A Triple-Emission Fluorescent Probe for Discriminatory Detection of Cysteine/Homocysteine, Glutathione/Hydrogen Sulfide, and Thiophenol in Living Cells

Abstract

Thiols, such as cysteine (Cys), homocysteine (Hcy), glutathione (GSH), hydrogen sulfide (HS), and thiophenol are metabolically correlated with each other via redox reactions. As a result of the similarity of chemical properties between Cys, Hcy, GSH, HS, and thiophenol, it is very challenging to develop an effective methodology to differentiate them. In this work, a triple-emission fluorescent probe, NCQ, was reported for the simultaneous detection of Cys/Hcy, GSH/HS, and thiophenol with high sensitivity and selectivity. The solution of NCQ displayed distinct fluorescent signals toward Cys/Hcy, GSH/HS, and thiophenol: blue and green for Cys/Hcy, blue for GSH/HS, blue and red for thiophenol. Through the blue-green-red emission color combination, Cys/Hcy, GSH/HS, and thiophenol could be discriminatively detected in solution and in living cells.

The Role of Amino Acids in Neurotransmission and Fluorescent Tools for Their Detection

“…Many previously reported efforts have focused on the synthesis of dyes for cysteine detection, with at least 24 synthetic dye-based reported to function in detecting cysteine in the past five years (Table 2) [ 257 , 258 , 259 , 260 , 261 , 262 , 263 , 271 , 272 , 273 , 274 , 275 , 276 , 277 , 278 , 279 , 280 , 281 , 282 , 283 , 284 , 285 , 286 , 287 , 288 ]. Of these, several can be targeted to the mitochondria [ 262 , 282 , 285 , 286 ], the Golgi apparatus [ 259 , 276 ], the endoplasmic reticulum [ 274 , 275 ] and the lysosome [ 277 ].…”

“…Of these, several can be targeted to the mitochondria [ 262 , 282 , 285 , 286 ], the Golgi apparatus [ 259 , 276 ], the endoplasmic reticulum [ 274 , 275 ] and the lysosome [ 277 ]. Five act as non-specific sensors, detecting cysteine and other molecules that contain thiol groups or cysteine metabolites, with some using different wavelengths to distinguish between the different ligands [ 258 , 271 , 273 , 280 , 283 ]. These synthetic sensors all require irreversible reactions to detect cysteine, negatively affecting kinetics and requiring at least 5 min to an hour for maximum fluorescence [ 257 , 259 , 260 , 262 , 271 , 272 , 273 , 274 , 275 , 276 , 277 , 278 , 279 , 280 , 281 , 282 , 283 , 284 , 285 , 286 , 288 ].…”

Recent Progress in the Development of Fluorescent Probes for Thiophenol

“…By integrating different fluorophores and reaction sites into a single molecular probe, Song et al established a potent sensing platform (probe 44 ) for differentiating various thiols (including Cys/Hcy, GSH/H 2 S, and thiophenol) [112]. Probe 44 incorporated three latent fluorometric fluorophores, blue-emitting coumarin, green-emitting NBD, and a red-emitting coumarin analogue.…”

“…( b ) Images of Hela cells incubated with different regents. Reproduced with permission from Reference [112]; copyright American Chemical Society.…”

Dual-Function Fluorescent Probe for Detection of Hydrogen Sulfide and Water Content in Dimethyl Sulfoxide

“…Hydrogen sulfide (H 2 S) is a typical active sulfide compound. 1,2 H 2 S is of great importance physiologically and pathophysiologically. 3,4 Increased H 2 S content may increase the risk of various diseases, including ischemic disease, 5 atherosclerosis, 6 tumor, 7 diabetes, 8 and cardiac hypertension.…”