Benzimidazole‐based turn‐on fluorescence probe developed for highly specific and ultrasensitive detection of hypochlorite ions in living cells

Abstract

Hypochlorite (ClO−), as one of the active oxygen species (ROS), plays an essential role in the cellular defence system and organism immunity. In this paper, we successfully synthesized a new ‘turn‐on’ fluorescent probe BMF based on benzimidazole and characterized it by spectroscopic methods. The designed probe can quickly respond to ClO− with the obvious colour change from pink to colourless. Notably, the probe BMF exhibited almost no fluorescence, but showed strong fluorescence after adding ClO−, including an excellent fluorescence turn‐on effect. The fluorescence turn‐on phenomenon of BMF was attributed to the strong oxidation of ClO−, which severed the connecting double bond and disrupted the intramolecular charge transfer (ICT) system, plus light‐induced electron transfer effect between the fluorophore and the recognition group was discontinued. In addition, the cytotoxicity assay showed that the probe had lower cytotoxicity. Based on these advantages, we demonstrated that probe BMF might be a good candidate for detecting ClO− in biological systems.

A March to Shape Optical Artificial Olfactory System toward Ultrasensitive Detection of Improvised Explosives

“…From the research on optical detection of IEs from 2010 to 2021 ( Figure ), it can be found that the detection limits of hypochlorite, [ 41–57 ] perchlorate, [ 58–60 ] peroxide, [ 61–77 ] nitrate, [ 78–85 ] and nitrite [ 86–99 ] based on solution reaction are mostly between 10 −5 and 10 −9 M , and it is difficult to achieve higher sensitivity detection by merely optical probes designing. By combining the sensing probes with paper‐based [ 19,100–103 ] and hydrogel‐based [ 28,104–106 ] substrate and optical microscope device, the detection sensitivity has been greatly improved in 2020 and 2021 reaching a level of 10 −15 M. To better improve the detecting sensitivity, optical artificial olfactory system takes chemical sensor array as the detection modules of different IEs, as well as considering the automatic analyte collection with airflow and the ultrasensitive ecognition of optical signals has been explored from the design of different components.…”

“…Researches on optical detection of hypochlorite, [ 41–57 ] perchlorate, [ 58–60 ] peroxide, [ 61–77 ] nitrate, [ 78–85 ] and nitrite [ 86–99 ] IEs from 2010 to 2021 and sensors with paper‐based [ 19,100–103 ] and hydrogel‐based [ 28,104–106 ] substrate and optical microscope device. The first Figure from left on bottom reproduced with permission.…”

“…The third Figure from left on bottom reproduced with permission. [ 57 ] Copyright 2021, John Wiley & Sons, Ltd. The left Figure on top reproduced with permission.…”

“…For the realization of detecting more IEs, our group explored and integrated a series of colorimetric principles for the detection of potassium permanganate, S, urea, sugar, and other components of IEs. [28] From the research on optical detection of IEs from 2010 to 2021 (Figure 3), it can be found that the detection limits of hypochlorite, [41][42][43][44][45][46][47][48][49][50][51][52][53][54][55][56][57] perchlorate, [58][59][60] peroxide, [61][62][63][64][65][66][67][68][69][70][71][72][73][74][75][76][77] nitrate, [78][79][80][81][82][83][84][85] and nitrite [86]…”

“…[112] Shoronia et al used 4-dimethyl-aminocinnamaldehyde to react with nitrourea in neutral environment to form a red protonated Schiff base structure, which is the condensation reaction product between amino group and carbonyl group, and thus realized the detection of residue on fingers (Figure 4b). [113] The reaction Researches on optical detection of hypochlorite, [41][42][43][44][45][46][47][48][49][50][51][52][53][54][55][56][57] perchlorate, [58][59][60] peroxide, [61][62][63][64][65][66][67][68][69][70][71][72][73][74][75][76][77] nitrate, [78][79][80][81][82][83][84][85] and nitrite…”