Amphiphilic fluorescent copolymers via one-pot combination of chemoenzymatic transesterification and RAFT polymerization: synthesis, self-assembly and cell imaging

• Published in: Polymer chemistry Vol. 6; no. 4; pp. 67 - 612
• Main Authors: Huang, Zengfang, Zhang, Xiqi, Zhang, Xiaoyong, Fu, Changkui, Wang, Ke, Yuan, Jinying, Tao, Lei, Wei, Yen
• Format: Journal Article
• Language: English
• Published: 01.01.2015
• ISSN: 1759-9954; 1759-9962
• DOI: 10.1039/c4py01421a

The development of fluorescent organic nanoparticles (FONs) based on aggregation induced emission (AIE) dyes has attracted significant research interest in recent years. In this work, a novel one-pot strategy for the fabrication of AIE-based FONs was developed via a combination of RAFT polymerization and enzymatic transesterification for the first time. During this procedure, a hydrophobic tetraphenylethene-functionalized AIE dye (denoted as TPEOH) with a hydroxyl end functional group and a hydrophilic polyethylene glycol monomethyl ether (mPEG-OH, M n = 350) were simultaneously attached onto the methacrylate monomer via enzymatic transesterification. The amphiphilic copolymer formed after RAFT polymerization of the functionalized methacrylate monomers tended to self-assemble into FONs with the hydrophobic AIE core covered by a hydrophilic PEG shell. The molar fractions of TPE and PEG in the polymer were about 30.5% and 69.5%, respectively, while M n was 4700 g mol −1 with a narrow polydispersity index (PDI) (∼1.30). The obtained amphiphilic polymer nanoparticles (denoted as TPE-PEG) demonstrated good fluorescence performance and excellent dispersibility in aqueous solution. More importantly, these FONs possessed a spherical morphology with a uniform size (about 200 nm) and excellent biocompatibility, making them promising for bioimaging applications. A novel one-pot strategy for the fabrication of AIE-based FONs has been developed via a combination of RAFT polymerization and enzymatic transesterification.