| In this essay, a series of gelatinous polysucrose (PS) microspheres with mean particle size between 200-500μm were synthesized by reversed-phase suspension polymerization, using sucrose as raw material and epichlorohydrin as crosslinker. Their chemical structure was determined by FTIR and XPS. Their appearance was observed by POM and SEM. Crosslinking density, hydroxyl content and equilibrium water content (EWC) were determined. It is found that crosslinking density increased with increase of crosslinker amount, while hydroxyl content decreased with crosslinker amount. And EWC, which was affected by hydroxyl content, also declined.Then a series of porous PS microspheres range from 330-360μm were synthesized using dimethyl ether of polyethylene glycol (DMPE) as porogen. Their crosslinking density, porosity, hydroxyl content and EWC were also investigated. It is indicated that crosslinking density dropped drastically with decrease of porogen amount. When porogen amount was below 37.5%, porosity increased with porogen amount; while above 37.5%, porosity decreased with it. Hydroxyl content increased with porogen amount. And EWC, which was influenced mostly by hydroxyl content, increased as a result.Langmuir formula was used to describe adsorption of bovine serum albumin (BSA) on PS microspheres. It is found that qm of gelatinous microspheres improved with hydroxyl content, dropped evidently with salt concentration, and declined with pH in range of 4.5-9.0. The adsorption rate of gelatinous microspheres with higher hydroxyl content was much higher than those with lower hydroxyl content. It is revealed that hydroxyl content was also the key factor to q m of porous PS microspheres. qm increased with hydroxyl content, and reached its maximum at 98.54mg/g, which was much higher than gelatinous PS microspheres. The optimum porogen amount was 37.5% (crosslinker amount is 37.5%). Adsorption capacities of both gelatinous and porous microspheres showed little descent during repeated usage (five times).
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