Rapid detection of carbamate pesticide residues using microchip electrophoresis combining amperometric detection

The long-term consumption of food with pesticide residues has harmful effects on human health and the demand for pesticide detection technology tends to be miniaturized and instant. To this end, we demonstrated the first application of indirectly detecting two carbamate pesticides, metolcarb and carbaryl, by gold nanoparticle-modified indium tin oxide electrode in dual-channel microchip electrophoresis and amperometric detection (ME-AD) system. m-Cresol and alpha-naphthol were obtained after pesticide hydrolysis in alkaline solution, and then separated and detected by ME-AD. Parameters including the detection potential and running buffer concentration and pH were optimized to improve the detection sensitivity and separation efficiency. Under the optimal conditions, the two analytes were completely separated within 80 s. m-Cresol and alpha-naphthol presented a wide linear range from 1 to 100 mu M, with limits of detection of 0.16 mu M and 0.34 mu M, respectively (S/N = 3). Moreover, the reliability of this system was demonstrated by analyzing metolcarb and carbaryl in spiked vegetable samples.

Automated summary

The study demonstrated the successful detection of two pesticide residues using a gold nanoparticle-modified indium tin oxide electrode in combination with dual-channel microchip electrophoresis and amperometric detection system, achieving rapid and highly sensitive detection. Through hydrolysis and optimized operating conditions, accurate separation and detection of pesticide residues can be carried out.