MEMS biosensor for parallel and highly sensitive and specific detection of hepatitis

A label-free biosensor array that offers highly sensitive, high-dynamic-range and highly specific detection of Hepatitis A antigen is reported. Sensor array consists of Ni cantilevers with surfaces functionalized with Hepatitis A antibody. Cantilevers are self-actuated at resonance using a single electromagnetic drive coil. Detection of resonance frequency is optical and facilitated by diffraction gratings embedded on cantilevers. All antibody-antigen interactions take place within undiluted bovine serum providing a high background noise due to unspecific molecules. A minimum detection limit of less than 0.1 ng/ml target molecule concentration is demonstrated. A high dynamic range is achieved, which is greater than 1000:1 concentration range. The proposed sensor array is shown to be compatible with most of the requirements of a hand-held biosensor including label-free, robust and real-time measurement with well integrated components.