A Novel Thiophene-Based Fluorescent Chemosensor for the Detection of Zn2+ and CN−: Imaging Applications in Live Cells and Zebrafish

Abstract

A novel fluorescent turn-on chemosensor DHADC ((E)-3-((4-(diethylamino)-2hydroxybenzylidene)amino)-2,3-dihydrothiophene-2-carboxamide) has been developed and used to detect Zn 2+ and CN − . Compound DHADC displayed a notable fluorescence increase with Zn 2+ . The limit of detection (2.55 ± 0.05 µM) for zinc ion was far below the standard (76 µM) of the WHO (World Health Organization). In particular, compound DHADC could be applied to determine Zn 2+ in real samples, and to image Zn 2+ in both HeLa cells and zebrafish. Additionally, DHADC could detect CN − through a fluorescence enhancement with little inhibition with the existence of other types of anions. The detection processes of compound DHADC for Zn 2+ and CN − were demonstrated with various analytical methods like Job plots, 1 H NMR titrations, and ESI-Mass analyses.

A benzimidazole-based new fluorogenic differential/sequential chemosensor for Cu2+, Zn2+, CN-, P2O74-, DNA, its live-cell imaging and pyrosequencing applications

“…S10A and S10B). These are comparable to the values reported for other chemosensors for Cu 2+ and Zn 2+ ions [64][65][66][67][68][69] and adequate to recognize Cu 2+ and Zn 2+ ions in biological systems [70,71].…”

A Comprehensive Review on Thiophene Based Chemosensors

“…Moreover, investigating the practical applications of the probe, it was observed that sensor 42 filter paper could detect CN − , which is evident by the color change from blue to yellow and the LOD was noted to be 0.89 µM [86], implying that the probe could be implemented for the detection of CN − ions. From the results, it was then confirmed that the probe [87] could be utilized for the selective detection of CN − by the fluorescent turn-on method in aqueous systems.…”

“…The LOD for CN − was 44.6 µM, and the detection process was proposed through H-NMR titrations, which showed that deprotonation of the probe could result in the ICT suppression, thereby inducing fluorescence ‘turn-on’ of probe 43 -H + ( Scheme 40 ) . From the results, it was then confirmed that the probe [ 87 ] could be utilized for the selective detection of CN − by the fluorescent turn-on method in aqueous systems.…”

A Novel and Reactive Fluorescent “Turn‐on” Probe Based on Benzimidazole Derivative for Selective CN−Detection

“…The approaches for CN − detection, such as potentiometric and conventional titrations, are time‐consuming and require skillful handling. Therefore, a large number of selective sensors have been developed and provide convenient and rapid strategies for CN − detection [39–52] . The fluorescent chemical sensors exhibit many satisfactory characteristics such as high sensitivity and selectivity, visual detection and optical imaging [53–68] .…”