All-Step-in-One Test Kit for Paraquat Detection in Water and Vegetable Samples

This work presents the first development of an all-steps-in-one test kit for determination paraquat in natural water, and vegetable agricultural samples. A handheld photometer incorporated with a magnetic stirrer was used to complete steps extraction, mixing, detection. Paraquat produces blue free radical ion via reduction sodium dithionite alkaline conditions. Sodium powder investigated enhancement reagent stability duration, which added directly into sample solution that showed insignificant difference sensitivity as compared format dithionite. The developed good performance linear calibration 0.5 10 mg L−1 high coefficient (r2 = 0.9947). lower limit quantitation (LLOQ 3SD intercept per slope) carried out from method using 0.50 L−1. detection (LOD) by naked eye 0.30 recovery study acceptable range 101–115%. Intraday (n 3) interday precision less than 1%. On basis significance at 95% confidence interval, quantitative results agreed well those high-performance liquid chromatography (HPLC). To best our knowledge, this is report demonstrating online extraction vegetables kit, applicable on-site analysis. Single-point based on Beer–Lambert law also demonstrated measurement paraquat. In testing nominal standard 5.00 paraquat, reading concentration 5.09 ± 0.03 20) K value 0.0967 (close slope multipoint calibration). research direct benefit products health population analysis pesticides herbicides.