We have demonstrated high-sensitivity detection of bacteria using an array of bulk micromachined resonant cantilevers. The biological sensor is a micromechanical oscillator that consists of an array of silicon-nitride cantilevers with an immobilized antibody layer on the surface of the resonator. Measured resonant frequency shift as a function of the additional cell loading was observed and correlated to the mass of the specifically bound Escherichia coli O157:H7 cells. Deposition and subsequent detection of E. coli cells was achieved under ambient conditions.

Mechanical resonant immunospecific biological detector