Application of electrochemical biosensor in airborne virus protein collection devices

The influenza virus is a highly contagious pathogen transmitted via airborne droplets expelled during coughing or sneezing by infected individuals. Fine aerosolized viral particles can remain suspended in the air, particularly in enclosed environments, posing a significant risk of transmission. Exposure to high viral loads may lead to severe health outcomes. In this study, we advanced a previously developed airborne viral protein collection system by designing, fabricating, and evaluating three distinct electrochemical biosensors for integration with the device. To assess long-term stability, we compared two immobilization strategies: (1) thiolated short linkers (SH-linkers) and (2) the biotin–avidin/streptavidin binding system. The most effective sensor used a 10 μm comb-shaped capacitive gold electrode, functionalized with a self-assembled monolayer (SAM) of SH-biotin, streptavidin, and a biotinylated aptamer, which showed high specificity toward the H1N1 virus. Nonspecific binding was minimized through a BSA blocking step. The biosensor exhibited sensitive detection of H1N1 hemagglutinin (HA) protein across a dynamic range of 1 pg/mL to 1 ng/mL, with an impressive limit of detection (LOD) of 0.045 pg/mL. Preliminary assessments demonstrated favorable signal stability, with capacitance drift limited to 5 % over two days and 10 % over four days. Although further optimization is needed for extended continuous monitoring, the integrated collection and sensing platform holds significant potential. It can be further enhanced with wireless communication modules (e.g., Bluetooth), embedded signal processing circuits, and custom mobile applications for real-time data transmission and alerts. This system represents a proactive approach to airborne virus surveillance, contributing to early detection, timely warning, and effective mitigation of infectious disease spread. • Electrochemical sensor developed for viral detection in air collector system. • Immobilization strategies compared; sensor achieved pg/mL sensitivity and stability. • Portable system enables clinical and environmental biosensing.