U.S. patent application number 09/731318 was filed with the patent office on 2001-10-18 for receptacles to facilitate the extraction of powders.
Invention is credited to Clark, Andrew, Paboojian, Steve, Schuler, Carlos.
Application Number | 20010029947 09/731318 |
Document ID | / |
Family ID | 22627201 |
Filed Date | 2001-10-18 |
United States Patent
Application |
20010029947 |
Kind Code |
A1 |
Paboojian, Steve ; et
al. |
October 18, 2001 |
Receptacles to facilitate the extraction of powders
Abstract
A receptacle for holding fine powders comprises a receptacle
body that defines an enclosed cavity. The receptacle body has a top
end and a bottom end. Further, the bottom end of the receptacle
body includes a raised central region that extends upwardly into
the cavity. In this way, the flow of air through the cavity will
remain generally adjacent the walls of the cavity until exiting
through an extraction tube.
Inventors: |
Paboojian, Steve; (Menlo
Park, CA) ; Schuler, Carlos; (Cupertino, CA) ;
Clark, Andrew; (Half Moon Bay, CA) |
Correspondence
Address: |
TOWNSEND AND TOWNSEND AND CREW
TWO EMBARCADERO CENTER
EIGHTH FLOOR
SAN FRANCISCO
CA
94111-3834
US
|
Family ID: |
22627201 |
Appl. No.: |
09/731318 |
Filed: |
December 6, 2000 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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60172317 |
Dec 17, 1999 |
|
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|
Current U.S.
Class: |
128/203.15 |
Current CPC
Class: |
B05B 11/062 20130101;
A61M 15/0028 20130101; A61M 15/0036 20140204; A61M 2202/064
20130101; A61M 15/002 20140204; B05B 7/1413 20130101; A61M 11/001
20140204; A61M 2205/073 20130101; A61M 15/0041 20140204; B65D
75/366 20130101; B65D 2575/362 20130101 |
Class at
Publication: |
128/203.15 |
International
Class: |
B05D 007/14; A61M
015/00; A61M 016/00; B65D 083/06 |
Claims
What is claimed is:
1. A receptacle for holding fine powders, the receptacle
comprising: a receptacle body that defines an enclosed cavity,
wherein the receptacle body has a top end and a bottom end, and
wherein the bottom end of the receptacle body includes a raised
central region that extends upwardly into the cavity.
2. A receptacle as in claim 1, wherein the receptacle body further
comprises at least one curved wall that in combination with the
raised central region forms a generally semi-toroidal geometry in
the cavity.
3. A receptacle as in claim 1, wherein a portion of the bottom end
is flat in geometry.
4. A receptacle as in claim 1, wherein the receptacle body further
includes a tab extending from the cavity
5. A receptacle as in claim 1, further comprising a central hole in
the top end and multiple vents, and a cover removably attached to
the top end to cover the hole and the vents.
6. A method for aerosolizing a powder, the method comprising:
providing a receptacle having a top end, a bottom end, and a cavity
containing a powder; inserting a bottom end of an extraction tube
into the cavity such that the bottom end of the extraction tube is
spaced above the bottom end of the receptacle; forming at least one
vent in the cavity; forming a hole in the bottom end of the cavity;
and flowing a gas stream through the hole in the bottom end of the
receptacle and through at least a portion of the extraction tube to
cause air to be drawn through the vent and then through the cavity
to move the powder in the cavity into the extraction tube where the
powder is entrained in the high pressure gas stream to form an
aerosol.
7. A method as in claim 6, wherein the bottom end of the receptacle
includes a raised central region that extends upwardly into the
cavity, and further comprising aligning the extraction tube with
the raised central region such that the bottom end of the
extraction tube is spaced apart from the raised central region.
8. A method as in claim 6, further comprising capturing the
aerosolized powder in a capture chamber.
9. A method as in claim 6, further comprising forming multiple
vents in the top end of the receptacle about a periphery of the
cavity such that air is drawn through substantially all of the
cavity to remove the powder.
10. A method as in claim 6, further comprising forming tabs in the
top end of the receptacle body that extend into the cavity to
create a vortex within the cavity as the air flows through the
cavity.
11. A method as in claim 6, further comprising a patient inhaling
to produce the gas stream.
12. A method as in claim 6, further comprising releasing an amount
of pressurized gas to produce the gas stream.
13. A method for aerosolizing a powdered medicament, the method
comprising: providing a receptacle comprising a receptacle body
that defines an enclosed cavity, wherein the receptacle body has a
top end and a bottom end, and wherein the bottom end of the
receptacle body includes a raised central region that extends
upwardly into the cavity; inserting a bottom end of an extraction
tube into the cavity such that the bottom end of the extraction
tube is aligned with the raised central region and is spaced above
the bottom end of the receptacle; forming vents in the top end of
the receptacle about a periphery of the cavity; and flowing a gas
stream through a least a portion of the extraction tube to draw air
through the vents and then through the cavity to move the powder in
the cavity into the extraction tube where the powder is entrained
in the gas stream to form an aerosol.
14. A method as in claim 13, wherein the receptacle includes a
curved wall, and wherein the air flows along the wall to remove
substantially all powder from the receptacle.
15. A method as in claim 13, wherein the air drawn by the gas
stream flows through a flow area, and further comprising reducing
the flow area as the air flows through the receptacle and the
extraction tube to accelerate the flow of air through the
receptacle.
16. A method as in claim 15, wherein the vents form a first flow
area, wherein a gap between the extraction tube and the bottom end
of the receptacle defines a second flow area, and wherein a cross
section of the extraction tube defines a third flow area, and
wherein the first flow area is greater than the second flow area,
and wherein the second flow area is greater than the third flow
area.
17. A method as in claim 16, wherein the ratio of the first flow
area to the second flow area and to the third flow area is about
2.0:1.5:1.0.
18. A method as in claim 13, further comprising piercing a hole
through the top end of the receptacle and inserting the extraction
tube into the cavity through the hole in the top end.
19. A method as in claim 13, further comprising introducing the gas
stream into the extraction tube at a location spaced apart from the
bottom end of the extraction tube.
20. A method as in claim 13, further comprising forming a hole in
the bottom end of the receptacle body, and flowing the gas stream
through the hole in the bottom end.
