Immunoassay using a biofunctionnalized alumina-coated capacitive biosensor: towards a microfluidic detection of the H5N1 Influenza virus

Influenza A viruses cause annual epidemics and occasional pandemics that spread worldwide. The nucleoprotein is essential for the survival of this virus and is thus well-conserved. We developed a quantitative electronic biosensor displaying a protein recognition thanks to the covalent grafting of anti-nucleoprotein antibodies. The detection device lies on interdigitated array microelectrodes (IDAM), covered with alumina (Al2O3) to protect the underlying aluminum and enhance the electrical coupling. As the dimensions of the IDAM can determine the sensitivity of the sensor, we processed 4 structures with varying electrode widths and spacings in the same silicon chip and assessed their individual performance. The sensing area of each sensor is 200*200 µm2 and the overall chip-size is 3*3 mm2. The sensor is mounted in a DIL-16-package partially encapsulated by resin.