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Published on: February 28, 2015
A reaction-based sensing scheme for gold species: introduction of a (2-ethynyl)benzoate reactive moiety
Hyewon Seo1, Mi Eun Jun, Olga A Egorova
1Department of Chemistry and Center for Electro-Photo Behaviors in Advanced Molecular Systems, Pohang University of Science and Technology, San 31, Hyoja-dong, Pohang, 790-784, Republic of Korea.
Abstract:
To alleviate side reactions identified in an N-propargyl-rhodamine lactam sensing system, we devised the novel reaction-based sensing scheme for gold species based on the alkynophilicity. A fluorescein (2-ethynyl)benzoate underwent Au(III)-promoted ester hydrolysis selectively over other metal ions with high sensitivity, which accompanies a turn-on fluorescence change in pH 7.4 HEPES buffer. The work offers a versatile reactive moiety for the development of gold probes with improved sensing properties.
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