title: Discriminative fluorescence sensing of biothiols in vitro and in living cells.
abstract: Simultaneous discriminative sensing of biothiols in vitro and in living cells has remained challenging. Herein, we report a new sulfonamide-based self-quenched fluorescent probe 1 for this purpose with high sensitivity and good selectivity. Treatment of 1 with cysteine (Cys), homocysteine (Hcy), or glutathione (GSH) yields aminoluciferin, 2-cyano-6-aminobenzothiazole homocysteine (CBTHcy), or 2-cyano-6-aminobenzothiazole (CBT), turning "on" the fluorescence at wavelengths of 522, 517, or 490 nm, respectively. Kinetic study indicated that 1 reacts with Cys faster than with Hcy or GSH. With these unique properties of 1, we applied 1 for highly sensitive sensing of Cys, Hcy, and GSH among other 19 natural amino acids (AAs) with good selectivity. Confocal fluorescence microscopic imaging of 1-treated HepG2 cells at two channels (522 ± 8 and 490 ± 8 nm), together with quantitative analysis, indicated that the "turn-on" fluorescence was induced by intracellular Cys-dominating condensation and reduction of 1 but not by intracellular GSH-dominating reduction of 1. This suggests that 1 could be applied for discriminative sensing of intracellular Cys from the abundant GSH. Further development of 1 might bring about an efficient tool for probing cellular functions that relate to biothiols.
authors: †CAS Key Laboratory of Soft Matter Chemistry, Department of Chemistry and ‡Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors: Qingqing
authors: Q
authors: Miao
authors: †CAS Key Laboratory of Soft Matter Chemistry, Department of Chemistry and ‡Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors: Qing
authors: Q
authors: Li
authors: †CAS Key Laboratory of Soft Matter Chemistry, Department of Chemistry and ‡Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors: Qingpan
authors: Q
authors: Yuan
authors: †CAS Key Laboratory of Soft Matter Chemistry, Department of Chemistry and ‡Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors: Lingli
authors: L
authors: Li
authors: †CAS Key Laboratory of Soft Matter Chemistry, Department of Chemistry and ‡Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors: Zijuan
authors: Z
authors: Hai
authors: †CAS Key Laboratory of Soft Matter Chemistry, Department of Chemistry and ‡Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors: Shuang
authors: S
authors: Liu
authors: †CAS Key Laboratory of Soft Matter Chemistry, Department of Chemistry and ‡Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors: Gaolin
authors: G
authors: Liang
mesh_terms: D002021:Buffers; D002470:Cell Survival; D002623:Chemistry Techniques, Analytical / Q000295:instrumentation*; D015195:Drug Design; D005456:Fluorescent Dyes / Q000138:chemical synthesis / Q000737:chemistry; D056945:Hep G2 Cells; D006801:Humans; D006863:Hydrogen-Ion Concentration; D013050:Spectrometry, Fluorescence; D013438:Sulfhydryl Compounds / Q000032:analysis* / Q000737:chemistry
chemical_list: D002021:Buffers; D005456:Fluorescent Dyes; D013438:Sulfhydryl Compounds