The membrane emulsification method was adopted to prepare monodisperse polystyrene(PS) microspheres. Stable uniform-sized emulsion droplets were successfully obtained by pressing PS solution through the Shirasu Porous Glass(SPG) membrane into water solution containing emulsifiers at appropriate applied pressures. Monodisperse PS microspheres with size in the range of 2-20 μm were prepared by drying in liquid. The size of PS microspheres was strongly dependent on the pore size of SPG membrane and the concentration of PS solution. The size of the PS microspheres increased with the increase in the pore size of SPG membrane and the concentration of PS.
Microcapsules (or microspheres) with small size and narrow size distribution have potential applications as carriers of proteins and polypeptides. However the conventional preparation methods severely limit their real applications. Membrane emulsification technology may become a new preparation method of microcapsules with monodisperse droplets, mild conditions, good stability, low energy consumption and easy to realize mass production. In this paper, studies on membrane emulsification systems and the possible existing problems are summarized, and primary attempts on preparing alginate/chitosan microcapsules are conducted.
Liu Xiudong, Liu Qun, He Yang, Xiong Ying, Fu Yingli, Ma Xiaojun and Yuan Quan (Lab. of biomedical material engineering, Dalian Institute of Chemical Physics, CAS 116023)
