Aptasensor for Staphylococcus Enterotoxin B Detection Using High SNR Piezoresistive Microcantilevers

This paper proposes and demonstrates aptasensors for the detections of staphylococcus enterotoxin B (SEB) both in buffer and skim milk by using thiol-modified piezoresistive microcantilever. With attempts to optimize the design and fabrication processes of the microcantilever, the signal-to-noise rate of the aptasensor was greatly improved and an output voltage shift smaller than 1 (mu ) V was successfully obtained. By immobilizing thiol-modified target aptamers onto the nanogold-coated surface of the sensing cantilevers, different concentrations of SEB were detected with a wide detection range of 6-300 ng/mL in buffer, as well as in skim milk. All the experimental results indicate that the piezoresistive cantilever-based aptasensor has sufficient sensitivity to detect food contaminants and might provide an economical platform for on-site detections of different toxicants with the advantages of portability, high sensitivity, and rapid response.