Preparation of VE Microcapsules and Its Controlled Release Characteristics

Abstract

Monodisperse polystyrene(PS) microcapsules containing vitamin E(VE) were prepared by membrane emulsification-dying in liquid technique. The diameter of microcapsules was about 4 times the size of the pore diameter of Shirasu porous glass (SPG) membrane, and the coefficient of variation (CV) of the microcapsule size was less than 0.2, showing a good monodispersity. Furthermore, the effects of the ratio of PS to VE ( m/m) and the diameter of microcapsules on the release characteristics were investigated. When the ratio of PS to VE ( m/m) is 40/1, the permeability coefficients were 0.71 x 10(-9) and 0.74 x 10(-9) m (.) s(-1) corresponding to the microcapsule diameters of 21.32 and 11.45 mum, and the concentrations of VE released were 8 and 12 mg (.) L-1 respectively, which conform to the optimal concentration in applications.