21. A method as in claim 13, further comprising a patient inhaling
to produce the gas stream.
22. A method as in claim 13, further comprising releasing an amount
of pressurized gas to produce the gas stream.
23. A method for aerosolizing a powdered medicament, the method
comprising: providing a receptacle comprising a receptacle body
that defines an enclosed cavity, wherein the receptacle body has a
top end and a bottom end; inserting a bottom end of an extraction
tube into the cavity such that the bottom end of the extraction
tube is spaced above the bottom end of the receptacle; forming
vents in the top end of the receptacle about a periphery of the
cavity; and flowing a gas stream through a least a portion of the
extraction tube to draw air through the vents and then through the
cavity to move the powder in the cavity into the extraction tube
where the powder is entrained in the gas stream to form an aerosol;
and wherein the air drawn by the gas stream flows through a flow
area, and further comprising reducing the flow area as the air
flows through the receptacle and the extraction tube to accelerate
the flow of air through the receptacle.
24. A method as in claim 23, further comprising a patient inhaling
to produce the gas stream.
25. A method as in claim 23, further comprising releasing an amount
of pressurized gas to produce the gas stream.
26. A method as in claim 23, wherein the vents form a first flow
area, wherein a gap between the extraction tube and the bottom end
of the receptacle defines a second flow area, and wherein a cross
section of the extraction tube defines a third flow area, and
wherein the first flow area is greater than the second flow area,
and wherein the second flow area is greater than the third flow
area.
27. A method as in claim 23, wherein the receptacle further
comprises a curved wall, and wherein the bottom end of the
receptacle body includes a raised central region that extends
upwardly into the cavity to provide a generally laminar air flow
along the wall.
28. An apparatus for aerosolizing a powdered medicament, the
apparatus comprising: a housing having a holder that is adapted to
receive a receptacle having a cavity that holds a powder; a
piercing mechanism that is adapted to pierce a hole in a bottom end
of the receptacle; a vent forming mechanism for forming multiple
vents in a top end of the receptacle; and an extraction tube that
is adapted to be placed into the cavity so as to be spaced above
the bottom end of the receptacle and to be aligned with the hole in
the bottom end.
29. An apparatus as in claim 28, further comprising a mouthpiece
coupled to the housing that is adapted to receive a patient's mouth
to permit the patient to produce a gas stream that is flowed
through the hole in the bottom end of the receptacle and into
extraction tube to draw the powder from the cavity and into the
extraction tube where the powder is entrained in the gas stream to
form an aerosol
30. An apparatus as in claim 28, further comprising a flow insert
to control spacing of the extraction tube relative to the
receptacle.
31. A system for aerosolizing a powdered medicament, the system
comprising: at least one receptacle that comprises a receptacle
body that defines an enclosed cavity, wherein the receptacle body
has a top end and a bottom end, and wherein the bottom end of the
receptacle body includes a raised central region that extends
upwardly into the cavity; and an aerosolizing apparatus having a
holder for holding the receptacle, an extraction tube that is
insertable into the cavity, a vent forming device to form multiple
vents in the top end of the receptacle about a periphery of the
cavity.
32. A system as in claim 32, further comprising a pressure source
for producing a high pressure gas stream within at least a portion
of the extraction tube to draw air through the vents to move the
powder from the cavity and into the extraction tube where the
powder is entrained in the high pressure gas stream to form an
aerosol.
33. A system as in claim 32, further comprising a flow insert to
control spacing of the extraction tube relative to the
receptacle.
34. A system as in claim 32, wherein a portion of the bottom end of
the receptacle is flat in geometry.
35. A powder extraction system, comprising: at least one receptacle
that defines an enclosed cavity that holds a powder, wherein the
receptacle has a top end and a bottom end; a holder to hold the
receptacle; an extraction tube that is insertable into the cavity;
a vent forming device to form vents in the top end of the
receptacle, wherein the vents form a first flow area, wherein a gap
between the extraction tube and the bottom end of the receptacle
defines a second flow area, and wherein a cross section of the
extraction tube defines a third flow area, and wherein the holder
is configured to move the receptacle relative to the bottom end of
the extraction tube such that the first flow area is greater than
the second flow area, and wherein the second flow area is greater
than the third flow area to accelerate a gas flowing through the
receptacle.
36. A system as in claim 36, further comprising a pressure source
for producing a high pressure gas stream within at least a portion
of the extraction tube to draw air through the vents to move the
powder from the cavity and into the extraction tube where the
powder is entrained in the high pressure gas stream to form an
aerosol
37. A system as in claim 36, wherein the receptacle includes a
curved wall, and wherein the bottom end of the receptacle includes
a raised central region that extends upwardly into the cavity.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation in part application and
claims the benefit of U.S. Provisional Patent Application No.
60/172,317, filed Dec. 17, 1999, the complete disclosure of which
is herein incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] This invention relates generally to the field of drug
delivery, and in particular to the pulmonary delivery of powdered
medicaments. More specifically, the invention relates to techniques
for extracting powdered medicaments from receptacles during the
aerosolizing process.
[0003] One promising way to deliver various drugs to a patient is
by pulmonary delivery where a drug dispersion or aerosol is inhaled
by the patient to permit the active drug within the dispersion to
reach the distal or alveolar regions of the lung. Pulmonary drug
delivery has shown to be particularly promising because certain
drugs have been found to readily absorb within the blood
circulation. For example, pulmonary delivery may be a useful
approach for proteins and polypeptides that are difficult to
deliver by other routes of administration.
[0004] A variety of techniques have been employed to deliver drugs
to the lungs including liquid nebulizers, metered dose inhalers,
and the like. Of particular interest to the invention are dry
powder dispersion devices that are able to aerosolize powdered
medicaments for inhalation by the patient. Exemplary apparatus for
aerosolizing powdered medicaments are described in U.S. Pat. Nos.
5,458,135, 5,775,320, 5,740,794 and 5,785,049, and copending U.S.
patent application Ser. No. 09/004,558, filed Jan. 8, 1998, Ser.
