Self-contained heating unit and drug-supply unit employing same

• US 8,387,612 B2
• Filed: 06/16/2009
• Issued: 03/05/2013
• Est. Priority Date: 05/21/2003
• Status: Active Grant

• Current Assignee: Alexza Pharmaceuticals Inc. (Grupo Ferrer Internacional SA)
• Original Assignee: Alexza Pharmaceuticals Inc. (Grupo Ferrer Internacional SA)
• Inventors: Damani, Ramesh, Hale, Ron L., Myers, Daniel J., Quintana, Reynaldo J., Solas, Dennis W., Song, Soonho, Soni, Pravin, Tom, Curtis, Sharma, Kirshnamohan
• Primary Examiner(s): McAllister, Steven B
• Assistant Examiner(s): SAVANI, AVINASH A
• Application Number:
  US12/485,704
• Publication Number:
  US 20090301363A1
• Time in Patent Office: 1,358 Days
• Field of Search: 12626301-2631, 424/122, 424/124, 424/126, 128/203.12, 128/203.16, 128/200.14
• US Class Current: 126/263.01
• CPC Class Codes: A61M 11/00 Sprayers or atomisers specially adapted for therapeutic purposes in general B05B; aerosol containers B65D83/14
• CPC Class Codes: A61M 11/041 using heaters
• CPC Class Codes: A61M 11/042 electrical
• CPC Class Codes: A61M 11/047 by exothermic chemical reaction
• CPC Class Codes: A61M 11/048 with a flame, e.g. using a burner
• CPC Class Codes: A61M 15/06 Inhaling appliances shaped like cigars, cigarettes or pipes
• CPC Class Codes: A61M 2016/0021 with a proportional output signal, e.g. from a thermistor
• CPC Class Codes: A61M 2016/0027 pressure meter
• CPC Class Codes: A61M 2202/064 Powder
• CPC Class Codes: A61M 2205/36 related to heating or cooling
• CPC Class Codes: A61M 2205/364 by chemical reaction
• CPC Class Codes: A61M 2205/3653 by Joule effect, i.e. electric resistance
• CPC Class Codes: A61M 2205/8268 Fuel storage cells
• CPC Class Codes: B01B 1/005 Evaporation for physical or chemical purposes; Evaporation apparatus therefor, e.g. evaporation of liquids for gas phase reactions
• CPC Class Codes: B65B 29/10 Packaging two or more different substances isolated from one another in the package but capable of being mixed without opening the package, e.g. forming packages containing a resin and hardener isolated by a frangible partition
• CPC Class Codes: C06B 33/00 Compositions containing particulate metal, alloy, boron, silicon, selenium or tellurium with at least one oxygen supplying material which is either a metal oxide or a salt, organic or inorganic, capable of yielding a metal oxide
• CPC Class Codes: C06B 45/14 a layer or zone containing an inorganic explosive or an inorganic explosive or an inorganic thermic component
• CPC Class Codes: C09K 5/18 Non-reversible chemical reactions
• CPC Class Codes: F23B 2900/00003 Combustion devices specially adapted for burning metal fuels, e.g. Al or Mg
• CPC Class Codes: F23C 2900/99008 Unmixed combustion, i.e. without direct mixing of oxygen gas and fuel, but using the oxygen from a metal oxide, e.g. FeO
• CPC Class Codes: F24V 30/00 : Apparatus or devices using heat produced by exothermal chemical reactions other than combustion
• CPC Class Codes: Y02E 20/34 : Indirect CO2mitigation, i.e. by acting on non CO2directly related matters of the process, e.g. pre-heating or heat recovery

Abstract

Heating units, drug supply units and drug delivery articles capable of rapid heating are disclosed. Heating units comprising a substrate and a solid fuel capable of undergoing an exothermic metal oxidation reaction disposed within the substrate are disclosed. These heating units can be actuated by electrical resistance, by optical ignition or by percussion. Drug supply units and drug delivery articles wherein a solid fuel is configured to heat a substrate to a temperature sufficient to rapidly thermally vaporize a drug disposed thereon are also disclosed.

