Rapid and sensitive stripping voltammetric analysis of methyl parathion in vegetable samples at carboxylic acid-functionalized SWCNTs–β-cyclodextrin modified electrode

A rapid, sensitive and enzymeless methyl parathion (MP) electrochemical sensor based on carboxylic acid-functionalized single-walled carbon nanotubes–β-cyclodextrin modified glassy carbon electrode (ƒ-SWCNT–β-CD/GCE) was successfully constructed for the trace analysis of MP in vegetable samples. Cyclic voltammetry, differential pulse voltammetry, and electrochemical impedance spectroscopy were utilized to characterize the properties of the modified electrode. Experimental parameters such as preconcentration time, pH value, and the concentration of ƒ-SWCNT and β-CD were optimized. The proposed electrode displayed excellent electrocatalytic activity towards MP. The calibration curve for MP was obtained in both ranges of 0.002–0.02 μg mL−1 and 0.02–17.5 μg mL−1, with a low detection limit (S/N = 3) of 0.4 ng mL−1 after a very short preconcentration time for 80 s. The modified electrode exhibited fast current response, high sensitivity, good reproducibility, and satisfactory anti-interference ability, and also successfully employed for the trace analysis of MP in vegetables samples. Satisfactory results revealed that this proposed electrochemical sensor can provide a promising candidate for the trace analysis of MP in agricultural and environmental samples.