Process for preparing crystalline particles of fluticasone, beclomethasone, salmeterol and salbutamol

摘要

The present invention relates to a novel process for preparing crystalline particles of substance which comprises mixing a solution of the substance in a liquid solvent with a liquid anti-solvent for said substance, which liquid anti-solvent is miscible with the liquid solvent, characterised in that the resultant crystalline particles generated are harvested by a process which comprises: (i) mixing a first liquid phase formed from the resultant suspension of crystalline substance in solvent/anti-solvent mixture with a third liquid which is immiscible with said solvent/anti-solvent mixture or a component thereof thereby forming a second liquid phase and which is a non-solvent for the substance such that the substance is segregated into the second liquid phase; (ii) separating the two phases; and (iii) separating the crystalline particles of substance from the second liquid phase.