No. 09/312,434, filed Jun. 4, 1999, Ser. No. 60/136,518, filed May
28, 1999, and Ser. No. 60/141,793, filed Jun. 30, 1999, the
complete disclosures of which are herein incorporated by
reference.
[0005] At least some of the apparatus described in the above
references utilize a high pressure gas stream to draw the powder
into an extraction tube where the powder is deagglomerated,
entrained in the high pressure gas stream, and exits as an aerosol
suitable for inhalation. In some cases, such apparatus may utilize
a receptacle that has a penetrable lid. The extraction tube is
inserted through the lid and a vent is also formed in the lid. The
high pressure gas stream then draws air through the receptacle and
into the extraction tube. The air drawn through the receptacle
extracts the powder where it joins with the high pressure gas
stream to form the aerosol.
[0006] This invention is related to alternative ways to extract
powder from receptacles that store the powder. The invention also
relates to the design of such receptacles to facilitate removal of
the powder.
SUMMARY OF THE INVENTION
[0007] In one embodiment, the invention provides an exemplary
receptacle for holding fine powders. The receptacle comprises a
receptacle body that defines an enclosed cavity for holding the
powder. The receptacle body has a top end and a bottom end, and the
cavity is configured to facilitate extraction of substantially all
of the powder when air or another gas is drawn through the cavity.
For example, in one aspect, the bottom end of the receptacle body
includes a raised central region that extends upwardly into the
cavity. Such a configuration is advantageous in that it permits the
flow of air to remain adjacent to an inner wall of the cavity until
being drawn into an extraction tube. In this way, a generally
laminar flow of air is provided across the walls of the cavity
until reaching the extraction tube to provide a generally uniform
shear stress across the walls. In this manner, the flow of air
serves as a "scrubber" to remove powder from the walls where it may
be drawn into the extraction tube.
[0008] In one aspect, the curved interior wall in combination with
the raised central region forms a generally semi-toroidal geometry
in the cavity. With such a configuration, as the air is drawn
through the cavity, it adheres to the walls and flows smoothly up
the raised central region and into the extraction tube.
Alternatively, the walls may be curved to form a "bow tie"
configuration. Conveniently, a portion of the bottom end of the
receptacle may be flat in geometry to facilitate convenient resting
of the receptacle on a flat surface and accurate vertical
positioning of the receptacle. In another aspect, the receptacle
body may comprise a pair of opposing curved walls and a pair of
opposing generally planar walls that at least partially form the
cavity. Conveniently, the receptacle body may further include a tab
that extends from the cavity to facilitate handling of the
receptacle, e.g., such as when inserting the receptacle into an
aerosolizing device.
[0009] The invention further provides an exemplary method for
aerosolizing a powdered medicament. The method utilizes a
receptacle having an enclosed cavity for holding the powder. The
receptacle further includes a raised central region that extends
upwardly into the cavity. According to the method, a bottom end of
an extraction tube is inserted into the cavity such that the bottom
end of the extraction tube is aligned with the raised central
region and is spaced above the bottom end of the receptacle. Vents
are formed in the top end of the receptacle about a periphery of a
cavity, and a gas stream is flowed through at least a portion of
the extraction tube to draw air through the vents and then through
the cavity to move the powder in the cavity into the extraction
tube where the powder is entrained in the high pressure gas stream
to form an aerosol. Use of the raised central region is
advantageous in that it channels or funnels the air toward the
extraction tube to prevent powder from remaining in the center of
the cavity.
[0010] In one aspect, the receptacle has one or more curved
interior walls. In this way, the air flows along the wall along
substantially the entire length of the cavity to remove
substantially all powder from the receptacle. By providing a wall
with a continuous curvature, the momentum of the flowing air is
changed which causes the air flow to stay adjacent the wall,
causing powder adjacent the wall to be drawn into the extraction
tube.
[0011] In another aspect, the air drawn by the gas stream flows
through a flow area that becomes progressively smaller. In this
way, the air is accelerated as it flows through the receptacle and
into the extraction tube to further assist in removing
substantially all of the powder from the receptacle.
[0012] In still another aspect, a hole is pierced through the top
end of the receptacle to permit the extraction tube to be inserted
into the cavity through the hole in the top end. In one option, the
gas stream may be introduced into the extraction tube at a location
spaced apart from the bottom end of the extraction tube. Further,
the gas stream may be introduced at an acute angle relative to a
central axis of the extraction tube. In this way, the area of flow
through the receptacle and the extraction tube may be controlled to
accelerate the air through the receptacle. Alternatively, a hole
may be formed in the bottom end of the receptacle body, and the gas
stream may be flowed through the hole in the bottom end and then
through the extraction tube, with outside air being drawn into the
cavity through one or more vents to move the powder into the
extraction tube. In another aspect, a flow insert may be provided
to control spacing of the extraction tube relative to the
receptacle. In this way, the area of flow through the receptacle
and the extraction tube may be controlled to accelerate the air
through the receptacle.
[0013] In one alternative, an amount of pressurized gas is released
to produce a high pressure gas stream that is utilized to extract
the powder from the receptacle. Alternatively, the gas stream may
be produced by the patient's own inhalation, i.e. breath
actuation.
[0014] In another embodiment, the invention provides a method for
aerosolizing a powdered medicament that utilizes a receptacle
having an enclosed cavity for holding the powder. An extraction
tube is inserted into the cavity such that a bottom end of the
extraction tube is spaced above the bottom end of the receptacle.
Vents are formed in the top end of the receptacle and a high
pressure gas stream is flowed through at least a portion of the
extraction tube to draw air through the vents and then into the
cavity to remove the powder. Alternatively, a gas stream created by
the patient's own inhalation may be flowed through the extraction
tube to remove the powder. As the air is drawn through the
receptacle and then into the extraction tube, the area of flow is
progressively reduced to accelerate the flow of air through the
receptacle.
[0015] For example, in one aspect, the vents may form a first flow
area, and a gap between the extraction tube and the bottom end of
the receptacle may define a second flow area. Further, a
cross-section of the extraction tube may define a third flow area.
The first flow area is constructed to be larger than the second
flow area, and the second flow area is constructed to be larger
than the third flow area. Conveniently, the receptacle may include
a curved interior wall and a raised central region that extends
upwardly into the cavity so that a generally laminar flow of air
may be produced along the wall in a manner similar to that
previously described.
