| 초록 |
Molecular sensors capable of detecting environmental pH have been sought for probing biological phenomena in living cells. The primary objective of this study is to development a new biocompatible polymeric sensor which shows a robust on-and-off pH sensitive characteristic in the efficiency of fluorescence resonance energy transfer (FRET). As a pH sensitive moiety, sulfadimethoxine monomer (SDM) is chosen and polymerized via ATRP. As a FRET donor and acceptor, PEGylated 7-acetoxy-4-bromomethyl coumarin (PabC) and coumarin 343 (C343) are selected and located at both ends of the polymeric backbone, respectively. The resulting PabC-PSDM-C343 undergoes a pH-induced coil-globule transition, which suggests that the distance between donor and acceptor is controllable by changing end-to-end distance of the backbone. The emission spectrum demonstrates that FRET occurs effectively below pH 7.0. Moreover, PEGylated system shows the enhanced dispersion stability compared with non-PEGylated system. |
