Synthesis and biological imaging of fluorescent polymeric nanoparticles with AIE feature via the combination of RAFT polymerization and post-polymerization modification

• Published in: Dyes and pigments 2018-11, Vol.158, p.79-87
• Main Authors: Liu, Yanzhu, Mao, Liucheng, Yang, Saijiao, Liu, Meiying, Huang, Hongye, Wen, Yuanqing, Deng, Fengjie, Li, Yongxiu, Zhang, Xiaoyong, Wei, Yen
• Format: Article
• Language: English
• Subjects: Aggregation-induced emission; Biological imaging; Fluorescent polymeric nanoparticles; Post-polymerization
• ISSN: 0143-7208; 1873-3743
• DOI: 10.1016/j.dyepig.2018.05.032

In recent years, florescent polymeric nanoparticles (FPNs) containing aggregation-induced emission (AIE) fluorogens have received great intention for their potential applications in biological imaging and theranostic nanomedicine. Herein, we have developed AIE-active FPNs through a combination of reversible addition-fragmentation chain transfer (RAFT) polymerization and post-polymerization modification strategies. The salicylaldehyde (SA) containing zwitterionic copolymers are fabricated via RAFT polymerization and further modified by benzophenone hydrazone (BPH) via Schiff base reaction. The obtained AIE-active amphiphilic copolymers BPH-poly(FHMA-co-MPC) can self-assemble in aqueous solution with the hydrophobic fluorogens aggregating together to form the core and the hydrophilic chains to form the protective shell. BPH-poly(FHMA-co-MPC) and the resulting FPNs are characterized by 1H nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, transmission electron microscopy and fluorescence spectroscopy. Results demonstrate that BPH-poly(FHMA-co-MPC) are successfully synthesized and as-prepared BPH-poly(FHMA-co-MPC) FPNs exhibit desirable morphology and size, good dispersibility, high brightness, remarkable photostability and large Stokes shifts. More importantly, through cytotoxicity test and cell uptake behavior, these BPH-poly(FHMA-co-MPC) FPNs show low toxicity and excellent cell dyeing behavior. Taken together, we have developed a facile and effective method for the fabrication of AIE-active FPNs, which display great potential for biomedical applications. A novel strategy based on the combination of RAFT polymerization and post-polymerization has been developed for the synthesis of fluorescent polymeric nanoparticles with ESIPT feature. [Display omitted] •Fluorescent polymeric nanoparticles with aggregation-induced emission feature.•AIE-active FPNs through formation of Schiff base.•The method for preparation of AIE-active FPNs is rather simple and effective.•These AIE-active FPNs are promising for biomedical applications.