmospheric
packaging (CAP).When the gases in the reservoir are different in
type or concentration than gases sealed in the package, gases
diffuse through the permeable portion of the dressing until
reaching equilibrium when the gases and gas concentrations are the
same within the package and the reservoir. This passive diffusion
until equilibrium is a simple method to infuse or charge the
reservoir with the desired gas levels.
[0012] Another embodiment of the invention may include a gas
delivery device for supplying one or more predetermined gases to a
target environment, where the device may include a reservoir, a gas
diffusion portion for communicating gas from the reservoir and
include one or more predetermined gases. The device does not
generate gas and may be packaged prior to use with the one or more
predetermined gases. As in the previous embodiment, when the gases
in the reservoir are different in type or concentration than the
gases sealed in the package, gases may diffuse through the
permeable portion of the device until reaching equilibrium, when
the gases and gas concentrations are the same within the package
and the reservoir.
[0013] In another embodiment of the invention, a gas delivery
device for supplying one or more predetermined gases to a target
environment is provided, similar to the above-noted embodiment, and
also including a preset volume of one or more predetermined
gases.
[0014] Another embodiment of the invention includes a gas delivery
device which may be in the form of a contact lens for supplying one
or more predetermined gases like oxygen (for example) to a target
environment such as the cornea, retina or eye. Oxygen is stored
either between layers as gas, or as an oxygen saturated or oxygen
carrying solution between the layers and/or absorbed reversibly in
a lens material that lacks a reservoir between layers.
[0015] Other embodiments of the invention include devices having
one or more reservoirs (or designated areas of the device)
pre-filled with one or more predetermined gases (e.g., oxygen)
according to a predetermined amount corresponding to levels other
than that contained in the ambient atmosphere. The reservoir may be
formed between layers of material for such devices, or enveloped
within a continuous layer of material, or the material itself may
act as a reservoir as it contains gas either in its micro or macro
cavities (such as foam or gel) or by reversibly adsorbing or
absorbing gas molecules.
[0016] The gas infused products according to some embodiments fill
multiple micro-reservoirs with designated gas(es) by coming to
equilibrium with the gas for infusion during packaging or in the
package. In some embodiments, the gas permeates through the product
(e.g., a solid, semi-solid, fluid or semi-fluid), diffusing therein
(i.e., absorbed/adsorbed) by coming to equilibrium with the gas for
infusion in the package. In other embodiments, gas infusion of
products may be accomplished in the package at a temperature and/or
pressure greater than atmosphere in order to hasten or increase the
rate or levels of taken up by the product.
[0017] In another embodiment of the invention, a method of
packaging a gas delivery device is described that creates a flatter
package as one particular advantage. The gas delivery device may
comprise a reservoir including one or more predetermined gases, and
a gas diffusion portion for communicating the one or more
predetermined gases from the reservoir. The gas delivery device may
be packaged with the one or more predetermined gases that may or
may not be the same gas types or levels as contained in the
reservoir. Such a packaging method may include placing the gas
delivery device into a package, where the package capable of being
substantially gas-impermeable when sealed, and the package may be
filled with the one or more predetermined gases and sealed. Then,
after a predetermined period of time has elapsed, pressure is
applied to the outside of the package to release excess gas through
a port or a puncture, and then resealed either by a self sealing
design (self-sealing material included around the port or puncture)
or via an external operation (such as heat sealing). In another
embodiment, the port may allow gas to be removed without the need
for pressure being applied externally to the package.
[0018] In the above-noted embodiment, after the pressure to the
outside of the package is removed, the self-sealing material seals
the puncture. Alternatively or in addition thereto, the excess one
or more predetermined gases may be released through a valve, which
may be a one-way valve. Such valves may release the excess one or
more predetermined gases upon the pressure in the package reaching
a predetermined level.
[0019] Further to the above-noted embodiment, immediately prior to
removing the pressure applied to the outside of the package to
release the excess one or more predetermined gases, the method may
further include re-sealing the package (e.g., heat sealing).
[0020] Other embodiments of the invention may be directed to a
contact lens case which may include a container holding at least
one contact lens and also for optionally holding contact lens
solution and one or more predetermined gases at concentrations
greater than atmospheric included within the reservoir.
[0021] A related embodiment may include a contact lens oxygenation
system which may include a container for holding a contact lens, an
inlet for supplying a flow of oxygen to the container, a supply of
oxygen capable of providing a flow of oxygen to the inlet and a
one-way valved outlet for releasing excess pressure from the
container.