[0016] The invention further provides an exemplary method for
aerosolizing a powder that utilizes a receptacle having a cavity
that contains the powder. A bottom end of an extraction tube is
inserted into the cavity such that the bottom end of the extraction
tube is spaced above the bottom end of the receptacle. At least one
vent is formed in the cavity, and a hole is formed in the bottom of
the cavity such that the hole is generally aligned with the bottom
end of the extraction tube. A gas stream is then flowed through the
hole in the bottom end of the receptacle and then through the
extraction tube to cause air to be drawn through the vent and then
through the cavity to move powder in the cavity into the extraction
tube where the powder is entrained in the gas stream to form an
aerosol.
[0017] In one aspect, the aerosolized powder is captured in a
capture chamber where it is available for inhalation by a patient.
The method may utilize various features described in connection
with other embodiments of the invention. For example, the
receptacle may include a raised central region that extends
upwardly into the cavity and is generally aligned with the
extraction tube. Further, multiple vents may be formed in the top
of the receptacle about a periphery of a cavity to draw air into
substantially all of the cavity. Tabs or foils may also be formed
in the top of the receptacle that extend into the cavity to create
a vortex within the cavity as the air flows through the cavity.
Conveniently, the gas stream may be produced by releasing an amount
of gas from a pressured gas source, or may be produced by the
patient's own inhalation.
[0018] In another embodiment, an apparatus is provided for
aerosolizing a powdered medicament. The apparatus comprises a
housing having a holder for holding a receptacle having a cavity
that contains the powder. A piercing mechanism is provided to
pierce a hole in a bottom end of the receptacle, and a vent forming
mechanism is provided to form multiple vents in the top of the
receptacle. An extraction tube is further provided and may be
placed into the cavity so as to be spaced above the bottom end of
the receptacle and to be aligned with the hole in the bottom end. A
pressure source or the patient's own inhalation may be utilized to
produce a gas stream that is flowed through the hole in the bottom
end of the receptacle and into the extraction tube. In so doing,
outside air is drawn into the cavity and moves the powder from the
cavity and into the extraction tube where the powder is entrained
in the gas stream to form an aerosol. Conveniently, the vent
forming mechanism may be configured to produce multiple vents that
are spaced about a periphery of the receptacle.
[0019] In a further embodiment, a system is provided for
aerosolizing a powdered medicament. The system comprises at least
one receptacle that defines an enclosed cavity. The receptacle
further includes a raised central region that extends upwardly into
the cavity. An aerosolization apparatus is further provided having
a holder for holding the receptacle. The aerosolizing apparatus
further includes an extraction tube that is insertable into the
cavity, a vent forming device to form multiple vents in the top end
of the receptacle about a periphery of the cavity, and a pressure
source for producing a high pressure gas stream within at least a
portion of the extraction tube. Alternatively, the patient's own
inhalation may be used to produce a gas stream. In this way, air
may be drawn through the vents to move the powder from the cavity
into the extraction tube where the powder is entrained in the gas
stream to form an aerosol.
[0020] In one aspect, a flow insert may be provided to control
spacing of the extraction tube relative to the receptacle. Further,
the flow insert in combination with the vents and the extraction
tube may be employed to accelerate the flow of air through the
receptacle. For example, the vents may be configured to form a
first flow area, and a gap between the extraction tube and the
bottom end of the receptacle may define a second flow area. A
cross-section of the extraction tube may define a third flow area.
In this way, the holder may be configured to move the receptacle
relative to the bottom end of the extraction tube, or vice versa,
such that the first flow area is greater than the second flow area,
and the second flow area is greater than the third flow area.
[0021] In still another aspect, curved tabs or foils may be
preformed in the top end of the receptacle body to create a vortex
within the cavity as the air flows through the cavity. In this way,
removal of substantially all the powder from the receptacle is
facilitated. In another aspect, a portion of the bottom end of the
receptacle may be flat in geometry to facilitate its placement onto
the holder.
[0022] In one alternative aspect, the receptacle may have a
preformed central hole and vents about the periphery of the cavity.
A cover may be removably attached to the top end of the receptacle.
In this way, after the receptacle has been inserted into the
aerosolizing apparatus, the cover may be pulled from the receptacle
to permit the extraction tube to be inserted into the central hole
and to expose the vents.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1 is a top view of one embodiment of a receptacle for
holding a powder according to the invention.
[0024] FIG. 2 is a cross sectional side view of the receptacle of
FIG. 1, taken along lines 2-2.
[0025] FIG. 3 is a perspective view of the receptacle of FIG. 1
showing vents formed in a top end and an extraction tube that has
been inserted into the top end according to one embodiment of the
invention.
[0026] FIG. 4 is a schematic side view of an exemplary method for
extracting powder from the receptacle of FIG. 3 according to the
invention.
[0027] FIG. 5 is a partial top view of another embodiment of a
receptacle having curved tabs or foils to produce a vortex in the
receptacle when extracting powder according to the invention.
[0028] FIG. 6 is a partial cross sectional side view of one of the
tabs of the receptacle of FIG. 5.
[0029] FIG. 7 is a top view of an alternative embodiment of a
receptacle according to the invention.
[0030] FIG. 8A is a cross sectional side view of the receptacle of
FIG. 7 taken along lines A-A.
[0031] FIG. 8B is a cross sectional side view of the receptacle of
FIG. 7 taken along lines B-B.
[0032] FIG. 9 is a perspective view of a receptacle into which an
extraction tube is inserted and illustrates the various flow areas
through which the air flows when extracting the powder from the
receptacle according to the invention.
[0033] FIG. 10 is a schematic side view of one embodiment of an
aerosolizing device that may be employed to aerosolize a powder
according to the invention.
[0034] FIG. 11 is a schematic side view of a receptacle and an
extraction tube and illustrates an alternative technique for
extracting the powder according to the invention.
[0035] FIG. 12 is a schematic side view of an alternative
embodiment of an aerosolizing device according to the
invention.
[0036] FIG. 13 is a top view of still another alternative
embodiment of a receptacle having a removable cover according to
the invention.
