Determination of Staphylococcus Enterotoxin B Using a Flexible Aptamer-Based Biosensor

We demonstrate a fully flexible micromachined cantilever-based aptasensor for sensitive and specific sensing of staphylococcus enterotoxin B (SEB). The proposed flexible cantilever was fabricated using parylene-C as surface passivation layers and poly(3,4-ethylenedioxythiophene)/ polystyrene sulfonate (PEDOT:PSS) as strain gauge for characterization of resistance. A spring constant of prepared cantilever was measured to be 12 nN/ $\mu \text{m}$ together with a deflection sensitivity of $1.42\times 10^{-{3}}/\mu \text{m}$ . With assembled 78-mer 5’-biotinylated aptamers on the sensing cantilever surface, the fully flexible aptasensor is capable of specific recognition SEB with a detection limit of 0.3 ng/mL. To evaluate the applicability of the proposed aptasensor, detections on raw milk spiked with SEB were implemented. The comparison indicates that the prepared aptasensor could be qualified for SEB recognition in food contaminants detections, and the fully flexible cantilever-based sensors have tremendous potential for applications in food safety evaluation.