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Updated: Jun 25, 2026

Examining the Conformational Dynamics of Membrane Proteins in situ with Site-directed Fluorescence Labeling
Published on: May 29, 2011
One- and two-photon turn-on fluorescent probe for cysteine and homocysteine with large emission shift
Xuanjun Zhang1, Xinsheng Ren, Qing-Hua Xu
1Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore.
Abstract:
A novel dendritic chromophore with efficient intramolecular charge transfer (ICT) and strong two-photon absorption (TPA) was designed as a turn-on fluorescent probe for cysteine (Cys) and homocysteine (Hcy). The probe exhibited greatly enhanced fluorescence intensity as well as a very large emission peak shift (165 nm) upon addition of Cys/Hcy due to ICT switch off. The sensing process was also monitored by two-photon excited fluorescence (TPEF).
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