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Voltage-clamp Fluorometry in Xenopus Oocytes Using Fluorescent Unnatural Amino Acids
Published on: May 27, 2017
Flavin-Based Light-Driven Fluorescent Probe for the Detection of Antioxidant Amino Acids
Kyeong-Im Hong1, Seong Min Lee1, Woo-Dong Jang1
1Department of Chemistry Yonsei University 50 Yonsei-ro, Seodaemu-gu Seoul 03722 Korea.
Abstract:
We have synthesized a flavin-N(5)-oxide derivative with a p-toluenesulfonyl (Ts-OF) group as a "turn-on" fluorescent probe for the detection of several antioxidant amino acids and biothiols. Oxidized flavin was synthesized by using dithiothreitol as the reducing agent. Ts-OF showed a light-driven fluorescence enhancement in the presence of several amino acids and biothiols such as histidine (His), methionine (Met), cysteine (Cys), glutathione (GSH), and homocysteine (Hcy). The 1H NMR study indicated the reductive elimination of the p-toluenesulfonyl group from Ts-OF in the presence of antioxidants and photo-irradiation.
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