[0022] A further related embodiment may include a method for
oxygenating a contact lens which may include providing at least one
contact lens container for holding at least one contact lens in a
sealed state, positioning at least one contact lens inside the at
least one contact lens container, providing oxygen to the inside of
the at least one contact lens container in concentrations greater
than atmospheric or ambient pressure. Providing oxygen may include
establishing a flow of oxygen into the container. Moreover, the
container may include a one-way valve such that upon the flow of
oxygen being established excess pressure is released from within
the container upon the pressure reaching a predetermined level.
[0023] These and other embodiments, objects and advantages of the
system will become more apparent with reference to the following
detailed description and attached figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The accompanying drawings, which are incorporated in and
constitute a part of this specification, illustrate one embodiment
of the invention and, together with the description, explain one
embodiment of the invention. In the drawings,
[0025] FIG. 1 illustrates one embodiment of a dressing system.
[0026] FIG. 2 illustrates one embodiment of a packaging system.
[0027] FIG. 3 illustrates one embodiment of a gas emitting pouch
system.
[0028] FIG. 4 illustrates a flow diagram for utilizing a packaging
system according to one embodiment of the invention.
[0029] FIG. 5 illustrates a flow diagram for utilizing a dressing
system according to one embodiment of the invention.
[0030] FIG. 6 illustrates one embodiment of a pouch system.
[0031] FIGS. 7A is an illustration of a material for use in a
continuous-layer, gas-delivery device comprising a balloon.
[0032] FIG. 7B is an illustration of a material for use in a
continuous-layer, gas-delivery device comprising a tube.
[0033] FIG. 7C is an illustrations of a material for use in a
continuous-layer, gas-delivery device comprising a pouch.
[0034] FIG. 7D is an illustration of a material for use in a
continuous-layer, gas-delivery device comprising an O-ring.
[0035] FIG. 8 is an illustration of a gas-delivery device according
to an embodiment of the invention comprising a contact lens.
[0036] FIG. 9A is a first cross-sectional view of a packaging
system for packaging a gas-delivery device according to an
embodiment of the present invention.
[0037] FIG. 9B is a second cross-sectional view of a packaging
system for packaging a gas-delivery device according to an
embodiment of the present invention.
[0038] FIG. 9C is a third cross-sectional view of a packaging
system for packaging a gas-delivery device according to an
embodiment of the present invention.
[0039] FIG. 9D is a partial cross-sectional view of a packaging
system for packaging a gas-delivery device according to an
embodiment of the present invention utilizing a self-sealing
material.
[0040] FIG. 9E is a partial cross-sectional view of a packaging
system for packaging a gas-delivery device according to an
embodiment of the present invention utilizing a valve type
device.
[0041] FIG. 10 is a perspective view of a contact-lens case capable
of being charged with one or more predetermined gases, according to
one embodiment of the present invention.
DETAILED DESCRIPTION
[0042] FIG. 1 illustrates an example of one embodiment of the
invention of an apparatus for supplying one or more gases to a
target area. With reference to use of such an embodiment on
biological tissue, this embodiment may be referred to herein as a
tissue dressing system 100 (also known as a gas-delivery device).
The dressing system 100 is shown as an exemplary perspective
cut-away view for clearer understanding. The dressing system 100
may be configured to contain one or more predetermined gases. While
any one or more known gases (or volatiles) may be used, the gases
included with the dressing system 100 may particularly include
oxygen, carbon dioxide, nitrogen and nitric oxide, and combinations
thereof. The dressing system can also be used to supply gases to
any target areas that would benefit from a locally controlled gas
supply such as containers in which it is desired to retard,
accelerate, or maintain biochemical reactions, sustain, accelerate,
and/or suppress chemical reactions, corrosion, or inhibit the
growth or kill organisms,
[0043] The dressing system 100 may include a seal 110, an external
barrier (or top layer) 120, a reservoir 130, an absorbent ring 140,
an adhesive backing 150, a permeable film (or bottom layer) 160,
and a compliant porous insert 170. As shown, the reservoir may be
formed between the upper and lower layers (e.g., being hermetically
sealed around the perimeter), but may also be a separate element to
the dressing system, or contained within a continuous layer. To
that end, in one embodiment, the seal 110 is configured to bond the
external barrier 120 and the permeable film 160 together such that
the reservoir 130 is formed.
[0044] The external barrier 120 is preferably selected to be
non-permeable to gases. For example, the external barrier 120 may
be constructed of metallized polyester, ceramic coated polyester,
polyvinylidene chloride laminates such as Saranex.RTM., EVOH
laminates such as Oxyshield.RTM., or polyamide laminates such as
Capran.RTM.. In one embodiment, the external barrier 120 may be
configured to conduct heat or electrical stimulation from an
external source to the user. For example, polyethylene or another
infrared transmittable material may be utilized as the external
barrier 120.
