Fig. 1.

Schematic diagram of FBAR biosensor to detect MUC1 biomolecules. a The basic configuration of the ZnO-based FBAR. b Streptavidin was self-assembled on the active area of the FBAR as the sensitive layer. c In the absence of MUC1, the biotin is shielded in the AuNPs-MUC1 ampters chelates and cannot be captured by the streptavindin immobilized on FBAR. d When the target MUC1 is present, the immune binding between MUC1 and the thiol-biotin modified-aptamer reacts and makes the biotin exposed, as a result, the biotin can be captured by the streptavindin immobilized on FBAR