In this talk, the label-free detection mechanisms of those tumor DNA as welll as nanoscale materials based on resonance frequency are presented. The detection mechanism is based on the measurement of the resonance frequency shift arisen from the binding of the target materials on DNA immobilized resonator. We are able to detect circulating tumor DNA and nanotoxic materials such as SWNT, silver ion and ZnO wire et al specificially. This work shows the potential of DNA immobilized resonator as the screening tool of circulating tumor DNA and nanotoxic materials.