[0045] The permeable film 160 is preferably configured to be
permeable to gases. For example, the permeable film 160 may be
constructed of polyurethane, silicone, polyvinylchloride,
polyolefins, and the like, preferably ethylene vinyl alcohol (EVA)
or EVA/polyethylene.
[0046] The reservoir 130 is configured to store a gas while the
dressing system 100 is worn by a user. In one embodiment, the
stored gas within the reservoir 130 is controllably released to the
user through the permeable film 160. The amount of gas released to
the user while wearing the dressing system 100 may vary according
to the concentration of the gas contained within the reservoir 130
and the material used as the permeable film 160. Other factors such
as temperature and atmospheric pressure may also affect the amount
of gas released to the user.
[0047] The absorbent ring 140 may be located adjacent to the
permeable film 160 and may be configured to wick away moisture from
the user. In addition, the adhesive backing 150 is configured to
adhere the dressing system 100 to the user. Further, the adhesive
backing 150 may also be utilized to prevent the gas that is
delivered through the permeable film 160 to the user from escaping.
In one embodiment, the adhesive backing 150 may cover the perimeter
of the dressing system 100. In another embodiment, the adhesive
backing may cover the entire dressing system 100 and may be
integrated with the permeable film 160. In another embodiment the
adhesive may be on the opposite side attaching the top film, for
example, to the inside lid surface of a container allowing the gas
to transfer through the bottom film over the entire volume of the
closed container such as a Petri dish.
[0048] Examples of the types of adhesive that may be used in the
present invention are described in U.S. Pat. Nos. 6,284,941 and
5,308,887. In one embodiment, the adhesive backing may be comprised
of adhesive used in commercially available adhesive bandages. In
another embodiment, the adhesive backing may be comprised of a gel
adhesive. The gel adhesive may be comprised of a hydrogel. The gel
adhesive may also be reusable, such that the dressing system could
be removed from the user and replaced more than once. Examples of
gels that may be used are described in U.S. Pat. Nos. 4,839,345,
5,354,790 and 5,583,114.
[0049] The compliant porous insert 170 is configured to prevent gas
debt in areas caused by pressing the external barrier 120 directly
on to the permeable film 160. In one embodiment, the compliant
porous insert 170 placed within the reservoir 130 and between the
external barrier 120 and the permeable film 160.
[0050] The proportions of gas-delivery device according to
embodiments of the present invention (e.g., dressing system 100 )
may be influenced by the diffusion rates of the relevant gases
through the permeable portion (e.g., film 160 ), the target gas
concentration range (e.g., on the user), and the length of time the
gas delivery device is used (e.g., the length of time the dressing
system 100 may be worn). If the gas-delivery device includes a
seal, then the proportions of the device may be also influenced by
the seal integrity between the dressing system 100 and the
user.
[0051] Some embodiments of the present invention for supplying one
or more gases to a target area may also include devices having a
continuous layer of gas permeable/porous material which, in some
aspects, envelops the one or more predetermined gases. As shown in
FIGS. 7A-7E, such continuous layer geometries may include a
balloon, a tube, an O-ring, a pouch, a teabag/sachet, a curved
material (e.g., a contact lens) or a combination of the foregoing.
Materials used for these various embodiments may depend on the
application--biocompatible or bioerodible materials can be used for
implantable sustained release devices
[0052] It is worth noting that some embodiments of the present
invention include gas infused devices having controlled and/or
customized gas diffusion rates. Specifically, such embodiments may
include pre-determined diffusion rates which may be determined by
controlling the type of membrane being used, the size and/or amount
of pores and/or erosion areas.
[0053] In some embodiments, in addition to providing gas to a
target area, the gas-delivery device may be configured to deliver
biologically beneficial agents such as drugs, minerals, nutrition,
amino acids, pH modifiers, anti-microbials (e.g., antibacterials
and antifungals), growth factors, and enzymes to the user. In one
embodiment, integrating the delivery systems of the gas with the
beneficial agent additives may lead to synergistic effects that are
not achieved by just the gas or the beneficial agent additives
alone. In one embodiment, these biologically beneficial agents may
be delivered as microencapsulated agents incorporated in the
adhesive backing 150. In another embodiment, the microencapsulated
agents may be available in a gel matrix in the dressing cavity 180,
accessible to the wound through pores or perforations, or using
conventional transdermal technologies.
