College of Polymer Science and Engineering, Sichuan University, Sichuan 610065, PR China; National Engineering Research Center for Biomaterials, Sichuan University, Sichuan 610065, PR China.
Colloids Surf B Biointerfaces. 2013 Dec 1;112:35-41. doi: 10.1016/j.colsurfb.2013.07.038. Epub 2013 Jul 26.
Linear and star-shape poly(ɛ-caprolactone)-b-poly(N-(3-sulfopropyl)-N-methacryloxyethyl-N,N-diethylammoniumbetaine) (L/sPCL-b-PDEAS) with 4 and 6 arms were synthesized with the combination of Ring Opening Polymerization (ROP) and Atom Transfer Radical Polymerization (ATRP). These copolymers self-assembled into micelles via solvent evaporation method. The critical micelle concentration (CMC), determined by fluorescence spectroscopy using pyrene as a probe, was lower than 10(-3)mg/mL and decreased with increasing arm numbers. Atom force microscopy (AFM) images showed that the micelles were spherical in shape with narrow size distribution. The hydrophobic drug model carotene was efficiently loaded in the polymeric micelles. The sizes and drug loading content (DLC) of the carotene-loaded micelles increased with increasing drug content in feed. In vitro drug release experiment demonstrated that the release rate of carotene from the micelles was closely related to the arm numbers and drug loading content. Linear copolymer micelles showed the fastest release rate, 4-arm star shape copolymer micelles exhibited the lowest release rate. The micelles with higher drug loading content showed lower release rate. The release kinetics of carotene from micelles fitted the Ritger-Peppas equation.
具有 4 条和 6 条支链的直链和星型聚（ε-己内酯）-b-聚（N-（3-磺丙基）-N-甲基丙烯酰氧乙基-N，N-二乙基铵甜菜碱）（L/sPCL-b-PDEAS）通过开环聚合（ROP）和原子转移自由基聚合（ATRP）的组合合成。这些共聚物通过溶剂蒸发法自组装成胶束。使用芘作为探针通过荧光光谱法测定的临界胶束浓度（CMC）低于 10(-3)mg/mL，并且随着支链数的增加而降低。原子力显微镜（AFM）图像显示，胶束呈球形，具有较窄的尺寸分布。疏水性药物模型胡萝卜素被有效地负载在聚合物胶束中。载药胶束的粒径和药物载量（DLC）随进料中药物含量的增加而增加。体外药物释放实验表明，胡萝卜素从胶束中的释放速率与支链数和药物载量密切相关。直链共聚物胶束的释放速率最快，4 臂星形共聚物胶束的释放速率最低。药物载量较高的胶束显示出较低的释放速率。胡萝卜素从胶束中的释放动力学符合 Ritger-Peppas 方程。