[0037] FIG. 14 is a cross sectional side view of the receptacle of
FIG. 13.
[0038] FIG. 15 is a schematic side view of a breath actuated
aerosolizing device according to the invention.
DESCRIPTION OF THE SPECIFIC EMBODIMENTS
[0039] The invention provides exemplary techniques and equipment
for extracting powder that is held within a receptacle, typically
within a sealed cavity. In one aspect, the powder extracted is
entrained in a high pressure gas stream to aerosolize the powder so
that it will be suitable for inhalation by a patient. The invention
may be utilized with essentially any type of receptacle within
which the powder is sealed. Merely by way of example, one type of
receptacle that may be utilized with the invention are widely
available "blister packs". Examples of other types of receptacles
are described in U.S. Pat. No. 5,740,794, previously incorporated
by reference. However, it will be appreciated that the invention is
not intended to be limited to these specific types of
receptacles.
[0040] The powders of the invention may be extracted by creating an
opening or access way into the receptacle and then flowing air or
other gases through the receptacle to move the powder out of the
access way. Conveniently, one or more vents may also be created in
the receptacle to facilitate the flow of air through the
receptacle. One exemplary way to draw air through the receptacle is
by use of an extraction tube that is inserted into the cavity. A
high pressure gas stream is flowed through at least a portion of
the extraction tube to cause air in the receptacle to be drawn into
the bottom end of the extraction tube where the powder is entrained
in the high pressure gas stream to form an aerosol. Examples of
techniques that employ the use of such an extraction tube are
described in U.S. Pat. No. 5,740,794, previously incorporated by
reference. Further, a variety of techniques may be employed to
create the high pressure gas stream to cause the air to be drawn
through the receptacle. For example, various techniques for
producing the high pressure gas stream are described in U.S. Pat.
No. 5,740,794 and copending U.S. patent application Ser. Nos.
09/004,558, 09/312,434, 60/136,518 and 60/141,793, previously
incorporated herein by reference. Gases that may be used to produce
the gas stream include air, CO.sub.2, HFCs, CFCs, and the like.
[0041] To draw air through the receptacle and into the bottom end
of the extraction tube, the high pressure gas stream may be
introduced into the extraction tube at a location that is spaced
apart from the bottom end. For example, the high pressure gas
stream may be introduced into the extraction tube at an acute angle
as described generally in U.S. Pat. No. 5,740,794, previously
incorporated by reference. Alternatively, a hole may be formed in
the bottom end of the receptacle along with one or more vents, and
the extraction tube inserted into the top end of the receptacle so
that it is generally aligned with the hole. The high pressure gas
stream may then be flowed through the hole and into the extraction
tube to cause air to be drawn through the vents, through the
receptacle and into the bottom end of the extraction tube.
[0042] Alternatively, the invention may utilize a patient's own
inhalation to produce a gas stream. For example, the invention may
utilize a mouthpiece over which the patient's mouth is placed. As
the patient inhales, a vacuum is created to produce a gas stream
that flows through the receptacle as described above.
[0043] A variety of schemes may be employed, alone or in
combination, to facilitate the extraction of the powder using air
flowing through the receptacle. For example, one technique employs
the use of air or other gases to uniformly "scrub" the sides of the
cavity. More specifically, the air may be flowed adjacent an
interior wall or walls until the air exits the receptacle through
the extraction tube. In this way, a shear stress is provided along
substantially the entire length of the interior wall to assist in
removing any powder that adheres to the wall so that it may be
moved into the extraction tube. The walls may be constructed with a
variety of geometries to facilitate a laminar flow across the walls
so that the flow will not become separated from the walls as it
flows through the receptacle. In this way, a uniform, "scrubbing"
of the walls is provided. Merely by way of example, one convenient
way to form the walls is to provide them with a degree of curvature
so that they continuously curve up to the extraction tube. Such a
continuous curved surface allows for a laminar flow along
substantially the entire length of the walls and up to the
extraction tube. The curvature of the walls also tends to induce
instabilities that are manifested as a plurality of
counter-rotating vortices, sometimes referred to as Taylor-Goertler
vortices, having axes of rotation locally parallel to the curved
walls. These vortices serve to scrub the walls of powder.
Conveniently, the receptacle may include a raised region at a
center of the receptacle so that the walls slope up to the
extraction tube. In this way, no dead space is provided in the
middle of the receptacle and the flow remains adjacent to the walls
until exiting through the extraction tube.
[0044] Another technique to facilitate removal of the powder is to
accelerate the flow of air through the receptacle. One convenient
way to accelerate the air flow is to progressively decrease the
area through which the air passes as it flows through the
receptacle and out of the extraction tube. By progressively
reducing the flow area, the air is accelerated as it flows through
the receptacle and into the extraction tube.
[0045] Still another technique for facilitating the removal of the
powder is to create a vortex in the cavity to permit the air to
sweep the sides of the receptacle as it spins through the cavity
and up into the extraction tube. Conveniently, curved edges, tabs
or foils may be formed in the top end of the receptacle to initiate
the vortex when air is drawn into the receptacle.
[0046] Another feature of the invention is that the receptacles may
be constructed to have preformed holes and/or vents. In this way,
the top surface of the receptacle does not need to be pierced when
inserting the extraction tube or forming the vents. Conveniently, a
removable cover may be placed on top of the receptacle. After
insertion into an aerosolizing apparatus, the cover may be pulled
from the receptacle to expose the holes and/or vents. The
extraction tube may then be inserted into the receptacle and the
powder extracted as described herein.
[0047] Referring now to FIGS. 1 and 2, one embodiment of a
receptacle 10 will be described. Receptacle 10 comprises a
receptacle body 12 having a top end 14 and a bottom end 16 (see
FIG. 2). Conveniently, a tab 18 may be provided to facilitate
handling of receptacle 10. Receptacle body 12 defines a cavity 20
into which a powder is sealed. Conveniently, receptacle body 12 may
be constructed from essentially any type of material that is
compatible with the powder held within cavity 20. Examples of
materials that may be used include metals, such as aluminum,
composites, plastics, and the like. One convenient way to construct
receptacle 10 is to provide a thin strip of metal or composite and
then pressing cavity 20 using a dye. Another thin strip of metal
may then be attached to the strip having the cavity to enclose and
seal the cavity. Conveniently, ultrasonic welding or heat sealings
may be employed to adhere the two metal strips together. However,
it will be appreciated that other techniques and materials may be
employed to construct receptacle 10. Further, a number of
receptacles may be formed as a single string for multi-dose
aerosolizers.
