On-site Screening of Avian Influenza Virus (AIV) by Polystyrene Microfluidic Chip Immunoassay

In this study, AIV (AIV) Ag of A type with viral nucleoprotein (NP), which covers all AIV subtypes, including high-pathogenic AIV, was demonstrated by the novel format of polystyrene microfluidic chip ELISA. In micro-channels of chip instead of conventional 96-well microtiter plates, a double-antibody sandwich ELISA (DAS-ELISA) was developed, in which rabbit Ab, mouse nuclear protein (NP) mAb and horseradish peroxidaseconjugated goat anti-mouse immunoglobulin were used as coating, primary and secondary antibodies, respectively. Recombine Ag of AIV was prepared as positive control to ensure the on-site test safety. With TMB as substrate, AIV Ag could distinctly be judged by comparing colors of sample detection windows with that of the negative control in micro-channels, a preliminary result was obtained in accordance with conventional ELISA while total analytical time were within 1 h. The on-chip DAS-ELISA was well applicable to rapid and real-time screening of AIV. The sensitivity could be further improved by optimization experiments.