Claims

1. A heating unit comprising:

a) an enclosure comprising a substrate having an exterior surface and an interior surface, wherein the substrate has a thickness in the range of 0.001 to 0.020 inches;

b) a layer of solid fuel covering an area of the interior surface of the substrate corresponding to an area of the exterior surface of the substrate to be heated, wherein the solid fuel layer has a thickness in the range of 0.001 to 0.030 inches and wherein the solid fuel is configured to heat a portion of the exterior surface of the at least one substrate to a temperature of at least 200°

C. within 1 second follow ignition of the solid fuel; and

c) an igniter disposed at least partially within the enclosure for igniting the solid fuel.

2. The heating unit of claim 1 wherein within 1 second after ignition of the solid fuel, no more than 10% of said area of the exterior surface has a temperature 50°

C. to 100°

C. less than the remaining 90% of said area of the exterior surface.

3. The heating unit of claim 1, wherein within 500 milliseconds after ignition of the solid fuel, no more than 10% of said area of the exterior surface has a temperature 50°

C. to 100°

C. less than the remaining 90% of said area of the exterior surface.

4. The heating unit of claim 1, wherein within 250 milliseconds after ignition of the solid fuel, no more than 10% of said area of the exterior surface has a temperature 50°

C. to 100°

C. less than the remaining 90% of said area of the exterior surface.

5. The heating unit of claim 1, wherein the thin layer of solid fuel has a thickness in the range of 0.001 to 0.005 inches.

6. The heating unit of claim 1, wherein the enclosure comprises more than one substrate.

7. The heating unit of claim 1, wherein the substrate is a metal foil having a thickness in the range of 0.001 to 0.010 inches.

8. The heating unit of claim 1, wherein the solid fuel comprises a metal reducing agent and a metal containing oxidizing agent.

9. The heating unit of claim 8, wherein the metal containing oxidizing agent selected from at least one of the following:

MoO₃, KClO₄, KClO₃, and Fe₂O₃.

10. The heating unit of claim 8, wherein the metal reducing agent is selected from at least one of the following:

aluminum, zirconium, iron, and titanium.

11. The heating unit of claim 8, wherein the amount of metal reducing agent comprises from 60% to 90% by weight of the total dry weight of the solid fuel.

12. The heating unit of claim 8, wherein the amount of metal reducing agent comprises from 10% to 40% by weight of the total dry weight of the solid fuel.

13. The heating unit of claim 1, wherein the solid fuel comprises at least one additive material.

14. The heating unit of claim 13, wherein the additive material is selected from at least one of the following:

a clay gelling agent, nitrocellulose, polyvinylalcohol, diatomaceous earthy glass beads and a colloidal silica.

15. The heating unit of claim 7, wherein the substrate has a thickness in the range of 0.002 to 0.010 inches.

16. The heating unit of claim 7, wherein the substrate has a thickness in the range of 0.002 to 0.005 inches.

17. The heating unit of claim 1, wherein the substrate is a metal, an alloy, or a ceramic.

18. The heating unit of claim 1 wherein the igniter comprises:

an optical window in the enclosure; and

a light sensitive initiator composition disposed within the enclosure.

19. The heating unit of claim 18, where the initiator composition comprises a reducing agent and an oxidizing agent.

20. The heating unit of claim 19, wherein the reducing agent of the initiator composition is selected from at least one of the following:

zirconium, titanium, and aluminum.

21. The heating unit of claim 19, wherein the oxidizing agent of the initiator composition is selected from at least one of the following:

molybdenum trioxide, potassium perchlorate, copper oxide, and tungsten trioxide.

22. The heating unit of claim 18, wherein the initiator composition comprises aluminum, boron, molybdenum trioxide, and a clay gelling agent.

23. The heating unit of claim 1, wherein the substrate comprises a multi-layer structure.

24. The heating unit of claim 1, wherein substrate is a polyimide, a polyester, or a fluoropolymer.

25. The heating unit of claim 1, wherein the igniter is a percussive igniter.

26. The heating unit of claim 25, further comprising at least one impulse absorbing material disposed within the enclosure.

27. The heating unit of claim 25, further comprising a spacer providing an empty volume within the enclosure.

28. The heating unit of claim 1, wherein at the least one substrate is a metal, an alloy, or a ceramic.

29. The heating unit of claim 1, wherein the enclosure is capable of withstanding an internal pressure of at least 50 psig.

30. The heating unit of claim 1, further comprising a drug layer on a portion of the exterior surface of the at least one substrate.