Polymeric Temperature and pH Fluorescent Sensor Synthesized by Reversible Addition-Fragmentation Chain Transfer Polymerization

Simple-structured copolymer, poly(NIPMAM-co-CPMA), consisting of N-isopropylmethacrylamide (NIPMAM) and (Z)-4-(1-cyano-2-(4-(dimethylamino) phenyl)vinyl)phenyl-methylacrylate (CPMA) units as thermo- and pH-responsive fluorescent signaling parts, respectively, has been synthesized by reversible addition-fragmentation chain transfer polymerization. The copolymer PCN250 (m/n = 250) shows absorbance enhancement or decrease at different pH value. However, the fluorescence intensity of this copolymer shows enhancement with a rise in temperature regardless of pH value in the range of pH 4-10. In addition, fluorescence suppression of copolymer (PCN250) was observed with high proton concentration. Moreover, the lower critical solution temperature of the copolymers, poly-(NIPMAM-co-CPMA), with different component was also investigated. (C) 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 50: 2219-2226, 2012