Preparation of functional nanocapsules with polylactide marosurfactant

首先，在2-乙基己酸亚锡催化剂的作用下，合成了聚环氧乙烷单油酸- d -l -丙交酯（MOPEO-PLA）。两亲性MOPEO-PLA可以利用表面活性剂的性质和活性双键来控制聚合物纳米胶囊的各种特性、表面和内部结构、表面形态、释放性能等。此外，MOPEO- pla -甲苯/水体系的界面张力测试表明，MOPEO- pla具有与MOPEO相当的表面活性。采用水层溶剂浇铸法制备MOPEO-PLA/PLA共混膜。接触角测定证实了亲水性PEO段对油水界面的选择性积累。其次，利用合成的MOPEO-PLA在油相中自组装，尝试了蛋白质的包封，有效地提取了蛋白质。随着MOPEO-PLA浓度的增加，氯仿相中水分含量急剧增加，表明MOPEO-PLA微乳液形成了大量的水分子。当水相pH接近细胞色素c的p/时，MOPEO-PLA微乳相中细胞色素c的提取量最大，温度越高，提取性能越好。从这些结果可以看出，MOPEO-PLA与细胞色素c的疏水相互作用是提取细胞色素c的主要因素。该MOPEO-PLA微乳液为蛋白质的良性提取提供了条件。MOPEO-PLA微乳液系统将在可生物降解的聚合物基质中提供一种新的封装系统，用于递送蛋白质和肽。

This research was conducted to clarify the effect of process parameters which affected the release and dispersion properties of functional polylactide nanocapsulesAt first, poly(ethyleneoxide monooleate-block-D, L-lactide) (MOPEO-PLA) was synthesized in the presence of stannous 2-ethylhexanoate catalyst. Amphiphilic MOPEO-PLA would have potential to control of various characteristics of polymer nanocapsules, surface and internal structure, surface morphology, release property and so on, by utilizing the surfactant property and the reactive double bond. Furthermore, the interfacial tension measurement of MOPEO-PLA-toluene/water system revealed that MOPEO-PLA had a good surface activity which was almost equal to that of MOPEO. The MOPEO-PLA/PLA blend films were prepared by solvent-cast on water layer. It was confirmed from contact angle measurement that the hydrophilic PEO segments were selectivity accumulated to the oil-water interface.Secondly, protein encapsulation was tried and proteins were effectively extracted by using self-assembly of synthesized MOPEO-PLA in the oil phase. The water content in the chloroform phase dramatically increased with the MOPEO-PLA concentration, indicating that a MOPEO-PLA microemulsion was formed with a large amount of water molecules. The largest amount of cytochrome c in the MOPEO-PLA microemulsion phase was extracted when the pH of the aqueous phase was close to p/ of cytochrome c, and the extraction performance increased at higher temperatures. From these results, the main factor for the extraction of cytochrome c was found to be the hydrophobic interaction between MOPEO-PLA and cytochrome c. This MOPEO-PLA microemulsion provides a benign extraction process for proteins. A MOPEO-PLA microemulsion system would enable a new encapsulation system in a biodegradable polymer matrix for delivery of proteins and peptides.