Recent advances in the development of responsive probes for selective detection of cysteine

Fluorescent probes based on nucleophilic aromatic substitution reactions for reactive sulfur and selenium species: Recent progress, applications, and design strategies

“…Most fluorescent probes based on S N Ar reactions for RSS and RSeS can achieve the “off–on” effect after reaction with the analyte [7] , [8] . Benzenesulfonate [80] , [81] , [82] , [83] , [84] , [85] , [86] , [87] , [88] , phenyl-O ether [89] , [90] , [91] , [92] , [93] , [94] , [95] , [96] , [97] , [98] , phenyl-S ether [99] , [100] , [101] , [102] , phenyl-Se ether [103] , [104] , 7-nitro-2,1,3-benzoxadiazole (NBD) [105] , [106] , [107] , [108] , [109] , [110] , [111] , benzoate, and selenium-nitrogen bonds are all good detection groups [21] , [22] (see Table1 ).…”

“…2,4-Dinitrochlorobenzene (CDNB), p -nitrochlorobenzene (CNB), p -nitrobromobenzene, p -methoxychlorobenzene, and o -trifluoromethylfluorobenzene are small molecules of this type. Since phenyl itself also has an electron-withdrawing effect, fluorobenzene, chlorobenzene, and so on, can also be used as electrophiles [20] , [21] , [22] .…”

Detecting Cysteine in Bioimaging with a Near‐Infrared Probe Based on a Novel Fluorescence Quenching Mechanism

“…Over the last dozen years, many fluorescent probes for Cys sensing have been developed with highly sensitive, distinct fluorescence changes, real-time detection and noninvasiveness, as well as simplicity of operation. [13][14][15][16][17][18] However, most of them are limited by insufficient selectivity to discriminate Cys from other biothiols, in particular Hcy and GSH. Geometrically speaking, Hcy has a minor difference from Cys: an extra methylene unit in the side chain.…”

“…[15,16,[19][20][21][22][23][24][25][26][27] Despite significant advances, a great number of these fluorescent probes exhibited absorption and emission in the ultraviolet or visible-light range, which may be strongly interfered by biological autofluorescence. [13][14][15][16][17][18] On the other hand, near-infrared region (650-900 nm) fluorescent probes emissive have been developed for biothiols in favour of the advantages of minimal damage, less light scattering, deep tissue penetration, and low background interference. The most popular strategy for the development of Cysselective fluorescent probes is using Michael addition/intramolecular cyclizations of acrylic ester pioneered by Strongin's group to differentiate Cys between Hcy.…”

Development of “dual-key-and-lock” responsive probes for biosensing and imaging

“…Generally, the probes can be developed by integrating the reporter (signalling unit) with the biomarker recognition unit. 3,4 The most commonly signalling units are electrochemical sensors, 5,6 nuclear magnetic resonance contrast agents, [7][8][9] luminophore, [10][11][12][13][14] and photoacoustic agents. 15,16 After binding and/or interaction of biomolecules with the recognition unit, the signals from receptor could be recorded for the biomolecules detection.…”