Preparation of AIE active and thermoresponsive poly(1-ethenyl-4-(1,2,2-triphenylethenyl)-benzene-b-N-isopropylacrylamide) micelles for cell imaging

Three diblock copolymers ( PTPEE-PNns ) with controllable polymer structures were synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization, combining 1-ethenyl-4-(1,2,2-triphenylethenyl)-benzene (TPEE) and N-isopropylacrylamide (NIPAM). All PTPEE-PNns copolymers showed remarkable aggregation-induced emission (AIE) characteristic. Due to the amphiphilic structure of the copolymers, PTPEE-PNn micelles (mainly hollow) were prepared with either “precipitation” or “dialysis” method, respectively. Scanning electron microscopy, transmission electron microscopy , dynamic light scattering and fluorescence methodology were performed to investigate the morphology, size distribution and stability of the micelles, revealing the effects of molecular weight and micelle preparation method on the nanostructure of the micelles. The PTPEE-PN2 hollow micelles prepared by the “dialysis” method had the advantages of small particle size, extremely narrow particle size distribution , remarkable thermal sensitivity, excellent particle stability, and showed good biocompatibility and fluorescence emission capability in cell imaging . This work would inspire more approaches to prepare novel AIE-active, thermoresponsive and biocompatible polymers for biomedical application .