Ultra-Sensitive Cholesterol Sensor Using Gold and Zinc-Oxide Nanoparticles Immobilized Core Mismatch MPM/SPS Probe

A newly developed localized surface plasmon resonance (LSPR) phenomenon-based cholesterol (Cho) sensor is reported in this article. Functional test of the proposed sensor over an ultra-wide-range of Cho concentration (0.1-10 mM) which covers the Cho concentration in human serum (~5.17 mM), revealing great performance is executed. Further, different structures such as multimode-photosensitive-multimode (MPM) and single-photosensitive-single (SPS), also called core mismatch fiber structure are presented here for the effective detection of Cho. The proposed sensors are immobilized with different sizes of gold nanoparticles (AuNPs) (~10 nm and ~30 nm) followed by zinc oxide NPs (ZnO-NPs). The characterization and functional test of nanomaterials (NMs) and immobilized probes are observed using a UV-Vis spectrophotometer, HR-TEM, AFM, SEM, and EDS. A noticeable improvement is recorded in the all-important sensing parameters of proposed sensors, such as i) sensitivity (0.6898 nm/mM), ii) linearity (0.1-10 mM), iii) limit of detection (LoD) (0.6161 mM), and iv) correlation coefficient (0.9754) on the course of the immune binding of Cho to a specific cholesterol-oxidase (ChOx) functionalized probe, exhibiting great potential for future practical applications.