Fast, sensitive and selective simultaneous determination of paraquat and glyphosate herbicides in water samples using a compact electrochemical sensor
Suphatsorn Thimoonnee, Kanpitcha Somnet, Pattanun Ngaosri, Sanoe Chairam, Chanpen Karuwan, Wichayaporn Kamsong, Adisorn Tuantranont, Maliwan Amatatongchai
Abstract
by chemical reduction. Finally, the dual-MIP was successfully coated on the MSN-PtNP core. This 3D-surface-imprinting strategy enhances the conductivity and monodispersity of the MSN-PtNPs@d-MIP. Quantitative analysis was performed by differential pulse voltammetry with an oxidation current appearing at -0.95 V for PQ and +0.97 V for GLY. The dual-MIP sensor shows good linear calibration curves in the range of 0.025-500 μM for both analytes with detection limits of 3.1 nM and 4.0 nM for PQ and GLY, respectively. The dual-MIP sensor shows high selectivity and specificity, attributed to the increased affinity of the imprinted cavities formed on the polymer film for the target PQ and GLY molecules. The proposed dual-MIP sensor was successfully applied to detect PQ and GLY concentrations simultaneously in water samples. The ready-to-use dual-MIP sensor is well suited for water-quality control and on-site applications without sophisticated instrumentation.