The development of polycaprolactone (PCL) microcarriers with an emulsification module by ultrasonic spraying

The biodegradable microcarriers of polycaprolactone (PCL) have been broadly used in the embolism for treating localized tumor. Size controllability is essential in producing such microcarriers. There is difficulty in obtaining uniform particle size or lack of production efficiency with the conventional processes. In this work an ultrasonic spraying module, which is prevalent in dispensing uniform microdroplets in the coating applications, was incorporated in diffusing the PCL solution into microdroplets of fine and uniform size during the emulsion-solvent evaporation process. By carefully adjusting the production parameters, a median particle size of 50 μm with diameters ranging from 10 to 100 μm was achieved. The primary production parameters included the power supply of the spraying module, the concentration and feeding rate of the PCL solution, and the concentration and the stirring speed of the polyvinyl alcohol solution. A trial production of doxorubicin-loaded PCL microcarriers, used in breast cancer curing, was also carried out satisfactorily. The produced particle size ranged from 10 to 150 μm.