Hydrophilic Polyester Microspheres: Effect of Molecular Weight and Copolymer Composition on Release of BSA
Hydrophilic Polyester Microspheres: Effect of Molecular Weight and Copolymer Composition on Release of BSA
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DOI：
10.1007/s11095-010-0205-8
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发表时间：
2010-09-01
影响因子：
3.7
通讯作者：
Hennink, Wim E.
中科院分区：
文献类型：
--
作者：
Ghassemi, Amir H.;van Steenbergen, Mies J.;Hennink, Wim E.
目的研究羟基化脂肪族聚乳酸-羟基甲基乙醇酸（PLHMGA）微球对牛血清白蛋白（BSA）的释放。方法采用双乳液溶剂蒸发法制备bsa负载微球。研究了共聚物组成和分子量对体外释放和降解的影响。用荧光光谱法和粒径排除色谱法研究了释放的牛血清白蛋白的完整性。结果50%羟甲基乙醇酸（HMG）制备的PLHMGA微球呈爆发性释放，5 ~ 10 d缓释。由35%和25% HMG共聚物制备的PLHMGA微球显示，BSA的缓释率分别为80%，缓释时间为30天和60天。BSA的释放不受聚合物分子量的影响。荧光光谱和SEC表明，释放的牛血清白蛋白保持了其结构的完整性。微球完全可降解，当HMG含量从50%降低到25%时，降解时间从20天左右增加到60天。结论将降解和释放数据结合起来，可以得出PLHMGA微球释放牛血清白蛋白受微球降解控制的结论。
Purpose To study the release of a model protein, bovine serum albumin (BSA), from microspheres of an hydroxylated aliphatic polyester, poly(lactic-co-hydroxymethyl glycolic acid) (PLHMGA).Methods BSA-loaded microspheres were prepared by a double emulsion solvent evaporation method. The effect of copolymer composition and the molecular weight of the copolymer on in vitro release and degradation were studied. The integrity of the released BSA was studied by fluorescence spectroscopy and size exclusion chromatography (SEC).Results Microspheres prepared from PLHMGA with 50% hydroxymethyl glycolic acid (HMG) showed a burst release followed by a sustained release in 5-10 days. PLHMGA microspheres prepared from a copolymer with 35% and 25% HMG showed a sustained release of BSA up to 80% for 30 and 60 days, respectively. The release of BSA was hardly affected by the molecular weight of the polymer. Fluorescence spectroscopy and SEC showed that the released BSA preserved its structural integrity. Microspheres were fully degradable, and the degradation time increased from similar to 20 days to 60 days when the HMG content decreased from 50% to 25%.Conclusions Taking the degradation and release data together, it can be concluded that the release of BSA from PLHMGA microspheres is governed by degradation of the microspheres.