Fabrication of high performance disposable screen printed electrochemical sensor for ciprofloxacin sensing in biological samples

In this paper, we report a facile one step electrochemical method to synthesize a highly sensitive nanocomposite film based on gold nanoparticles (AuNPs) and chitosan (CHI) polymer on disposable screen printed electrode (SPE). We have demonstrated that AuNP/CHI composite film based fabricated sensor exhibited distinctly higher electrochemical behavior towards oxidation of ciprofloxacin (CF) due to excellent conducting properties of the gold metal nanoparticles incorporated in chitosan matrix. Electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and square wave voltammetry (SWV) were used for electrochemical characterization of modified electrodes. Morphological characterization was carried out by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). AuNP/CHI/SPE sensor displayed excellent conductive properties for CF oxidation with higher oxidation current, which enabled us to employ AuNP/CHI/SPE as an electrochemical sensor for CF detection. Electrochemical parameters were optimized and kinetic parameters at AuNP/CHI/SPE were also explored. CF showed good linearity at proposed sensor over the range of 0.1-150 mu M with detection limit of 0.001 mu M. Further, fabricated sensor showed good stability, selectivity and sensitivity. Finally sensor was successfully employed for CF determination in biological samples.