[0048] Cavity 20 has a generally circular outer periphery 22 and is
formed of a continuously curved wall 24 that forms a raised central
region 26 at or near a center of the receptacle. In this way, a
generally semi-toroidal interior is formed.
[0049] Referring now to FIG. 3, an extraction tube 28 is shown
inserted into cavity 20. Extraction tube 28 has a bottom end 30
that is generally aligned with raised central region 26 when
inserted into receptacle 10. Conveniently, bottom end 30 of
extraction tube 28 may include a sharpened edge to facilitate its
entry into cavity 20. Alternatively, a preformed hole may be formed
in top end 14 to permit entry of extraction tube 28 into cavity 20.
Bottom end 30 is positioned so that it is spaced apart from bottom
end 16 of cavity 20. In this way, a gap is provided between bottom
end 30 and bottom end 16 to permit air to flow between the gap.
Also shown in FIG. 3 are a plurality of vents 32 that are formed
about periphery 22. In one aspect, vents 32 may be formed such that
they are spaced close to each other in an attempt to form an
annulus about periphery 22. In this way, air may be introduced into
cavity 20 about essentially the entire periphery 22.
[0050] Referring now to FIG. 4, one technique for extracting powder
from receptacle 10 using extraction tube 28 will be described. A
high pressure gas stream (not shown) is flowed past a portion of
extraction tube 28 at a location spaced above bottom end 30 as
described generally in U.S. Pat. No. 5,740,794, previously
incorporated by reference. This causes air to be drawn into
receptacle 10 through vents 32 as illustrated by the arrows. The
air is flowed through cavity 20 until entering bottom end 30 where
it proceeds through extraction tube 28. Eventually, the air
containing the powder is joined with the high pressure gas stream
that deagglomerates the powder and entrains the powder in the gas
stream to form an aerosol.
[0051] As shown in FIG. 4, wall 24 has a continuous curvature so
that the air flowing through cavity 20 remains generally adjacent
wall 24 with a laminar flow. In this way, a shear stress is created
along substantially the entire length of wall 24 to remove any
adhered powder along wall 24. Further, central region 26 directs
the air up to bottom end 30 so that essentially no dead volume
exists within cavity 20. In this manner, substantially all the
powder is drawn into extraction tube 30. It will be appreciated
that the size of cavity 20 as well as the degree of curvature of
wall 24 may be varied depending on a variety of features,
including, for example, the volume and rate of air flow through
cavity 20, the amount and type of powder held within cavity 20, and
the like.
[0052] Referring now to FIGS. 5 and 6, another embodiment of a
receptacle 34 will be described. Receptacle 34 comprises a
receptacle body 36 that forms a cavity 38 (shown in phantom line).
Cavity 38 has a generally circular outer periphery 40 and may
optionally include a raised central region as described in
connection with other embodiments. Formed in a top end 42 of
receptacle body 36 are a plurality of vents 44. A central hole 46
is also formed in top end 42 and is configured to receive an
extraction tube. In this way, air may be drawn through vents 44,
through cavity 38, and into the extraction tube where it is
extracted from the receptacle in a manner similar to that
previously described with other embodiments.
[0053] One feature of receptacle 34 is that it includes curved
foils 48 at each of the vents 44. As best shown in FIG. 6, foils 48
extend into cavity 38 so as to produce a vortex within cavity 38
when air is drawn in through vents 44. This is illustrated
generally by the arrows in FIG. 5. By creating a vortex within
cavity 38, the air flow is swirled around the interior walls that
define cavity 38 to assist in removing powder that is adhered to
the walls. Advantageously, the vortex results in an acceleration of
the air to further assist in removing powder from the receptacle.
Further, large powder agglomerates within cavity 38 may be caught
in the vortex and thrown radially outward because of centripetal
acceleration coincident with their larger mass relative to smaller
powder particles. In this way, the larger agglomerates are
statistically more likely to strike the side of the tube to induce
deagglommeration.
[0054] FIGS. 7, 8A and 8B illustrate another embodiment of a
receptacle 50. Receptacle 50 comprises a receptacle body 52 having
a top end 54, a bottom end 56 and a tab 58. Receptacle body 52
defines a cavity 60 into which a powder is held. Cavity 60 is
defined by two side walls 62 and two end walls 64 to form a "bow
tie" configuration. A raised central region 66 extends up into
cavity 60 in a manner similar to raised central region 26 of
receptacle 10.
[0055] To extract powder from receptacle 50, an extraction tube
(not shown) may be inserted through top end 54 and aligned above
raised central region 66 in a manner similar to that previously
described in connection with receptacle 10. Vents may then be
formed in top end 54 adjacent curved walls 64. In this manner, air
will be drawn through the vents and along curved wall 64 where the
air will be funneled by raised central region 66 into the bottom
end of the extraction tube. By providing curved walls 64, the air
flow will tend to flow along the walls to assist in removing powder
that adheres to the walls in a manner similar to that previously
described in connection with receptacle 10.
[0056] Another technique that may be employed to facilitate
extraction of the powder is by accelerating the flow of air through
the cavity. FIG. 9 illustrates one technique for accelerating the
flow of air through the cavity. Shown in FIG. 9 is a receptacle 68
comprising a receptacle body 70 having a top end 72 and a bottom
end 74. Receptacle body 68 forms a cavity 76 that is defined by an
interior wall 78. Cavity 76 may be configured to be generally open
or may have a raised central region as previously described in
connection with other embodiments. A plurality of vents 79 are
formed in top end 72 about a periphery of cavity 76. A center hole
80 is also provided in top end 72 to permit an extraction tube 82
to be inserted into cavity 76 as shown. Extraction tube 82 has a
bottom end 84 and a top end 86. Optionally, extraction tube 82 may
have a reduced cross sectional area at top end 86 to facilitate
aerosolization of the powder as described generally in U.S. Pat.
