Quantitation of influenza A virus in the presence of extraneous protein using electrochemical impedance spectroscopy

In an attempt to provide an insight into detection of specific viruses in biological samples, we report on quantitation of influenza A virus (IAV) in samples containing large amounts of extraneous bovine serum albumin (BSA), foetal bovine serum (FBS) and hepatitis B virus (HBV) vaccine. Detection was carried out using electrochemical impedance spectroscopy (EIS) with an antibody-neutravidin-thiol architecture immobilized on the surface of an Au electrode. A linear response of the EIS signal was observed for IAV concentrations ranging from 0 to almost 64 ng/mL. However, saturation of the EIS response was recorded for greater concentrations and only a 6% increase in signal occurred when the IAV concentration increased to 128 ng/mL. The limit of detection, determined at 8 ng/mL, remained relatively unaffected by the environment composed of 50 ng/mL of HBV and 12.5% of FBS.