Preparation of cross-linked sodium alginate microparticles using glutaraldehyde in methanol

Polymeric sodium alginate microparticles were prepared by precipitating sod ium alginate in methanol, followed by cross-linking with glutaraldehyde. Th e extent of cross-linking was controlled by the time of exposure to glutara ldehyde. The topology of microparticles was characterized by scanning elect ron microscopy (SEM), which indicated smooth surfaces. The equilibrium swel ling experiments were carried out in water to observe the effect of cross-l inking and drug loading for better utility of microparticles. It was found that swelling decreased, but drug loading increased, with an increase in cr oss-linking of the matrix.