中文摘要：

长循环纳米粒子的亲水壳层虽能有效延长纳米粒子在体内的循环时间,但到达靶向部位后壳层会大大制约其与细胞膜的作用,并延缓药物的释放。壳层可脱落纳米粒子可很好地解决长循环纳米粒子壳层这一问题,提高药物的生物利用度,其设计与制备具有很大的研究意义。本文介绍了不同类型的壳层可脱落纳米粒子,包括pH敏感型、氧化还原敏感型、酶解型等,着重阐述了壳层可脱落纳米粒子的设计机理和应用优势,并综述了国内外生物医用类壳层可脱落纳米粒子的研究进展与发展方向。

英文摘要：

The development of new intelligent drug carrier is one of the most critical challenges in cancer treatment.Nano-vehicles such as liposomes,polymeric micelles and lipoplexes are extensively investigated for this purpose.For successful drug delivery,one prerequisite is the long circulating time in vivo.Nanoparticles which used hydrophilic polymers as the＂stealth＂coating materials can prolong the circulating time via preventing the vehicles from the clearance by blood proteins and being uptaken by macrophages.However,hydrophilic coatings of nanoparticles may hamper the drug release and interaction with target cell after localizing at the pathological site,limiting the therapeutic effect.Presently,this dilemma could be circumvented by the development of the sheddable nanoparticles.Sheddable nanoparticles,which are capable of shedding their ＂outer layers＂ when needed,may facilitate the drug release as well as the interaction with the target cell.Herein,we present an overview of the recent work on sheddable nanoparticles with different＂shedding＂mechanisms,including pH-sensitivity,redox sensitivity and enzyme digestion,with an emphasis on their designs and biomedical applications.In addition,recent advances and perspectives of the sheddable nanoparticles are included.