No. 5,740,794, previously incorporated by reference. Although not
shown, it will be appreciated that a high pressure gas stream may
be flowed past a portion of extraction tube 82 at a location spaced
apart from bottom end 84 in a manner similar to that previously
described. Alternatively, the high pressure gas stream may be
flowed through a hole in bottom end 74 and then into extraction
tube 82, as described hereinafter. In either case, the use of such
a high pressure gas stream causes air to be drawn into cavity 76
through vents 79 where the powder is moved into extraction tube 82
through its bottom end 84 where it is entrained in the high
pressure gas stream and aerosolized.
[0057] Each of vents 79 forms a flow area A.sub.i. When summed
together, areas A.sub.i form a total input flow area A.sub.I. As
the air passes through cavity 76, it flows through a gap created
between bottom end 84 of extraction tube 82 and bottom end 74 of
cavity 76. This flow area may be calculated by multiplying the
distance of the gap by the circumference of extraction tube 82 at
bottom end 84. This area is referred to as the gap area A.sub.G. As
the air flows through extraction tube 82, the flow area is
restricted near top end 86 as shown. This area is the cross
sectional area A.sub.O of the extraction tube. To accelerate the
flow of air through cavity 76, areas A.sub.I, A.sub.G and A.sub.O
may be configured such that A.sub.I>A.sub.G>A.sub.O. In this
way, the flow area is progressively decreased as it passes through
the system. As such, the flow of air is accelerated as it passes
through cavity 76. Although a variety of area ratios may be
employed, one particular ratio is where A.sub.I=2, A.sub.G=1.5, and
A.sub.O=1. However, it will be appreciated that other ratios may be
employed.
[0058] Referring now to FIG. 10, one embodiment of an
aerosolization apparatus 90 will be described. Apparatus 90
comprises a base 92 that forms a housing for various components of
apparatus 90. Enclosed in base 92 is a holder 94 for holding a
receptacle. For convenience of illustration, receptacle 10 of FIG.
1 is shown held within base 92. However, it will be appreciated
that other types of receptacles may be utilized with apparatus 90.
A button 96 is provided on holder 94 to permit holder 94 to move up
and down within base 92 as indicated by the arrows. As shown,
holder 94 has a generally flat surface. As previously described,
receptacle body 12 may be included with a flat portion on bottom
end 16 to facilitate its placement onto holder 94. However, it will
be appreciated that holder 94 may be constructed to have different
geometries to facilitate holding of receptacle 10, as well as to
facilitate introduction and removal of receptacle 10.
[0059] Positioned above receptacle 10 is an aerosolizing mechanism
98 that includes an extraction tube 100 that is insertable into
cavity 20 of receptacle 10. Optionally, a bottom end 102 of
extraction tube 100 may include a sharpened edge or other piercing
structure to form a hole in the top end of receptacle 10 to
facilitate its introduction into cavity 20. Joining extraction tube
100 at an acute angle relative to a central axis of extraction tube
100 (and relative to bottom end 102) are a pair of channels 104. A
pressure source 106 is employed to produce a high pressure gas
stream within channels 104. The high pressure gas stream is
introduced into extraction tube 100 to cause air to be drawn into
bottom end 102 from cavity 20 as described generally in U.S. Pat.
No. 5,740,794, previously incorporated herein by reference.
Pressure source 106 may be any one of a variety of pressure
sources, including manually activated pistons, compressed gases,
fluorocarbons, and the like as described generally in the patents
and patent applications previously incorporated herein by
reference. Hence, it will be appreciated that pressure source 106
is merely being shown schematically for convenience of
illustration. Although not shown, an actuating mechanism may be
employed to release the pressurized gas from pressure source 106
when a patient is ready to produce the aerosolized medicament.
[0060] Aerosolization mechanism 98 includes a bottom end 108 that
serves as a stop or a flow insert to control the gap between bottom
end 102 of extraction tube 100 relative to bottom end 16 of
receptacle 10. In this way, when button 96 is moved upward, the top
end of receptacle 10 will engage bottom end 108 to fix the distance
of extraction tube 100 relative to the bottom end of receptacle 10.
Use of such a flow insert is advantageous in that the gap area
A.sub.G (see FIG. 9) may be precisely controlled to facilitate the
acceleration of air through cavity 20 in a manner similar to that
previously described in connection with FIG. 9.
[0061] Extending from bottom end 108 are a plurality of piercing
elements 110 that are configured to produce vents in receptacle 10
about the periphery of cavity 20. In this way, air may be drawn
through the vents when the high pressure gases stream is released
from pressure source 106.
[0062] Coupled to base 92 is a capture chamber 112. Capture chamber
112 is configured to capture the aerosolized medicament exiting
extraction tube 100 in a manner similar to that described in
connection with the patents and patent applications incorporated
herein by reference. Capture chamber 112 includes a mouthpiece 114
through which the patient may inhale the captured medicament.
[0063] Hence, apparatus 90 may be employed to aerosolize a
medicament by inserting receptacle 10 into base 92. Holder 94 is
then raised to insert extraction tube 102 into cavity 20 and to
cause piercing elements 110 to form vents in receptacle 10.
Pressure source 106 is actuated to release an amount of pressurized
gas which causes air to be drawn into and through the vents and
along the walls of cavity 20 until entering into extraction tube
100. As the powder is moved into extraction tube 100, it encounters
the high pressure gas stream which deagglomerates the powder and
ejects the powder into capture chamber 112 in an aerosolized form.
Although holder 94 is shown to move vertically upward, it will be
appreciated that extraction tube 100 and/or piercing elements 110
may be configured to be moved downward to be inserted into cavity
20. Further, alternative aerosolizing mechanisms 98 may be employed
as described herein.
