A New Red-Emitting Fluorescence Probe for Rapid and Effective Visualization of Bisulfite in Food Samples and Live Animals

Abstract

Development of new method for rapid and effective detection of bisulfite (HSO3-) in food samples and imaging of HSO3intake in animals is of significant importance due to key roles of HSO3in food quality assurance and community health. In this work, a new responsive fluorescence probe, EQC is reported for quantitative detection of HSO3in food samples and visualization of HSO3intake in animals. Upon addition of HSO3-, UV-vis absorption and red emission of EQC were significantly decreased within 120 seconds. The changes of absorption and emission spectra of EQC were rationalised by theoretical computation. The proposed reaction mechanism of EQC with HSO3was confirmed by high-resolution mass spectrometry (HRMS) and spectroscopic titration measurements. EQC has the advantages of high sensitivity, selectivity (a detection limit of 18.1 nM), and fast response towards HSO3-, which enable rapid and effective HSO3detection in buffer solution. The practical applications of EQC were demonstrated by the detection of HSO3in food samples and the imaging of HSO3intake in live animals.

Red-Emission Probe for Ratiometric Fluorescent Detection of Bisulfite and Its Application in Live Animals and Food Samples

“…Among the reported HSO 3 – detection methods, − such as spectrophotometry, chromatography, and capillary electrophoresis, fluoremetry has drawn increasing attention due to its obvious advantages such as excellent sensitivity, selectivity, capability of detection in situ, and easy for naked-eye visualization. − To date, a number of molecular fluorescence probes for HSO 3 – have been developed by exploiting several response reaction mechanisms, such as a nucleophilic reaction with aldehyde, − deprotection of the levulinate group, hydrogen bonding, and a nucleophilic addition reaction with the CC bond. − Of these fluorescence probes, ratiometric florescence probes with the improved signal-to-noise ratio are more reliable for the detection of HSO 3 – . − However, some problems of these reported fluorescent probes are (i) relatively long reaction time (30 min to 10 h) and (ii) poor selectivity and sensitivity . These limitations seriously retarded the application of the fluorescence probe for the detection of HSO 3 – in biological and food samples.…”

“…The large π-conjugation system, thus formed, with typical intramolecular charge transfer (ICT) character endows probe BIQ with a red emission at 625 nm. In the presence of HSO 3 – , the electron-deficient CC double bond linker is able to react with HSO 3 – through an established mechanism of the 1,4-addition reaction. − As a result, the π-conjugation system of BIQ is interrupted, resulting in dramatic changes of ultraviolet–visible (UV–vis) absorption and fluorescence spectra. Introducing an electron withdrawing group (−CN) promoted the reaction between CC bond and HSO 3 – to be completed within 2 min.…”

A Redox-Switchable Colorimetric Probe for “Naked-Eye” Detection of Hypochlorous Acid and Glutathione

“…1-Ethyl-2-methylquinolinium iodide was prepared according to our reported methods [48,49]. 2-Methylquinoline, iodoethane, 2-hydroxy-5-methoxy benzaldehyde were purchased from Aladdin reagent Co. (Shanghai, China).…”

A ratiometric fluorescent probe for the rapid and specific detection of HSO3− in water samples

“…− detection methods such as electrochemistry, [16] chromatography, [17] and spectroscopy, [18] fluorescence analysis has received much attention due to its high specificity and sensitivity, real-time monitoring, and in situ analysis. [19][20][21][22][23][24][25] To date, many various types of fluorescent probes have been developed for HSO 3 − . However, many of these are single-signal fluorescent probes [26][27][28][29][30][31][32][33][34][35] that are often influenced by many factors such as external detection environment conditions, photo-bleaching effects, stability of instruments, background signals, and probe distribution.…”