Development of MoS2 Modified SPE Based Electrochemical Immunosensors Sandwiched by Au NP Labeled Antibodies for Detecting Bovine rotavirus in Calves

<i>Bovine rotavirus</i> (BRV) is one of the leading causes of neonatal diarrhea in calves and remains a major concern in veterinary medicine due to its high morbidity and economic impact. Rapid, sensitive, and cost-effective diagnostic approaches are therefore required for early detection and disease control. In this study, electrochemical immunosensors were developed for the detection of BRV with the aim of improving existing multiplex diagnostic strategies. Screen-printed carbon electrodes (SPEs) were employed as the sensing platform and modified with molybdenum disulfide nanoparticles (MoS₂ NPs) to enhance electrochemical performance. Mouse monoclonal antibodies against the BRV VP6 protein were immobilized onto the electrode surface, followed by blocking with bovine serum albumin. BRV detection was carried out using differential pulse voltammetry, cyclic voltammetry, and electrochemical impedance spectroscopy. To further improve sensitivity, a sandwich immunoassay format was constructed using gold nanoparticle-labeled secondary antibodies. The MoS₂-modified sandwich immunosensor exhibited superior analytical performance, achieving a limit of detection of 1.11 ng/mL, a limit of quantification of 3.72 ng/mL, a relative standard deviation of 1.89% (<i>n</i> = 5), and a linear response with R² = 0.99. The developed immunosensors demonstrated reliable performance in real sample analysis, with a selectivity rate of 100 ± 2.95%. These findings suggest that MoS₂-based electrochemical immunosensors offer a promising platform for rapid and sensitive BRV detection and have potential applications in veterinary diagnostics.