A “Turn-on” fluorescent bioprobe with aggregation-induced emission characteristics for detection of influenza virus-specific hemagglutinin protein

Four hexaphenyl-butadiene pyridine salt derivatives (HPB-Xs) with aggregation-induced emission (AIE) characteristics were designed and synthesized. After comprehensive comparison of the four compounds, HPB-I was selected for protein detection. The good-linear response of HPB-I to hemagglutinin 5 protein (H5) on surface of influenza virus were realized with the characteristics of real-time, high-selective, and sensitive in a wide range of H5 concentration. The limit of detection (LOD) was as low as 179.5 ng/mL (3.04 nM) in throat swaps. HPB-I also achieved colorimetric detection for H5 by naked eyes. The simulation calculations based on molecular docking revealed that HPB-I could well combine with the top-cavity of H5 and achieved single-molecule-limited “turn-on” fluorescence signal. This study is a significant step in the development of a low-cost influenza test at the point of pursuing a new strategy for the molecular design of antiviral drugs or virus staining and tracing.