Formulation and Evaluation of Novel Starch-based Microspheres for Adsorption of Ascorbic Acid

摘要

The microspheres (SBM) was prepared using N,N'-methylene-bis-acrylamide (MBAA) as cross-linker and K_2S_2O_8-Na_2SO_3 as initiator in water-in-oil emulsion. And then the effects of the O/W ratio (v/v), the amount of cross-linker and the amount of K_2S_2O_8-Na_2SO_3 on particle size and swelling ratio were investigated. An increase in particle size was observed by increasing the amount of cross-linker and the amount of K_2S_2O_8-Na_2SO_3, while with decreasing the O/W ratio and the amount of K_2S_2O_8-Na_2SO_3 particle size was found to decreased, which was just opposite to the trend of swelling ratio. Particle size of the microspheres is 12-65μm. Ascorbic acid was selected as a sample drug, and the function between ascorbic acid and SBM was illustrated by the three-electrode equipment. The absorption mechanism suggested that the absorption of ascorbic acid on SBM is exist and ascribes to hydrogen bond for -OH and -NH_2 of SBM and -OH of ascorbic acid.