High-Sensitive Detection of E. coli Bacteria Based on Low-Etching Current Density Meso Porous Silicon Electrical Sensor

Abstract

Escherichia coli (E. coli) bacteria identification is important in many areas, such as environmental monitoring and medical diagnostics. Conventional techniques frequently lack specificity and sensitivity. This study investigates the fabrication and characterization of a high-sensitive E. coli bacteria sensor using mesoporous silicon prepared by an electrochemical etching process under different low current densities. This study explores a high-sensitive E. coli sensor grown in nutrient agar at 36.5 °C, deposited on the mesoporous silicon surface, with morphology analyzed using scanning electron microscopy (SEM) and current–voltage characteristics measured. The XRD analysis confirmed the peaks of silicon material with a polycrystalline nature. FTIR demonstrated Si–H bonds which approve the porosity process. Results indicated that silicon etched at 3 mA/cm² had small slit mesopores and large nanoparticles (73–102 nm) and at 9 mA/cm², the smallest non-aggregated nanoparticles (54–83 nm) and largest pores (20 nm) were achieved. This study concludes that mesoporous silicon etched at 9 mA/cm² provides the best performance for E. coli detection, demonstrating its potential for high-quality biosensor applications.