A ratiometric fluorescence sensing system for rapid detection of glyphosate in miscellaneous beans

To establish a ratiometric fluorescence sensing system for the detection of glyphosate , nitrogen-sulfur doped carbon quantum dots nano-fluorescent probe was prepared by one-step hydrothermal method . At an excitation wavelength of 360 nm, the emission peak with maximum fluorescence intensity was obtained at 470 nm. The generation of 2.3-diaminophenazine by o-phenylenediamine oxidation produces a new fluorescence emission peak at 570 nm and a decrease in fluorescence at 470 nm. The fluorescence peaks at 470 and 570 nm form a ratio state. In the presence of glyphosate , reduces the oxidation of 2.3-diaminophenazine, this results in enhanced fluorescence at 470 nm and weakened fluorescence at 570 nm. Under the best conditions, the ratiometric fluorescence sensing system has good selectivity , the linear at glyphosate concentrations of 0.005–10 µg/mL, the limit of detection was 2.88 µg/kg, the limit of quantitation was 4.07 µg/kg. In addition, it is worth mentioning that this developed sensing system has shown good detection performance in 10 miscellaneous samples, the simple, efficient, and highly sensitive ratiometric fluorescence detection sensing strategy is provided.