Preparation and protein adsorption of porous dextran microspheres

In present work, porous dextran microspheres with good morphology were synthesized by reversed-phase suspension polymerization. Dextran was used as raw material, epichlorohydrin (ECH) as crosslinker, and dimethyl ether of polyethylene glycol (DMPE) as porogen. And porous dextran microspheres were prepared by freezing–drying method. The morphology of the porous dextran microspheres was characterized by the scanning electronic microscope (SEM). The dry and hydrated densities, average pore volume, porosity, hydroxyl content and equilibrium water content were measured. Micropore structure was found on the dextran microspheres. With the increase of porogen amount, the dry density decreased, the hydrated density, the average pore volume, porosity and equilibrium water content initially increased and then decreased, while the hydroxyl content increased. Bovine serum albumin (BSA) was used as an adsorbate model to examine the adsorption behavior of the porous microspheres. The saturated adsorption capacities of these microspheres ranged from 59.1 mg/g to 138.9 mg/g while the amount of porogen increased from 10% to 50%.