[0054] In another embodiment, the dressing system as described
herein may further comprise a septum, which is defined herein as
any type of septum, valve, Luer-type fitting or any resealable
opening through which one or more gases can be introduced into the
dressing system, then resealed to prevent the one or more gases
from escaping. The dressing system of this embodiment may be
applied to the wound, then the one or more gases in the desired
ratio may be introduced into the dressing system, e.g., with a
syringe. The septum would also allow for refilling of the dressing
system, if desired.
[0055] FIG. 3 illustrates another embodiment according to the
present invention--a gas emitting pouch system 300. The gas
emitting pouch system 300 is shown as an exemplary perspective
cut-away view to more clearly illustrate the invention. In one
embodiment, the gas emitting pouch system 300 is configured to
contain a gas that is dispensed to the local area surrounding the
gas emitting pouch system 300. For example, the different gases
contained within the gas emitting pouch system 300 may include but
is not limited to oxygen, carbon dioxide, and/or nitrogen.
[0056] The gas emitting pouch system 300 may also include a first
permeable film 310, a second permeable film 320, and a reservoir
330.
[0057] In one embodiment, the first permeable film 310 is coupled
with the second permeable film 320 and forms the reservoir 330 for
storing gas within the gas emitting pouch system 300. For example,
the first and second permeable films 310 and 330 may be constructed
of the same or different materials such as polyurethane,
polyethylene, silicone films, polyvinylchloride, and the like.
[0058] The reservoir 330 is configured to store a gas while the gas
emitting pouch system 300 is being used. In one embodiment, the
stored gas within the reservoir 330 is controllably released to the
area surrounding the gas emitting pouch system 300 through the
first and second permeable films 310 and 320.
[0059] The amount and rate of gas released through the gas emitting
pouch system 300 may vary according to the concentration gradients
of the gas across the permeable films that comprise the walls of
reservoir 330 and the materials used as the first and second
permeable films 310 and 320. 310 and 320 can be the same or
different materials. The amount and rate of release of gas can be
different on the opposite sides, this can occur when 310 and 320
have different permeabilities. Other factors such as temperature,
humidity and atmospheric pressure may also affect the amount of gas
released.
[0060] The elements comprising the gas emitting pouch system 300
are shown for illustrative purposes only. Deletion or substitution
of any shown elements does not depart from the spirit and scope of
the invention. Similarly, the addition of new elements does not
depart from the spirit and scope of the invention.
[0061] In one embodiment, the gas emitting pouch system 300 is
configured prefilled with the desired gas concentrations and is
stored within the packaging system 200 (FIG. 2) prior to releasing
gas into the surrounding environment, also prefilled with the same
gas concentrations as in the gas emitting pouch, in order to
maintain the levels in the pouch. In another embodiment, the gas
within the reservoir 330 within the gas emitting pouch system 300
comes to equilibrium within the packaging system 200 so that both
the pouch and the package reach the target concentrations.
[0062] In one embodiment, the gas emitting pouch system 300 is
configured to be placed in an environment where the gas stored
within the reservoir 330 is released steadily into the surrounding
environment, as the gradient doesn't change appreciably. In another
embodiment, the release rate of gas from the reservoir 330 into the
surrounding environment slows as the surrounding environment
becomes saturated with the gas. Subsequent to the saturation, the
gas emitting pouch system 300 acts as a gas reservoir; as gas is
dissipated from the surrounding environment, there is a local
supply of gas within the reservoir 330 to be provided to the
surrounding environment, governed by the transfer rate across the
permeable film.
[0063] The gas emitting pouch 300 has many applications which may
include non-medical applications such as applying the gas emitting
pouch 300 to effect environments in containers for any purpose such
as lab experiments, food preservation, to accelerate degradation,
to prevent corrosion, and the like.
[0064] FIG. 6 illustrates another example of a pouch system. The
pouch system 600 is configured to emit gas into a local
environment, similar to the gas emitting pouch system 300. The
pouch system 600 includes a first layer 610 and a second layer 630.
The first layer 610 and the second layer 630 may be permeable to
gases. In one embodiment, the first layer 610 and the second layer
630 are bonded through an intermediate layer 620. The intermediate
layer 620 provides the pouch system 600 a more resilient and
durable seal between the first layer 610 and the second layer 630
by diverting the load so that more robust shear force is applied to
a higher bond strength seal rather than strictly a design that puts
all the internal pressure and load on a peel strength surface. By
adding the intermediate layer 620 with a narrower diameter than the
first layer 610, the seal between the first layer 610 and the
second layer 630 is reinforced.
[0065] Packaging
[0066] One method of achieving the specified oxygen concentration
in the reservoir 130 and to create the controlled atmospheric
packaging is to (1) assemble dressing, sealing the reservoir with
normal atmospheric conditions (about 21% oxygen); (2) place the
dressing in a package (e.g., a metallized film package); (3) flush
the package with substantially pure oxygen; and (4) sealing the
package. In storage, the gas in the reservoir 130 will come to
equilibrium with the gas in the package via the permeable film 160.
