TY - JOUR
T1 - Ultrasensitive ratiometric fluorescent pH and temperature probes constructed from dye-labeled thermoresponsive double hydrophilic block copolymers
AU - Hu, Jinming
AU - Zhang, Xiaozheng
AU - Wang, Di
AU - Hu, Xianglong
AU - Liu, Tao
AU - Zhang, Guoying
AU - Liu, Shiyong
PY - 2011
Y1 - 2011
N2 - We report on the fabrication of highly sensitive ratiometric fluorescent pH and temperature probes based on thermoresponsive double hydrophilic block copolymers (DHBCs) with the two blocks labeled with two types of dyes possessing different pH-switchable emission characteristics. P(NIPAM-co-FITC)-b-P(OEGMA- co-RhBAM) DHBCs were synthesized via consecutive reversible addition- fragmentation chain transfer (RAFT) polymerizations in combination with post-modifications, where NIPAM, OEGMA, FITC, and RhBAM are N- isopropylacrylamide, oligo(ethylene glycol) monomethyl ether methacrylate, fluorescein isothiocyanate, and rhodamine B-based derivatives, respectively. Due to that FITC and RhBAM moieties exhibit prominent decrease and increase in emission intensities with decreasing solution pH, respectively, intensity ratios of characteristic RhBAM and FITC emission bands, I582/I 522, of P(NIPAM-co-FITC)-b-P(OEGMA-co-RhBAM) unimers at 25 ?C exhibit 39-fold changes in the range of pH 2-10. At elevated temperatures, thermo-induced formation of PNIPAM-core micelles enables effective fluorescence resonance energy transfer (FRET) between FITC and RhBAM moieties respectively located within micellar cores and coronas, and I582/I522 exhibits 52.5-fold changes in the same pH range. The reported dually modulated multicolor-emitting P(NIPAM-co-FITC)-b-P(OEGMA-co-RhBAM) DHBCs are capable of ultrasensitive fluorometric detection of solution pH and temperature in a ratiometric manner, which augurs well for their practical applications in sensing, imaging, and the fabrication of new generation of theranostic systems.
AB - We report on the fabrication of highly sensitive ratiometric fluorescent pH and temperature probes based on thermoresponsive double hydrophilic block copolymers (DHBCs) with the two blocks labeled with two types of dyes possessing different pH-switchable emission characteristics. P(NIPAM-co-FITC)-b-P(OEGMA- co-RhBAM) DHBCs were synthesized via consecutive reversible addition- fragmentation chain transfer (RAFT) polymerizations in combination with post-modifications, where NIPAM, OEGMA, FITC, and RhBAM are N- isopropylacrylamide, oligo(ethylene glycol) monomethyl ether methacrylate, fluorescein isothiocyanate, and rhodamine B-based derivatives, respectively. Due to that FITC and RhBAM moieties exhibit prominent decrease and increase in emission intensities with decreasing solution pH, respectively, intensity ratios of characteristic RhBAM and FITC emission bands, I582/I 522, of P(NIPAM-co-FITC)-b-P(OEGMA-co-RhBAM) unimers at 25 ?C exhibit 39-fold changes in the range of pH 2-10. At elevated temperatures, thermo-induced formation of PNIPAM-core micelles enables effective fluorescence resonance energy transfer (FRET) between FITC and RhBAM moieties respectively located within micellar cores and coronas, and I582/I522 exhibits 52.5-fold changes in the same pH range. The reported dually modulated multicolor-emitting P(NIPAM-co-FITC)-b-P(OEGMA-co-RhBAM) DHBCs are capable of ultrasensitive fluorometric detection of solution pH and temperature in a ratiometric manner, which augurs well for their practical applications in sensing, imaging, and the fabrication of new generation of theranostic systems.
UR - http://pubs.rsc.org.ezproxy.lib.monash.edu.au/en/content/articlepdf/2011/jm/c1jm13575a
U2 - 10.1039/c1jm13575a
DO - 10.1039/c1jm13575a
M3 - Article
SN - 0959-9428
VL - 21
SP - 19030
EP - 19038
JO - Journal of Materials Chemistry
JF - Journal of Materials Chemistry
IS - 47
ER -