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小肠上皮是难溶性药物口服递送的主要屏障,本研究基于小肠上皮表达的新型有机阳离子转运体2(OCTN2),设计并制备了由肉毒碱修饰的聚(2-乙基-2-噁唑啉)-聚乳酸(Car-PEOz-PLA)与聚乙二醇-聚乳酸(mPEG-PLA)构成的聚合物胶束.用1H NMR、TLC、硫氰酸铬铵(雷氏盐)沉淀法确证了所合成的Car-PEOz-PLA的结构,用GPC测定其分子量为7260 g/mol,PDI=1.44.采用薄膜水化法制备包载香豆素6的肉毒碱修饰的聚合物胶束,其粒径约为31 nm,载药量和包封率分别为0.098％±0.03％和92.67％±2.80％.其在模拟胃液和肠液中具有相似的体外释放行为,并明显增强了难溶药物的小肠吸收.因此,靶向OCTN2的聚合物胶束在口服递送难溶药物方面具有潜在的优势.“,”The intestinal epithelium is the main barrier to the oral delivery of poorly water-soluble drugs.Based on the specific transporters expressed on the apical membrane of the intestinal epithelium,novel polymer micelles targeting to the organic cation transporter 2 (OCTN2) were constructed by combining camitine conjugated poly(2-ethyl-2-oxazoline)-poly(D,L-lactide) (Car-PEOz-PLA) with monomethoxy poly(ethylene glycol)-poly(D,L-lactide) (mPEG-PLA).The structure of the synthesized Car-PEOz-PLA was confirmed by 1H NMR,TLC and ammonium reineckate precipitation reaction,and the number-average molecular weight determined by GPC was 7260 g/mol with a low PDI of 1.44.Coumarin 6-loaded carnitine modified polymeric micelles prepared by film hydration method were characterized to have a nano-scaled size of about 31 nm in diameter,uniform spherical morphology,high drug loading content of 0.098％±0.03％ and encapsulation efficiency of 92.67％±2.80％.Moreover,the carnitine-modified micelles exhibited the similar in vitro release behavior in SGF and SIF,and evidently enhanced intestinal absorption of poorly water-soluble agent.Therefore,the designed OCTN2-targeted micelles might have a promising potential for oral delivery of poorly water-soluble drugs.