CAJ | 학술논문

通过大分子引发开环聚合和侧基改性,制备了一种侧链含有吗啉丙基的聚乙二醇-聚（吗啉丙基-天冬酰胺）-聚丙氨酸三嵌段共聚物。利用肿瘤细胞外、细胞内和正常组织pH值环境的差异,调节聚合物载药纳米粒子的结构和性能实现肿瘤部位靶向释放的目的。在水溶液中,此聚合物可自组装形成一种核-壳-冠型的3层共聚物胶束,其中疏水性的聚丙氨酸链段自聚集形成胶束的核,聚（吗啉丙基-天冬酰胺）链段形成具有pH值-响应性的壳层,用于包埋和释放药物,外围的聚乙二醇链段可以提供一个稳定的水合冠层,延长药物的体内循环时间。以阿霉素作为模型药物在自组装的过程中包埋到胶束内。研究发现,由于吗啉环在酸性条件下的质子化导致链段亲疏水性质发生明显变化,载药胶束的药物释放能力随环境pH值的降低药物的释放速率显著增加。
통과대분자인발개배취합화측기개성,제비료일충측련함유마람병기적취을이순-취（마람병기-천동선알）-취병안산삼감단공취물。이용종류세포외、세포내화정상조직pH치배경적차이,조절취합물재약납미입자적결구화성능실현종류부위파향석방적목적。재수용액중,차취합물가자조장형성일충핵-각-관형적3층공취물효속,기중소수성적취병안산련단자취집형성효속적핵,취（마람병기-천동선알）련단형성구유pH치-향응성적각층,용우포매화석방약물,외위적취을이순련단가이제공일개은정적수합관층,연장약물적체내순배시간。이아매소작위모형약물재자조장적과정중포매도효속내。연구발현,유우마람배재산성조건하적질자화도치련단친소수성질발생명현변화,재약효속적약물석방능력수배경pH치적강저약물적석방속솔현저증가。
A novel biodegradable ABC type triblock copolymer mPEG-poly（benzyl L-aspartate）-P（L-Alanine） was synthesized by N-carboxyl anhydride ring-opening polymerization.Morpholine groups were tethered to the side chains of poly（L-asparagine） segments by aminolysis.mPEG-poly（morpholine propyl-asparagine）-poly（L-alanine） nanoparticles were prepared and used as carriers for tumor-targeting drug delivery.Doxorubicin（DOX） was encapsulated in the nanoparticles to explore the release profile.These DOX-loaded polymeric micelles exhibited rapid release of DOX from the micelles in weakly acidic environments but very slow release under physiological conditions（pH 7.4）.This is most likely due to protonation and a change in hydrophilicity of the morpholine groups in the poly（L-asparagine）.This new approach may serve as a promising platform to formulate targeted drug delivery systems.