Construction of Effective Receptor for Recognition of Avian Influenza H5N1 Protein HA1 by Assembly of Monohead Glycolipids on Polydiacetylene Vesicle Surface

Fast and sensitive detection of epidemic virus is of the utmost importance for human being in nowadays. Various biosensors have been designed for this goal based on conjugation event between host cell glycolipids and invading virus. However, multihead glycolipids analogous to native receptors on cell surface are known to be very difficult to mimic because of the complexity of chemical synthesis. Here, we developed a new approach where two types of monohead glycolipids, active sialic acid-beta-glucoside (G1) and inactive lactose-beta-glucoside (G2), are embedded onto the surface of a polydiacetylene (PDA) vesicle to mimic native glycolipids on the cell surface. Vesicles prepared in this manner show good selectivity with a 10 ng/mL detection limit and 5 min response time to Hemagglutinin (HA1), which is more sensitive than any HA1 biosensors ever known. Moreover, in the formation of color-changeable vesicles, a very strong synergistic effect between G1 and G2 has been found, offering a novel strategy to construct effective biosensor receptors, as well as a new way to study the surface combination effect that is potentially important to the immunology study of epidemic disease.