Förfarande för framställning av mikropartiklar

摘要

Preparation microparticles containing a biologically active substance involves mixing a concentrated and/or solidified form of the substance with a solution of a biodegradable polymer in an organic solvent followed by solidification into microparticles. Preparation of microparticles containing biologically active substance involves: (a) preparing an aqueous solution of the active substance; (b) mixing the solution of a) with an aqueous solution of polyethylene glycol (PEG) to obtain a concentrated and/or solidified substance (a1); (c) optionally washing (a1) to obtain solution (a2); (d) mixing (a1) or (a2) a biodegradable polymer in an organic solvent to obtain a composition (a3); (e) mixing (a3) with an aqueous solution of a polymer (preferably PEG) having the ability of forming a two-phase aqueous system to form an emulsion of starch droplets containing active substance as the inner phase in an outer phase of the polymer solution (f) solidifying the starch droplets of step e) to starch microparticles (a4); (g) drying (a4); and (h) optionally applying a release controlling shell of a biocompatible and biodegradable polymer to the dried starch microparticles.