Delivery of aerosols containing small particles through an inhalation route

Abstract

The present invention relates to the inhalation delivery of aerosols containing small particles. Specifically, it relates to the delivery of drug containing aerosols having particles with a mass median aerodynamic diameter less than 1μ for inhalation therapy. In an aspect of the present invention the drug containing aerosol comprises particles having a mass median aerodynamic diameter between 10 nm and 1μ. Preferably, the particles have a mass median aerodynamic diameter between 10 nm and 900 nm. More preferably, the particles have a mass median aerodynamic diameter between 10 nm and 800 nm, 10 nm and 700 nm, 10 nm and 600 nm, 10 nm and 500 nm, 10 nm and 400 nm, 10 nm and 300 nm, 10 nm and 200 nm, or 10 nm and 100 nm.

1 . A method for preparing an aerosol of particles having a mass median aerodynamic diameter of less than 1 μm comprising the steps of 
 a) depositing a compound composition on a substrate  
 b) heating said substrate to form a vapor of at least a portion of the composition  
 c) mixing the resulting vapor with a gas, in a ratio to form an aerosol with a mass median aerodynamic diameter of less than 1 μm when a stable number concentration of particles in the gas is reached.  
 
     
     
         2 . The method of  claim 1 , wherein said mixing involves passing a gas across the surface of said composition during heating.  
     
     
         3 . The method of  claim 1 , wherein said mixing involves passing a gas with turbulence across the surface of said composition during heating.  
     
     
         4 . The method of  claim 3 , wherein said gas is air.  
     
     
         5 . The method of  claim 1 , wherein the composition is deposited as a thin film.  
     
     
         6 . Method of  claim 5 , wherein the thin film is of a thickness of less than 10 microns.  
     
     
         7 . The method of  claim 6 , wherein the thin film is vaporized at a rate of 0.5 to 2 mg/sec.  
     
     
         8 . The method of  claim 1 , wherein said mass median aerodynamic diameter is between 10 nm and 900 nm.  
     
     
         9 . The method of  claim 1 , wherein said mass median aerodynamic diameter is between 10 nm and 500 nm.  
     
     
         10 . The method of  claim 1 , wherein said mass median aerodynamic diameter is between 10 nm and 100 nm  
     
     
         11 . The method of  claim 1 , wherein said vaporization is complete in less than 2 seconds.  
     
     
         12 . The method of  claim 1 , wherein said heating is at a rate of at least 1000° C./second.  
     
     
         13 . The method of  claim 1 , wherein the substrate is metallic.  
     
     
         14 . The method of  claim 13 , wherein the metallic substrate is stainless steel.  
     
     
         15 . The method of  claim 1 , wherein said heating is resistive or inductive.  
     
     
         16 . The method of  claim 1 , wherein the mass median aerodynamic diameter has a geometric standard deviation of less than 2.  
     
     
         17 . The method of  claim 1 , wherein the stable number concentration of particles in the gas is about 10 9  particles/mL.