Viral detection using an embedded piezoresistive microcantilever sensor

The detection of aerosol-based vaccinia virus and solution-based vaccinia virus has been studied using a new type of microsensor design. In the embedded piezoresistive microcantilever (EPM) sensor, a tiny piezoresistive microcantilever is embedded or partially embedded into an active sensing material whose volumetric response to the presence of an analyte is recorded as a strain in the cantilever, and subsequent change in the resistance of the cantilever. In one set of experiments, a composite consisting of poly(ethylene oxide), or PEO, combined with vaccinia antibody was used as the active sensing material. In aerosol exposures, this sensor produced a distinct signal owing to vaccinia virus adsorption/incorporation. In addition, experiments using a piezoresistive microcantilever in direct contact with a pure antibody layer in solution were also performed to detect vaccinia virus in solution. Again, a clear and distinct analyte signals obtained.