A High Sensitive Nanomaterial Coated Side Polished Fiber Sensor for Detection of Cardiac Troponin I Antibody.

The advent of evanescent field based fiber optic biosensor and advancements in nanotechnology has create an excellent opportunity in label-free detection of biomarkers which plays vital role in the early, rapid and accurate diagnosis of acute diseases. In this work, we demonstrate a high sensitive Molybdenum Tungsten Disulfide (MoWS2) coated side polished fiber (SPF) biosensor for accurate and early diagnosis of cardio vascular disease (CVD). The Cardiac Troponins I (cTnI) is identified as a biomarker of interest for early and rapid diagnonis of CVD. The proposed SPF biosensor exhibits surface plasmonic resonance (SPR) detection due to the evanescent field interaction between MoWS2 nano coated side polished region and anti-CTnI. The proposed SPF biosensor possess the high sensitivity of 82% to detect the cTnI antibody with a limit of detection (LOD) about 17.5 pg/mL. The peak SPR shift have been calculated as 61 nm for analyte concentrations of 500 pg/mL Moreover, the proposed SPF biosensor possess the high degree of selectivity and environmental stability to CTnI among three analytes such as CTnI, Estrogen and Glucose. The hydrophobic interactions of MoWS2 and cTnI antibody leads to chemical free biofunctionalization of antibody in the sensing region. Hence, the simulation results shows the surface interaction strength calculated as 1.29 KJ mol^-1/nm² in order to evaluate the hydrophobic interactions. Thus, the proposed optical biosensor is a promising candidate for "point-of-care" testing of CVD disorders and preclinical assessments.