Fabrication of nanoclay-modified electrodes and their use as an effective electrochemical sensor for biomedical applications

Abstract

Famotidine (FAM) is used in the treatment of stomach ulcers and intestines by decreasing the concentration of acid (e.g., Zollinger-Ellison syndrome) produced in the stomach. FAM can prompt impaired mental conditions and cause kidney disease in older adults. This drug is listed as a persistent contaminant in the environmental samples. In this regard, FAM determination was carried out in urine and pharmaceutical samples utilizing a sensitive sensor. Novel clay nanosheets were fabricated through an ultrasonication-assisted process, and utilized nanoclay to surface modify the carbon paste electrode (NC/CPE), and employed for investigating electrooxidation of famotidine (FAM) in 0.2 M phosphate buffer solution (PBS) of pH 5.0. The sensing vicinity of the electrode is increased by nanoclay sheets; hence improvement in the interaction of FAM was achieved, which results in enhanced oxidation peak current than bare CPE. Based on the estimated interaction parameters, the involvement of a number of electrons during oxidation was calculated as one, and a heterogeneous constant (k0) was found to be 3.66 × 103s−1. The values of the detection limit and the quantification limit were determined to be 3.7 × 10–8M and 12.5 × 10–8M, respectively. The designed electrode was showed an intensification of peak current with better sensibility, stability, reproducibility, repeatability, along with the existence of substances that interfere with the biological systems. Comfortable values of recovery were achieved via the analysis of FAM in urine (97.6–98.3%) and medicinal samples (91.83–98.37%). The study suggests that the use of nanoclay as a modifier was significantly influenced the electrochemical properties.