Self-contained heating unit and drug-supply unit employing same
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.
1. A drug supply unit comprising:
a heating unit comprising:
an enclosure comprising a substrate having an exterior surface and an interior surface; and
a solid fuel comprising a metal, which metal is a reducing agent, and a metal-containing oxidizing agent, wherein the solid fuel is disposed on the interior surface of the substrate as a layer, wherein the thickness of the layer is in the range 0.001 inches to 0.030 inches and
a drug disposed on a portion of the exterior surface of the substrate;
wherein said drug comprises a film and the film has a thickness of less than 20 μm.
2. The drug supply unit of claim 1 , wherein the drug supply unit comprises more than one heating unit.
3. A drug delivery device comprising:
a housing defining an airway;
a heating unit comprising:
an enclosure comprising a substrate having an exterior surface and an interior surface; and a solid fuel comprising a metal, which metal is a reducing agent, and a metal-containing oxidizing agent, wherein the solid fuel is disposed on the interior surface of the substrate as a layer, wherein the thickness of the layer is in the range 0.001 inches to 0.030 inches; and
a drug disposed on a portion of the exterior surface of the substrate, wherein the portion of the exterior surface comprising the drug is configured to be disposed within the airway; and
an igniter comprising an initiator composition configured to ignite the solid fuel;
wherein said igniter comprises a resistive heating element and an initiator composition disposed on the resistive heating element.
4. The drug delivery device of claim 3 , wherein the initiator composition comprises at least one metal which is a reducing agent and at least one oxidizing agent.
5. The drug delivery device of claim 4 , wherein the metal which is a reducing agent of the initiator composition is selected from at least one of: aluminum and zirconium.
6. The drug delivery device of claim 3 , wherein the oxidizing agent of the initiator composition is selected from a chlorate of an alkali metal, a chlorate of an alkaline earth metal, a perchlorate of an alkali metal, and a perchlorate of an alkaline earth metal.
7. The drug delivery device of claim 6 , wherein the oxidizing agent is selected from potassium chlorate and potassium perchlorate.
8. The drug delivery device of claim 3 , wherein the initiator composition comprises an additive material.
9. The drug delivery device of claim 8 wherein the additive material is selected from diatomaceous earth, glass beads, and colloidal silica.
10. The drug delivery device of claim 3 , further comprising a mechanism for producing an electric current to activate the igniter.
11. The drug delivery device of claim 3 , further comprising a mechanism for producing electromagnetic radiation to activate the igniter.
12. The drug delivery device of claim 3 , further comprising a mechanism for producing a percussive force to activate the igniter.
13. The drug delivery device of claim 3 , wherein the drug delivery device comprises more than one heating unit.