Polymer Bulletin

, Volume 74, Issue 11, pp 4525–4536 | Cite as

Synthesis of amphiphilic fluorescent copolymers with smart pH sensitivity via RAFT polymerization and their application in cell imaging

  • Zengfang HuangEmail author
  • Xiqi Zhang
  • Xiaoyong Zhang
  • Shiqi Wang
  • Bin Yang
  • Ke Wang
  • Jinying Yuan
  • Lei TaoEmail author
  • Yen WeiEmail author
Original Paper


In this paper, a fluorescein methacryloyl monomer (named Flu-MA) was firstly fabricated by the esterification reaction of fluorescein and methacryloyl chloride; subsequently, a novel amphiphilic fluorescent copolymer (Flu-PEG) with smart pH sensitivity was successfully prepared by RAFT copolymerizing of Flu-MA and poly(ethylene glycol) monomethacrylate (PEGMA). The result of 1H NMR and FTIR implied that both Flu-MA and PEGMA monomers were successfully incorporated into Flu-PEG copolymers, the molecular weight (M n) of which was about 39,800 with polydispersity index (PDI) as about 1.30. In aqueous solution, Flu-PEG copolymers could self-assemble into fluorescent organic nanoparticles (FONs) with about 200 nm diameters due to high water dispersibility and good fluorescence, respectively, endowed by PEGMA and Flu-MA, the fluorescence intensity of which was high sensitive to pH value of solution. More importantly, due to their high water dispersibility, excellent biocompatibility and good fluorescence, the as-prepared Flu-PEG FONs were high attractive for the application in cell imaging.

Graphical abstract

A novel amphiphilic fluorescent copolymer (Flu-PEG) with smart pH-sensitivity was successfully fabricated by RAFT copolymerizing of Flu-MA and PEGMA, which showed high water dispersibility, uniform size and excellent biocompatibility, making them be highly potential for bioimaging application.


RAFT polymerization pH Sensitivity Cell imaging Amphiphilic fluorescent copolymers 



This research was financially supported by the National Science Foundation of China (Nos. 21474057, 21104039, 21134004, 51363016), the National 973 Project (Nos. 2011CB935700), and the Science and Technology Project of Zhongshan City of China (2014A2FC309).


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Copyright information

© Springer-Verlag Berlin Heidelberg 2017

Authors and Affiliations

  1. 1.College of Chemistry and Biology, Zhongshan InstituteUniversity of Electronic Science and Technology of ChinaZhongshanPeople’s Republic of China
  2. 2.Department of Chemistry, The Tsinghua Center for Frontier Polymer ResearchTsinghua UniversityBeijingPeople’s Republic of China
  3. 3.Laboratory of Bio-Inspired Smart Interface Science, Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijingPeople’s Republic of China

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