Self Thermal Elimination of Nanomechanics-Based Biosensor Using a Single Free-Standing Piezoresistive Microcantilever

A compact piezoresistive microcantilever platform integrated by MEMS technique provides a convenient and reliable approach for biochemical detection. In contrast to the conventional double free-standing piezoresistive cantilever beams of heterogeneous sensing surfaces, a single free-standing piezoresistive microcantilever sensor was first proposed with the elimination of interference of chemical effect. The single beam piezoresistive sensor which is temperature-sensitive was well controlled within +/- 0.2 degrees C by introducing the novel method of self elimination of thermal effect. This new approach maintains device compactness with no additional use of bulky temperature-controlled apparatus, and significantly reduces noises of temperature coefficient of resistance (TCR) and bimorph effect. The C-reactive protein (CRP) detection of the microcantilever biosensor with self elimination of thermal effect was verified with the concentration of 100 mu g/mL in a room-temperature environment.