Electrochemical system for detection of fermentation-derived bioethanol via cyclic voltammetry using nickel oxide modified glassy carbon electrode

Accurate detection of bioethanol is essential for optimizing biofuel production. Although precise, current industrial methods such as Gas chromatography (GC) and High-performance liquid chromatography (HPLC) are expensive, time-consuming, and unsuitable for on-site monitoring. This study explores the development of a cost-effective, rapid electrochemical method using nickel oxide (NiO)-modified glassy carbon electrodes for detecting bioethanol produced via fermentation using <i>Saccharomyces cerevisiae</i>. Fermentation was optimized with varying sucrose concentrations (20-100 g/L), achieving a maximum ethanol yield of 15.69 g/L at 40 g/L sucrose with an agitation of 100 rpm at 48 h. Distilled ethanol was characterized by GC and HPLC. Cyclic voltammetry (CV) was employed for electrochemical detection, with NiO nanoparticles synthesized and characterized using X-ray diffraction (XRD), confirming their crystalline structure and electroactive surface area. The CV analysis demonstrated clear anodic and cathodic peaks for standard and fermented bioethanol, with a cathodic peak at 0.43 V and an anodic peak at 0.52 V. The oxidation peak current showed a linear relationship with the scan rate, confirming a diffusion-controlled process. These findings confirm NiO-modified electrodes as a dependable ethanol detection method. As a scalable and sustainable substitute for traditional methods, the technique exhibits potential for non-enzymatic bioethanol monitoring in industrial settings.