A facile strategy for fabrication of aggregation-induced emission (AIE) active fluorescent polymeric nanoparticles (FPNs) via post modification of synthetic polymers and their cell imaging

Aggregation-induced emission (AIE) active fluorescent polymeric nanoparticles (FPNs) have recently emerged as the promising nanoprobes for biological imaging for their intensive fluorescence, good photostability, desirable biocompatibility and well designability of structure and optical properties. Herein, we proposed a novel strategy for fabrication of AIE-active FPNs through the post modification of synthetic copolymers to form Schiff base. The size, morphology, optical properties and biocompatibility as well as cell uptake behavior were evaluated in detailed. To fabricate these AIE-active FPNs, poly(PEG- co -VA) copolymers were first obtained via addition-fragmentation chain transfer polymerization using poly(ethylene glycol) methyl ether methacrylate (PEGMA) and 3-vinylaniline (VA) as the monomers. Then the AIE-active SA-poly(PEG- co -VA) FPNs were formed through the reaction between salicylaldehyde (SA) and VA. Results demonstrated that SA-poly(PEG- co -VA) FPNs possess bright fluorescence, superior photo-bleaching resistance, excellent biocompatibility and efficient cell uptake behavior. To the best of our knowledge, this is the first report for fabrication AIE-active FPNs through post modification of synthetic copolymers. The facile fabrication procedure and the remarkable features suggested that these AIE-active FPNs promising candidates for biomedical applications.