Electrochemical Detection of Selected Pathogens (E-Coli and S-Typhi) By Bioreduced Nickel Nanoparticles

E-coli and S-typhi detection suffers from slow analysis time and high costs, along with the need for specificity. While state-of-the-art electrochemical biosensors are cost-efficient and easy to implement, their sensitivity and analysis time still require improvement. This paper present an electrochemical method of detecting pathogens using NiNPs to achieve fast detection, low cost, and high sensitivity. Using voltametric techniques as the detection technique, the biosensor achieved a limit of detection of 2.7 × 102 and 1.6 × 103 CFU/mL for E. coli and E-typhi respectively across a concentration range of 102–108 CFU/mL. This provides rapid, highly sensitive E. coli and E-typhi detection with a fast analysis time of 30 min. Nickel nanoparticles were biosynthesized at different pH using. The nanoparticles were characterized using UV-Visible, Fourier Transform Infrared, X-ray Diffraction and Scanning Electron Microscope. The microbial assay was ascertain using cyclic voltametric method. The results confirm the formation of nickel nanoparticles at wavelength of 423nm and due to the spherical shape as confirmed by scanning electron microscope. The nickel nanoparticles revealed the oxidation-reduction reaction using cyclic voltametric analysis. The voltamogram was further characterized by the oxidation peat at approximately 70mV attributed to the presence of S-typhi, similarly, the oxidation peak of approximately 60mV correspond the presence of E-coli in the sample. This study, which combines the detection advantages of electrochemical systems, has the potential to meet the needs of point-of-care applications. It is thought that future studies that will aim to examine the performance of the production-optimized, portable, graphite-based sensor system on real food samples, environmental samples, and especially medical clinical samples will be promising.