When the package is received by the customer and opened, the gas in
the reservoir will achieve about 95-98% oxygen. The materials and
dimensions used are determined by taking into account these
objectives. The final concentration in the reservoir depends upon
the volume and ratios of gases. For example, a dressing containing
about 10 cc of air in the reservoir placed in a package which is
filled with about 200 cc oxygen will equilibrate at a final oxygen
concentration of approximately 96% 202 .times. cc .times. .times.
.times. oxygen 210 .times. .times. total .times. .times. .times. cc
.times. .times. gas = 96 .times. % ##EQU1##
[0067] FIG. 2 illustrates an exemplary packaging system 200. The
packaging system 200 is shown as an exemplary perspective cut-away
view to more clearly illustrate the invention. In one embodiment,
the packaging system 200 is configured to contain a gas within an
enclosed container 210, which is within the packaging system. For
example, the different gases contained within the dressing system
100 may include but is not limited to oxygen, carbon dioxide,
nitrogen, and/or nitric oxide.
[0068] The enclosed container 210 may also be configured to hold
the dressing system 100 as shown and described corresponding to
FIG. 1. Once the enclosed container 210 is sealed, the enclosed
container is substantially impermeable; the gas within the enclosed
container 210 substantially remains within the enclosed container
210. Further, the enclosed container 210 utilizes controlled
atmospheric packaging (CAP) to maintain the environment within the
enclosed container 210. In one embodiment, CAP is a package with
high barrier properties that contains the desired ratio of gases to
preserve the internal environment. The gas within the enclosed
container 210 may permeate the dressing system 100 through the
permeable film 160.
[0069] In still other embodiments, a hole may be created in the
dressing system (preferably on one side of the dressing, and
preferably on the permeable side of the dressing), and the dressing
placed in the package. The package is then evacuated which also
evacuates the reservoir. The package is then filled with the one or
more desired gases (e.g., oxygen) and sealed. Thereafter, the
reservoir in the dressing fills with the gases contained in the
package. The time it takes for the oxygen to enter the reservoir
may be between less than a minute to several hours, and more
preferably between about several minutes and several hours. It
suffices to say, by the time the packaged dressing is sold, the
reservoir contains sufficient amount of the packaged gases to
supply a wound or other use. The hole in the dressing is sized so
that upon opening of the package and removal/use of the dressing, a
negligible amount of oxygen is released from the reservoir prior to
application to the intended target area.
[0070] In some embodiments, to achieve desired gas concentration
levels, CAP gas amounts in the package are sufficiently high so as
to create a bulky package. For example, packaging for a wound
dressing may be inflated with at least oxygen gas, causing the
package to expand such that the package is bulky and much larger
than the wound dressing. After a period of time sufficient enough
to allow the oxygen to penetrate the dressing the remaining gas or
a portion of the gas may be removed from the package. This allows
the final package to be smaller and thus, shipped and distributed
more easily.
[0071] The packaging system 200 may be utilized to store the
dressing system 100 without degrading the gas stored within the
reservoir 130 within the dressing system 100 when the gas within
the reservoir 130 and the gas within the enclosed container 210 are
the same.
[0072] The packaging system 200 may be utilized to change the
concentrations of gases in the dressing system 100. The gas
constituents stored within the enclosed container 210, diffuse into
the dressing system 100 when the concentration of the gas within
the container 210 is higher in concentration compared to the gas
within the dressing system 100. Similarly, the gas constituents
stored within the dressing system 100, diffuse into the container
210 when the concentration of the gas within the container 210 is
lower in concentration compared to the gas within the dressing
system 100. The gases may diffuse through the permeable film 160
until the constituents reach equilibrium, the same concentrations
on both sides of the permeable film. In other embodiments, gas
infusion may be accomplished in a barrier package at a temperature
and/or pressure greater than atmosphere in order to hasten or
increase the levels of taken up by a device.
[0073] Another embodiment of the packaging system comprises any of
the packaging systems described herein and further comprises a
septum, which as defined herein may be a septum, a valve, Luer lock
or any resealable opening, through which one or more gases can be
introduced into the packaging system, then resealed to prevent
gases from escaping. The packaging system may be charged with the
one or more gases in the desired ratio on site (e.g., hospital,
doctor's office).
[0074] The flow diagram in FIG. 4 illustrates an exemplary process
of utilizing the packaging system 200 according to one
embodiment.
