High-Performance Olfactory Receptor-Derived Peptide Biosensor for Acetic Acid Gas Detection Based on Polystyrene Microsphere Templates

Acetic acid gas, as an organic pollutant, poses serious hazards to both human health and the environment. Consequently, the real-time detection of low concentrations of acetic acid gas has become a matter of considerable concern. In this study, a bioelectronic sensor was synthesized by directly coupling N-terminal cysteine-modified olfactory receptor-derived peptide with thioester-functionalized single-walled carbon nanotubes through chemical linkage, and its performance was experimentally tested. More importantly, to further enhance its performance, polystyrene microsphere templating was employed during synthesis, this improvement significantly improved the overall performance of the sensor compared to the original process, and then characterization and gas sensitivity tests were carried out. The results revealed that the sensor exhibited extremely high sensitivity, with a detection limit 1 order of magnitude lower than that of the sensor fabricated without the template, reaching 1 ppt at room temperature. This detection limit is 2-3 orders of magnitude lower than that of conventional devices. Moreover, the sensor demonstrated excellent selectivity, stability, and rapid response characteristics.