基于聚合诱导自组装制备刺激响应型纳米颗粒

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 (Figure Presented).