Clay-based carbon sensor for electro-oxidation of nimesulide

An effective voltammetric method has been demonstrated for the discovery and determination of the drug nimesulide (NMS) in the phosphate buffer solution (PBS) at bentonite clay (BNC) modified carbon paste electrode (CPE). Utilizing the voltammetric approaches such as cyclic voltammetry (CV) and square wave voltammetry (SWV), an impression of several electro-kinetic parameters such as heterogeneous rate, temperature influence, transfer coefficient, scan rate, pH, accumulation period, activation energy, and applicability to biological as well as pharmaceutical samples have been disclosed. The number of electrons along with protons engaging in electro-oxidation of NMS has been defined. The developed sensor substantiated sensibility, elevated peak current, great stability, appreciative recovery analysis with favorable reproducibility and repeatability. The sensor was also used to analyze NMS in real samples. The bentonite clay modified carbon paste electrode (BNC/CPE) sensor has been viewed as sensitive for NMS detection due to improved catalytic characteristics to peak current in 9.2 pH phosphate buffer solution (PBS) of ionic strength 0.2 M which contributed to the sensor's good sensing performance. The peak current was noted to be 29.61 μA with peak potential of 0.8731 V for BNC/CPE and the peak current which was noted for the bare carbon paste electrode (BCPE) was 3.76 μA with the peak potential of 0.8829 V. The NMS has a detection limit of 1.10 × 10−8 M and a quantification limit of 8.7 × 10−8 M. The biological and pharmaceutical samples showed peak potential at 0.8474 V for different concentrations of NMS. The current method found to be a highly sensitive technique for the determination of NMS in real samples. A righteous mechanism for electro-oxidation of NMS was speculated. [Display omitted] •Electrochemical investigation of NMS was carried out at clay modified electrode.•The electrochemical reaction was diffusion-controlled with two electrons involvement.•Thermodynamic parameters have been quantified.•Analysis of NMS in biological and pharmaceutical samples was done using BNC/CPE.