Sensitive determination of pesticide imidacloprid using a glassy carbon electrode modified with a film composed of multi-walled carbon nanotubes and poly(aspartic acid)

A new voltammetric sensor, based on multi-walled carbon nanotubes (MWCNTs) composite poly(aspartic acid) film modified glassy carbon electrode, was fabricated and used for determination of pesticide imidacloprid. The synergistic effect of MWCNTs and the polymer resulted in a significantly improved electrochemical response (in terms of sensitivity, accuracy and analytical range) towards imidacloprid. Under selective conditions, the determination linear range was from 1.53 x 10(-5) g L-1 up to 1.53 x 10(-2) g L-1 with a detection limit of 1.15 x 10(-5) g L-1 (S/N = 3). The sensor also had an easily renewable surface, good fabrication reproducibility, and inherent stability. Moreover, satisfactory results were obtained with complex samples and demonstrate the reliability of the proposed method.