Four-core fiber-based multi-tapered WaveFlex biosensor for rapid detection of Vibrio parahaemolyticus using nanoparticles-enhanced probes.

Infections caused by Vibrio parahaemolyticus (V. parahaemolyticus) can be highly fatal, making rapid and sensitive detection of them is essential. A new optical fiber biosensor based on localized surface plasmon resonance (LSPR) phenomenon is developed in this paper. A tapered-in-tapered fiber structure based on MFM is constructed by using four-core fiber (FCF) and multi-mode fiber (MMF) to qualitatively detect different concentrations of V. parahaemolyticus. The sensor successfully excites the LSPR phenomenon and increases the attachment point of biomolecules on the probe surface by fixing gold nanoparticles (AuNPs), molybdenum disulfide nanoparticles (MoS₂-NPs) and cerium dioxide nanorods (CeO₂-NRs). The functionalization of polyclonal antibodies on the probe surface can improve the specificity of the sensor. The linear detection range of the developed sensor was 1 × 10⁰-1 × 10⁷ CFU/mL, the sensitivity was 1.61 nm/[CFU/mL], and the detection limit was 0.14 CFU/mL. In addition, the reusability, reproducibility, stability, and selectivity of the sensor probe are also tested, which shows that the sensor has great application prospects.