Developing a DNA-biosensor for the detection of flutamide using electrochemical method

Ali A. Ensafi, Nahid Khademi Farfani, B. Rezaei, Maryam Amini,

Abstract

An uncomplicated and selective method was applied to expand a novel electrochemical DNA biosensor for the determination of flutamide. This biosensor was composed of pretreated screen printed electrode (SPE) that was modified with reduced graphene oxide (rGO) and decorated with ds-DNA. This biosensor, which was simple and inexpensive, was applied via the interaction of small molecules such as flutamide with the DNA. This study describes the use of DNA-based biosensor in order to determine trace amounts of flutamide. First of all, the interaction of salmon sperm ds-DNA with flutamide on the surface of ds-DNA modified rGO-SPE (ds-DNA/rGO/SPE) was examined. The oxidation currents of guanine and adenine were applied as probes in order to peruse the resulting interaction. Through the interaction of flutamide with the DNA, the oxidation currents of guanine and adenine declined at the ds-DNA/rGO/SPE, by using differential pulse voltammetry (DPV). There was a linear dependence of the adenine oxidation currents and the flutamide concentration in the range of 0.0025 - 0.0750 and 0.0750-7.500 nmol L^-1 (at the optimum conditions), with a limit of detection 1.5 pmol L^-1. The relative standard deviations (RSD) for five replicate measurements of 0.05 and 5.00 nmol L^-1 flutamide were obtained 4.5 and 3.5% using the adenine signal. This method was

successfully applied to determine the trace amount of flutamide in real samples. This study was conducted using SPE as a working electrode, the electrochemical impedance spectroscopy (EIS) and UV–Vis spectroscopy methods too.

Keywords: DNA–biosensor, Flutamide, Reduced graphing oxide modified screen printed electrode, Differential pulse voltammetry.