基于聚合诱导自组装制备刺激响应型纳米颗粒

Stimuli Responsive Nano-objects via Polymerization Induced Self-assembly

环境敏感的刺激响应型嵌段共聚物纳米颗粒能在一定条件下发生形貌与尺寸的转变,在药物递送等领域具有重要的应用价值.近年来,聚合诱导自组装(PISA)制备纳米颗粒技术蓬勃发展,相较于传统透析等方法,可以快速高效(分钟-小时)制备得到不同形貌的高固含量(10 wt%~50 wt%)纳米颗粒.本文总结了基于聚合诱导自组装制备刺激响应型纳米颗粒的研究进展,分析了通过引入特定基团实现对动态共价键、酶、pH、CO_(2)、氧化还原、热、光等外界条件响应的策略,探讨了刺激响应前后纳米颗粒形貌与尺寸的转化及其在生物医学领域的应用,提出了相关领域存在的机遇与挑战.

Stimuli responsive block copolymer nano-objects enable morphology and/or size transformations under certain conditions,which are widely used in biomedical applications.The nano-objects are traditionally prepared via dialysis method of amphiphilic block copolymers,however,suffering from long time(>day)and low solid content(<1 wt%).Recently,polymerization induced self-assembly(PISA)has emerged as a rapid(~hours or less)synthetic strategy to nano-objects with high solid contents(10 wt%-50 wt%)and diverse morphologies.Among living/controlled polymerization methodologies,reversible addition fragmentation chain transfer radical polymerization(RAFT)and ring-opening metathesis polymerization(ROMP)are mostly investigated and used in PISA.This review focuses on synthesis and applications of stimuli responsive nano-objects via PISA.By introducing the specific structure into the monomers,dynamic covalent bonding,enzyme,pH,CO2,redox,thermal and light responsive nano-objects are prepared via RAFT or ROMP PISA.In response to the external stimuli,the morphology and/or size transformations are observed,which provide promising opportunities in biomedical applications,such as controlled drug release or gene delivery.Although remarkable advances have been achieved,great challenges still remain for PISA-based stimuli responsive nano-objects.Powerful polymerization approaches should be utilized in PISA,such as combing orthogonal mechanisms and microreactor-based flow chemistry.Structure design should be deeply considered to provide more efficient stimuli responsive modes.Morphologies and/or size transformation process should be carefully investigated to advance the real applications of PISA-based stimuli responsive nano-objects.