[0075] In Block 410, a gas-retaining object is placed within the
packaging system 200. In one embodiment, the gas-retaining object
is the dressing system 100. In another embodiment, the
gas-retaining object is gas emitting pouch system 300. In yet
another embodiment, the gas-retaining object may be any item that
is configured to retain and controllably release a gas from the
object.
[0076] In Block 420, the packaging system 200 is flushed with a
gas. In one embodiment, the packaging system 200 is flushed with
the same gas contained with the gas-retaining object. For example,
the dressing system 100 may be pre-filled with oxygen and placed
within the packaging system. By flushing the packaging system 200
with oxygen, the packaging system 200 ensures that the dressing
system 100 retains the pre-filled oxygen content.
[0077] In another embodiment, the packaging system 200 is flushed
with a different gas than the gas contained with the gas-retaining
object. For example, the dressing system 100 may contain air that
contains other gases in addition to oxygen and may be placed within
the packaging system 200. By flushing the packaging system 200 with
pure oxygen, the packaging system 200 diffuses the dressing system
100 with additional oxygen until the gas within the packaging
system 200 and the gas within the dressing system 100 have reached
an equilibrium.
[0078] In Block 430, the packaging system 200 is sealed after
placing the gas-retaining object within the packaging system 200
and flushing the packaging system 200 with a gas.
[0079] In Block 440, if the gas within the gas retaining device and
the gas within the packaging system 200 differ, then an exchange of
gas occurs until an equilibrium is achieved. For example, by using
the above example describing a dressing system I 00 that contains
air which is sealed within the packaging system 200 flushed with
pure oxygen, the oxygen diffuses into within the dressing system
100, while nitrogen diffuses out of the dressing system 100 into
the package 200 until an equilibrium is achieved between the gas
within the dressing system 100 and the packaging system 200. In
this embodiment, the gas may be exchanged through the permeable
film 160 (FIG. 1).
[0080] In Block 450, the packaging system 200 may be opened to
remove the gas-retaining object. The packaging system 200 may be
utilized to store the gas-retaining object without degrading the
gas within the gas-retaining object. In another embodiment, the
packaging system 200 may be utilized to infuse the gas-retaining
object with a gas.
[0081] Mechanisms for carrying out the removal of remaining gases
(or a portion thereof) from the packaging may include devices such
as a rubber septum or a self-sealing material provided for on a
wall of the package. As shown in FIG. 9D, located on the interior
(or between layers if multiple layers of material are used) the
wall 902 of the package includes a self-sealing material 904. The
self-sealing material allows a puncture through a wall of the
package to self-seal, preferably after excess gas has escaped from
the puncture. For example, after pressurization, and after a
packaged device has absorbed a specified gas or gases (and may have
also absorbed other therapeutic materials), the package is
punctured and pressure is applied to the package to force out the
remaining materials (e.g., gases and or therapeutic materials)
which have not been absorbed by the device. After the package has
decreased in size, the puncture device (e.g., a needle) may be
removed and the force on the package is released. The puncture hole
is then sealed from the flow of the self-sealing material.
Alternatively, the package may be vented and re-sealed as shown in
FIGS. 9A-9C. Specifically, as shown in FIG. 9A, a puncture device
906 may be used to puncture a wall 908 of the package which
contains a gas delivery device 910. As shown, the ends 912 may be
heat sealed.
[0082] FIG. 9B illustrates gas excess gas(es) escaping out of the
puncture hole 914 (arrows B), which may be driven by pressure
(arrows A) applied to the package. Thereafter, the end of the
package may be heat sealed at a location of the puncture 914 which
eliminates the puncture/vent from the final package.
[0083] Alternative to the above (or in addition thereto) the
package may include a one-way valve 916 on a wall 918 of the
package as shown in FIG. 9E. The valve may comprise one or more
flaps 920 which allow one-way travel of gas--i.e., out of the
package. Upon the device having absorbed the gas(es) and/or other
therapeutic agents, pressure may be applied to the outside of the
package which forces the valve 916 open and the excess agent out of
the package.
[0084] Use of a Tissue Dressing System
[0085] The flow diagram in FIG. 5 illustrates an exemplary process
of utilizing the dressing system 100 according to one embodiment.
Accordingly, in Block 510, the dressing system 100 is removed from
a packaging.
[0086] In Block 520, the dressing system 100 is adhered to a user.
In one embodiment, the dressing system 100 may cover a wound or
broken skin of the user. In one embodiment, the dressing system 100
utilizes the adhesive backing 150 to adhere the dressing system 100
to the user.
[0087] In Block 530, a seal is formed between the dressing system
100 and the user. In one embodiment, the adhesive backing 150 forms
the seal between the dressing system 100 and the user.
