Bianalyte mass detection with a single resonant microcantilever

Mass-loading detection of multiple kinds of analyte with a single resonant microcantilever is proposed and experimentally validated. By exciting the cantilever in different resonance modes and adsorbing the different analytes at different locations of the cantilever, the specific mass of either kind of analyte can be independently detected. The proposed micromechanical resonant cantilever sensor is designed and fabricated using silicon micromachining techniques. Used as simulant adsorbates, Au and Cr thin films are selectively implemented on the cantilever to verify the bianalyte detecting function. The testing results are consistent with the theoretical analysis, with the detection error being an order of magnitude lower than the analyzed mass.