Process for the manufacture of particles with size (sub) micron by dissolving compressed gas and surfactants.

A process for the manufacture of a pulverous preparation of a biologically active size composite (sub) chosen micra the group consisting of Saquinavir, Orlistat, Isotretinoin, Sulfamethoxazol, Diazepam, Moclobemide, and Bosentan comprising the steps of: (1) dissolving said biologically active compound under elevated pressure in compressed dimethylether containing a surface modifier selected from the group consisting of polyethylene glycol ether Write lauryl, cetyl, stearyl and what oleilalcoholes or di-isooctyl-sodium sulfosuccinate; (2a) rapidly expanding the compressed solution of aso (1) thereby precipitating the dissolved compound; or (2b) spraying the compressed solution of step (1) to form an antisolvent selected from compressed carbon dioxide or water optionally containing surface modifier selected from the group consisting of a polyethylene glycol ether of ?lauryl, acetyl, stearyl and what oleilalcoholes or di-isooctyl-sulfosuccinate, under vacuum, atmospheric pressure or elevated pressure; (3) optionally converting the antisolvant phase of step (2b) into a pulverous preparation using conventional powder processing techniques.