[0064] Referring now to FIG. 11, an alternative technique for
drawing air through a receptacle to move powder within the
receptacle into an extraction tube will be described. Shown
schematically in FIG. 11 is a receptacle 116 having a top end 118
and a bottom end 120. Receptacle 116 includes a cavity 122 having a
raised central region 124. However, it will be appreciated that the
technique described in connection with FIG. 11 may be employed with
other cavity designs, including those that do not utilize a raised
central region. A plurality of vents 126 are formed in top end 118
to permit air to be drawn into cavity 122. An extraction tube 128
is inserted into cavity 122, with a bottom end 130 being spaced
apart from raised central region 124 as shown. A bottom hole 132 is
formed in bottom end 120 of receptacle 116. In this way, a high
pressure gas stream may be flowed through bottom hole 132 and then
through bottom end 130 of extraction tube 128, as shown by the
arrows. In so doing, air is drawn through vents 126 and through
cavity 122 where it enters bottom end 130 of extraction tube 128 as
shown by the arrows. As the air flows through cavity 122, it moves
the powder into extraction tube 128 in a manner similar to that
previously described in connection with other embodiments.
[0065] Shown schematically in FIG. 12 is an aerosolizing apparatus
134 that may be employed to aerosolize a powdered medicament using
the techniques just described in connection with FIG. 11. Apparatus
134 comprises a base 136 having a holder 138 for holding a
receptacle 140. Holder 138 includes a knob 142 to permit receptacle
140 to be moved up and down as shown by the arrows. Also included
within base 136 is an extraction tube 144 having a bottom end 146.
By moving knob 142, extraction tube 144 may be inserted into
receptacle 140 as shown. Alternatively, extraction tube 144 may be
constructed to be movable so that it may be moved into receptacle
140.
[0066] Positioned below holder 138 is a pressure source 148 and an
introduction tube 150. Pressure source 148 and/or introduction tube
150 may be moved vertically upward as illustrated by the arrows to
pierce receptacle 140 and insert introduction tube 150 into or
adjacent to receptacle 140. An amount of pressurized gas may then
be released from pressure source 150 where it flows through the
hole in the bottom end of receptacle 140 and into bottom end 146 of
extraction tube 144. As one alternative, holder 142 may be lowered
while pressure source 148 is kept stationary to form the hole in
the bottom end of receptacle 140. Although not shown, it will be
appreciated that a piercing mechanism may be employed to form one
or more vents in receptacle 140 (or receptacle 140 may include
pre-formed vents). In this way, outside air may flow into the
receptacle through the vents to assist in moving powder into tube
144.
[0067] Positioned on base 136 is a capture chamber 152 having a
mouthpiece 154. With such a configuration, receptacle 140 may be
placed into holder 138 and extraction tube 144 inserted into
receptacle 140. A hole may then be formed in the bottom end of
receptacle 140 and a pressurized gas from pressure source 148
released to cause a high pressure gas stream to flow through
extraction tube 144. In so doing, air is drawn into and through the
receptacle and into extraction tube 144 where the powder is
aerosolized and ejected into capture chamber 152.
[0068] Shown in FIGS. 13 and 14 is an alternative embodiment of a
receptacle 156. Receptacle 156 comprises a receptacle body 158
having a top end 160 and a bottom end 162. Receptacle body 158
forms a cavity 164 that holds a powder 166. Extending from cavity
164 is a tab 168 to facilitate handling of the receptacle. Formed
about a periphery of cavity 164 are a plurality of vents 170 that
extend through top end 160. Extending through top end 160 at a
center of cavity 164 is a hole 172 that is adapted to receive an
extraction tube (not shown) in a manner similar to that described
with previous embodiments.
[0069] Secured to top end 160 at a location above cavity 164 is a
cover 174. Cover 174 is secured to top end 160 in a manner such
that vents 170 and hole 172 is covered to seal powder 166 within
cavity 164. As shown, cavity 164 includes a raised central region
176. However, it will be appreciated that cavity 164 may be
constructed to have essentially any geometry. Cover 174 is folded
over itself and extends back over tab 168. In this way, cover 174
will generally extend outside of an aerosolization apparatus. As
such, when the user is ready to aerosolize the medicament,
receptacle 156 is inserted into the aerosolization apparatus and
cover 174 is pulled from top end 160. In this way, vents 170 and
hole 172 are exposed. An extraction tube may then be inserted
through hole 172 in a manner similar to that previously described.
By preforming vents 170 and 172, top end 160 will not need to be
pierced while within the aerosolization apparatus.
[0070] Shown schematically in FIG. 15 is an aerosolizing apparatus
200 that may be employed to aerosolize a powdered medicament using
a gas flow created by the patient's own inhalation. Apparatus 200
comprises a base 202 having a holder 204 for holding a receptacle
206, which is representative of any of the receptacles described
herein. Holder 204 includes a knob 208 to permit receptacle 206 to
be moved up and down as shown by the arrows. Also included within
base 202 is an extraction tube 210 having a bottom end 212. By
moving knob 208, extraction tube 210 may be inserted into
receptacle 206 as shown. Alternatively, extraction tube 210 may be
constructed to be movable so that it may be moved into receptacle
206. Conveniently, a piercing mechanism 214 may be positioned below
holder 204 to permit a hole to be pierced in the bottom of
receptacle 206 when knob 208 is lowered. Positioned on top of base
202 is a mouthpiece 216 over which a patient's mouth may be placed
when ready to receive a dose of medication.
[0071] In use, receptacle 206 is placed into base 202 so as to be
resting within holder 204. Knob 208 is then lowered to pierce a
hole in the bottom of receptacle 206. Knob 208 is then raised to
insert bottom end 212 of extraction tube 210 into the top of
receptacle 206 in a manner similar to that described with other
embodiments. The patient then places his or her mouth over
mouthpiece 216 and inhales. This causes air to be drawn through the
hole in the bottom of receptacle 206 and draws air through vents in
the top end of receptacle 206 in a manner similar to other
embodiments described herein. The powder drawn into extraction tube
210 then flows upward through mouthpiece 216 and into the patient's
lungs.
[0072] Optionally, extraction tube 210 may have one or more bends
218 to facilitate powder deagglomeration as the power passes
through extraction tube 210. As another option, one or more
obstacles 220 may be placed into extraction tube 210 to facilitate
powder deagglomeration. Further, it will be appreciated that bends
and obstacles may be provided in the extraction tubes of the other
aerosolization devices described herein.
[0073] The invention has now been described in detail for purposed
of clarity of understanding. However, it will be appreciated that
certain changes and modifications may be practiced within the scope
of the appended claims.
* * * * *