Department of Nursing, I-Shou University, Kaohsiung 82445, Taiwan, ROC.
Colloids Surf B Biointerfaces. 2012 Jan 1;89:271-6. doi: 10.1016/j.colsurfb.2011.09.032. Epub 2011 Sep 22.
In this investigation, biodegradable polymer poly(L-lactic acid) (PLA) microspheres were prepared by the W(1)/O/W(2) solvent evaporation method. The inner phase was aqueous solution (W(1)) that contained bovine serum albumin that was labeled with fluorescein isothiocyanate (FITC-BSA). PLA was dissolved in chloroform with emulsifier sorbitan monooleate (span 80) as the dispersed phase (O). These two solutions (W(1)/O) were emulsified by a homogenizer to form a primary emulsion. Polyvinyl alcohol (PVA) used as surfactant, was applied in the formation of microspheres (W(2)). 0.5% (w/v) PLA was stirred at 3000 rpm using a homogenizer. Microspheres with sizes of up to around 10 μm were produced. These microspheres were separated by the glycerol gradient method, and take microspheres at part of 25% glycerol gradient concentration was analyzed by flow cytometry, indicating a more homogeneous particle size distribution than that not separated. The microspheres were degraded using several enzymes, and around 40% was degraded by 72 h. This result reveals the effectiveness of drug delivery by PLA microspheres, which was evaluated by performing a drug release test and flow cytometric analysis. The FITC-BSA concentration in the supernatant increased with the experimental time. At the phagocytosis experiments, encapsulated with FITC-BSA drug of microspheres can be used by the cell, as particle size approximately 1 μm.
在这项研究中，采用 W(1)/O/W(2)溶剂蒸发法制备了可生物降解的聚合物聚（L-乳酸）（PLA）微球。内相为含有荧光素异硫氰酸酯（FITC-BSA）标记的牛血清白蛋白的水溶液（W(1)）。PLA 溶解在氯仿中，乳化剂山梨醇单油酸酯（span 80）作为分散相（O）。这两种溶液（W(1)/O）通过匀浆器乳化形成初级乳液。聚乙烯醇（PVA）用作微球形成的表面活性剂（W(2)）。0.5%（w/v）的 PLA 在 3000 rpm 的搅拌速度下使用匀浆器进行搅拌。可产生最大粒径约为 10 μm 的微球。这些微球通过甘油梯度法进行分离，并通过流式细胞术分析 25%甘油梯度浓度部分的微球，表明粒径分布更为均匀。微球用几种酶进行降解，72 小时后约有 40%被降解。通过进行药物释放试验和流式细胞术分析评估 PLA 微球的药物递送效果，这一结果表明了 PLA 微球的有效性。在吞噬实验中，载有 FITC-BSA 药物的微球可被细胞摄取，粒径约为 1 μm。