[0088] In Block 540, gas is supplied from the dressing system 100
to the user. In one embodiment, the permeable film 160 is
positioned over the wound or broken skin of the user and allows the
gas from the dressing system 100 to be supplied to wound of the
user.
[0089] In another embodiment, the permeable film 160 may be
positioned over intact skin of the user and allows the gas from the
dressing system 100 to be supplied to the skin of the user. There
are numerous practical applications in supplying oxygen to intact
skin such as treating sun or radiation damaged skin, exfoliated
skin, dermabraded skin, or providing nourishment to aged skin.
There may be a synergistic effect with topical agents as well.
[0090] In Block 550, the gas within the reservoir 130 of the
dressing system 100 may be stored until additional gas is supplied
to the user through the permeable film 160.
[0091] Ophthalmologic Embodiments.
[0092] Contact Lens Oxygenation. In another group of embodiments, a
method and system for oxygenating or re-oxygenating contact lenses
between uses is provided. Specifically, these embodiments include
taking one or more contact lenses and placing them into a container
that may be charged (and/or re-charged) with oxygen (or another
specific gas or gases). Accordingly, users may then be able to
oxygenate their own contact lenses. The lenses may be inserted into
the case, for example, by popping them thru a gentle one way valve,
or, alternatively, the lenses may be placed in a contact lens case
and the case may then be oxygenated--either by inflating a
collapsed case or flushing oxygen thru a rigid case (for example).
The rigid case, accordingly, may include a venting mechanism for
escaped gas.
[0093] FIG. 10 illustrates an example of a contact lens case 1000
having a re-sealable port 1002a and 1002b, to which oxygen source
1004 can be flowed into. One-way valve vents 1006a and 1006b allows
gases to flow out of each respective chamber of the contact lens
case so as to insure fresh oxygen from oxygen source 1004 is
contained in each chamber. These embodiments may, in addition to
being used for contact lenses, also be used to oxygenate contacts
that are used as "bandage lenses" after photorefractive keratectomy
laser surgery for nearsightedness (for example). Keratectomy is a
procedure where the outer cell layer of the cornea is removed,
resulting in a wound that is a large abrasion on the eye, which is
extremely painful to the patient. Accordingly, such bandage lenses
are used as a protective covering on the cornea once anesthetic
wears off.
[0094] Oxygen can be supplied a variety of ways to the contact lens
case/container: e.g., via compressed oxygen stored in a cylinder or
spray-can, or in prefilled, non-pressurized oxygen packages that
allow the user to insert the device without leaking oxygen, and
then open the package. Moreover, some embodiments of the invention
may include contact-lens cases which include a reservoir of oxygen
that, release oxygen to the area in which the contact lens is
stored.
[0095] Other Embodiments
[0096] Still other embodiments of the invention include uses and
methods for charging gas carrying media, such as oxygenating oxygen
carrier gels, foams or solutions. For example, placing these
materials into an impermeable package and filling the package with
the predetermined gas, these materials become charged or saturated
with gas while inside the package. Whether gases are supplied via a
reservoir created between a barrier layer and a gas-permeable layer
or through a gas-permeable continuous layer, the one or more gases
may be stored in micro- or nano-reservoirs. These multiplicative
reversible gas carrying reservoirs may include, for example, micro-
or nano-particles, beads, spheres, mems (microelectro-mechanical
systems), pigments or liposomes, for delivery to the target area.
Further descriptions of such materials (e.g., repirocytes) can be
found at: [0097] www.foresight.org/Nanomedicine/Respirocytes.html,
and [0098]
www.foresight.org/Nanomedicine/Respirocytes1.html#Sec22.
[0099] One form of respirocyte includes "molecular sorting rotors"
which have been described by Drexler K E. Nanosystems: Molecular
Machinery, Manufacturing, and Computation. New York: John Wiley
& Sons, 1992. These tiny rotors have binding site "pockets"
along their rims that are exposed alternately to the gas source to
deliver or infuse gas from or into an interior microchamber. Once
the binding site rotates to expose it to the interior chamber, the
bound molecules are forcibly ejected by rods thrust outward by the
cam surface. This can work equivalently in the reverse direction by
ejecting gas after interior chamber has been charged with gas.
