Enhanced Sensitivity of SPR-Based Biosensor for Waterborne Pathogen Monitoring: A Numerical Analysis

This numerical study proposes a novel surface plasmon resonance (SPR) based biosensor for sensitively detecting waterborne pathogens. The performance of the biosensor is improved by a multi-layered sensor structure that includes layers of BK7, silver, platinum (Pt), zinc oxide (ZnO), and lithium fluoride (LiF). Different target analytes were chosen, like Vibrio cholerae, Bacillus anthracis, E. coli, and Enterococcus faecalis cells. For the Enterococcus faecalis cell with a refractive index (RI) of 1.3921, the proposed biosensor observed the highest sensitivity of 269.512 degree per RI unit (deg/RIU). A figure of merit (FoM) of 48.21 was also attained, demonstrating the biosensor’s superior analytical capability. The transfer matrix method (TMM) was used in this numerical investigation for reflectance calculations. Monitoring aquatic pathogens has significantly advanced due to these results, providing an effective and extremely sensitive tool for environmental and public health applications.