BSA-carbon dots a promising “off–on” fluorescence probe for detecting glyphosate residues in agricultural products

The widespread and extensive use of glyphosate in agriculture has raised concerns about its potential impact on the quality and safety of agricultural products. Conventional detection methods require long analysis times, making them impractical for the rapid detection of large quantities of samples. Therefore, developing a fast and simple detection system for glyphosate pesticide residues is urgent. In this study, the development of a facile fluorescence probe synthesized using a simple one-pot hydrothermal method for the determination of glyphosate is an important step toward addressing the need for a fast and simple detection system. The present sensor was created using bovine serum albumin (BSA) as a precursor, and the sensor operates by producing an “off–on” fluorescent signal. The bovine albumin-derived BSA-CDs emitted light yellow fluorescence, but this fluorescence was quenched (or suppressed) by the presence of Cu 2+ ions. However, the fluorescence can be restored by the presence of glyphosate, which interacts with the Cu 2+ ions to form a complex and release the BSA-CDs from suppression. The functional groups in glyphosate can capture Cu 2+ and break the BSA-CDs/Cu 2+ combinatorial system. The BSA-CDs/Cu 2+ fluorescence quenching system had good selectivity for glyphosate. The detection limit of the BSA-CD/Cu 2+ fluorescence sensor was 0.05 µg/mL. This developed method was utilized to successfully detect glyphosate in Chinese wheat. The average recoveries ranged from 98.9 to 100.7%, with a relative standard deviation < 3.0%, showing good prospects for practical applicability.