Patent ID: 8198354

Claim:
A method of manufacturing a metered dose inhaler (MDI), said method comprising: contacting an elastomeric gasket material comprising acrylonitrile butadiene rubber and one or more extractable compounds including oleic acid, with a solution comprising a lower alcohol, wherein the solution is at a temperature of at least 40° C. to extract oleic acid from the elastomeric gasket material such that the gasket material comprises between about 0.04 and 0.17% oleic acid to form a MDI sealing gasket; agitating the elastomeric gasket material and the solution, wherein the agitating of the elastomeric gasket material is performed subsequent to the contacting of the elastomeric gasket material with the solution; providing other MDI components and a pharmaceutical aerosol formulation comprising salmeterol xianfoate and fluticasone propionate; and assembling the MDI.