Selective detection of Ochratoxin B in food by fluorescent sensor based on 2-mercapto-5-benzimidazole carboxylic acid-capped CdSe quantum dots

TL;DR

A new fluorescent sensor using CdSe quantum dots can selectively detect Ochratoxin B in food with high sensitivity and accuracy.

Contribution

A novel fluorescent sensor based on MBI-capped CdSe quantum dots for selective OTB detection is developed.

Findings

The sensor detects OTB with a detection limit of 0.016 ng/mL and a wide linear range.

It shows high selectivity for OTB over other mycotoxins like OTA.

The method achieves high recovery rates (96.51% to 104.7%) in real food samples.

Abstract

Ochratoxin B (OTB) that widely presented in food has significant cytotoxicity even at low concentration levels. Herein, a novel fluorescent sensor based on the 2-mercapto-5-benzimidazole carboxylic acid (MBI)-capped CdSe quantum dots (QDs) was established for the selective detection of OTB in food. Specifically, the synergistic effect of electrostatic interaction and intermolecular hydrogen bonds between MBI and OTB provided a direct and sensitive fluorescence signal that enables efficient recognition of OTB from other mycotoxins, even OTA with similar structures. Excellent linear detection performance for OTB is exhibited with a range from 0.037 ng/mL to 48.01 ng/mL and a detection limit of 0.016 ng/mL. Furthermore, our developed method exhibits good anti-interference stability against contaminants such as mycotoxins, inorganic salts and amino acids. Most importantly, the sensor demonstrates high sensitivity in real food samples with the recovery ranges from 96.51% to 104.7%, with an RSD of less than 2.67%.

•A novel fluorescent sensor based on the MBI-capped CdSe QDs was established.•The sensor enables efficient recognition of OTB from other mycotoxins, even OTA.•The detection performance for OTB exhibited with wide range and low detection limit.•The sensor demonstrates high sensitivity in real food samples.

A novel fluorescent sensor based on the MBI-capped CdSe QDs was established.

The sensor enables efficient recognition of OTB from other mycotoxins, even OTA.

The detection performance for OTB exhibited with wide range and low detection limit.

The sensor demonstrates high sensitivity in real food samples.

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