These theoretical respirocytes can be designed to precisely take on
and dispense oxygen and carbon dioxide separately or simultaneously
under various conditions). Other reversible oxygen carriers include
transport pigments which are conjugated proteins, or proteins
complexed with another organic molecule or with one or more metal
atoms. Transport pigments contain metal atoms such as Cu.sup.2+ or
Fe.sup.3+. Besides hemoglobin and myoglobin, other natural oxygen
carriers include hemocyanin, a blue copper-based pigment found in
molluscs and crustaceans and chlorocruorin, a green iron-based
pigment found in marine polychaete worms, and different oxides of
vanadium. Other reversible oxygen-carriers include cobalt-based
porphyrins such as coboglobin (a cobalt-based analog to hemoglobin)
and cobaltodihistidine, and other metallic porphyrins, iron-indigo
compounds, iridium complexes such as
chloro-carbonyl-bis(triphenylphosphine)-iridium, a cobalt/ammonia
complex described by (Hearon J Z, Burke D, Schade A L.
Physicochemical studies of reversible and irreversible complexes of
cobalt, histidine, and molecular oxygen. J Natl Cancer Inst 1949;
9:337-377), zeolite-bound divalent chromium, nonporphyrin lacunar
iron complexes, and heme-linked NADPH oxidase.
[0100] Still other embodiments may include a device which includes
a semi-solid, fluid or semi-fluid, gas infused material (i.e., gas
being absorbed/adsorbed). Such semi-solid or semi-fluid products
may include a gel, an ointment or a foam which is infused with one
or more gases. Such materials may be cast on a film, and positioned
over a wound or proximate a target where the desired gas(es) is to
be provided. Such materials also may, as indicated above, be
contained in a reservoir. Gel/foam materials may include but are
not limited to hydrogels, acrylic resins, polyethylene glycols (or
derivatives or cocktails thereof), polyacrylamide,
glcosaminoglycan, polyethylene oxide, carboxymethyl-chitin
hydrogel, poly(vinyl alcohol), nitric oxide releasing hydrogels,
chitosan hydrogel, hydrogen peroxide gels, wound healing gels,
bioerodible HEMA hydrogels, drug delivery gels (see for example
Cox, Charles, "Treatment Options Gel With Innovative Drug Delivery
Systems", Drug Delivery Technology
(http://www.drugdeliverytech.com/cgi-bin/articles.cgi?idArticle=55);
Eisenbud, D et al., "Hydrogel Wound Dressings: where do we stand in
2003?", pp. 52-57, Ostomy Wound Manage, October 2003; Chiellini,
Federica et al., "Bioerodible hydrogels based on 2-hydroxyethyl
methacrylate: Synthesis and characterization", Journal of Applied
Polymer Science, ISSN 0021-8995, Vol. 85, pp. 2729-2741 (2002).
Each of the foregoing references is incorporated herein by
reference in its entirety.
[0101] Materials infused with one or more predetermined gases,
whether micro/nano particles or beads, gels, foams or combination
thereof may also be bio-compatible and/or bio-resorbable materials.
The term "bioresorbable materials" refers to a group of materials
that have been shown to clinically resorb in living tissue (e.g.,
the human body), and include such products as sutures, dermal
fillers and bone fillers (for example). According, such
gas-delivery devices according to some embodiments of the present
invention, when implanted into tissue (e.g., bone, cartilage,
subdermal fat), biodegrade as they release (or when upon releasing
a majority of) its stored gas such as oxygen or nitric oxide.
Accordingly, such bioresorbable materials can include calcium
phosphates, hydroxyapatite, apatites, calcium sulfates,
bioresorbable polymers, collagen, gelatin, and bioactive glass.
Calcium phosphates include alpha-tri-calcium phosphate and
beta-tri-calcium phosphate.
[0102] Still other embodiments of the invention include uses and
methods for storing and/or preserving oxygen media, tissue, and/or
cells (e.g., red-blood cells), as well as uses and methods for
oxygenating oxygen carrier solutions. Such solutions may include
perfluorocarbons, polyhemoglobins, molecularly modified hemoglobin,
and oxygenated Krebs solution.
[0103] Still other embodiments of the invention include methods to
oxygenate scaffolds, tissues, artificial skin that may contain
fibrinogen, collagen, hemoglobin, myoglobin, or other reversible
oxygen binding agents for use as wound or aesthetic dressings. By
placing these materials into a package and filling the package with
oxygen, these materials become saturated with oxygen within the
package and then upon application to the tissue, release that
oxygen over time depending on the design and local oxygen
demand.
[0104] The foregoing descriptions of specific embodiments of the
invention have been presented for purposes of illustration and
description. They are not intended to be exhaustive or to limit the
invention to the precise embodiments disclosed, and naturally many
modifications and variations are possible in light of the above
teaching. The embodiments were chosen and described in order to
explain the principles of the invention and its practical
application, to thereby enable others skilled in the art to best
utilize the invention and various embodiments with various
modifications as are suited to the particular use contemplated.
* * * * *
References