Ankita Sinha

Polyaniline-graphene oxide nanocomposite sensor for quantification of calcium channel blocker levamlodipine.

A novel polyaniline-graphene oxide nanocomposite (PANI/GO/GCE) sensor has been fabricated for quantification of a calcium channel blocker drug levamlodipine (LAMP). Fabricated sensor has been characterized by electrochemical impedance spectroscopy, square wave and cyclic voltammetry, Raman spectroscopy and Fourier transform infrared (FTIR) spectroscopy. The developed PANI/GO/GCE sensor has excellent analytical performance towards electrocatalytic oxidation as compared to PANI/GCE, GO/GCE and bare GCE. Under optimized experimental conditions, the fabricated sensor exhibits a linear response for LAMP for its oxidation over a concentration range from 1.25μgmL(-1) to 13.25μgmL(-1) with correlation coefficient of 0.9950 (r(2)), detection limit of 1.07ngmL(-1) and quantification limit of 3.57ngmL(-1). The sensor shows an excellent performance for detecting LAMP with reproducibility of 2.78% relative standard deviation (RSD). The proposed method has been successfully applied for LAMP determination in pharmaceutical formulation with a recovery from 99.88% to 101.75%.

A polyaniline/graphene oxide nanocomposite as a voltammetric sensor for electroanalytical detection of clonazepam

A voltammetric sensor based on a polyaniline/graphene oxide modified glassy carbon electrode (PANI/GRO/GCE) has been developed for the ultrasensitive voltammetric detection of clonazepam (CZPM). The synthetic PANI/GRO nanocomposite along with its precursors PANI and GRO has been characterized by various spectral techniques like infrared and Raman spectroscopy, scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) and voltammetric techniques like square wave and cyclic voltammetry. Under optimized conditions, the PANI/GRO/GCE showed a well-defined reduction peak in Britton–Robinson buffer at pH 8.8 in ethyl alcohol. The square wave cathodic current exhibits a linear response to clonazepam over a concentration range of 10 (ng mL−1) to 550 (ng mL−1) with a correlation coefficient (r2) of 0.9935, a detection limit (LOD) 4.63 ng mL−1 and a quantification limit (LOQ) 15.44 ng mL−1. The proposed method for quantification of CZPM demonstrates the enhanced catalytic response of the PANI/GRO/GCE with a reproducibility of 4.21% relative standard deviation (RSD) and a satisfactory recovery from 97.16% to 102.78%.