Development of double-generation gold nanoparticle chip-based dengue virus detection system combining fluorescence turn-on probes.

A sensing platform, combined amino acid labeling kit and a double-generation gold nanoparticle (DG-AuNP) chip, was designed to prove the existence of weak but crucial binding between the DV (dengue virus) and its CLEC5A receptor. At first, we have designed a kit combining the novel fluorescence turn-on sensors for lysine, arginine and cysteine amino acids. Advantages of this kit are that emission on-off switching can increase the signal-to-noise ratio and the virus must be fluorescently labelled with sufficient numbers of fluorophores because the lysine, arginine and cysteine residues of viral proteins are labelled simultaneously. Consequently, this kit can be used to light-on single DV spot both in solution and in cell under fluorescence microscopy. Second, the labeling kit was used to examine the DV binding to the CLEC5A-coated DG-AuNP chip. Based on our study, the double-generation gold nanoparticle construction of chip can support more coating areas for receptor CLEC5A and then, support more binding opportunities for DV. Meanwhile, the grooves between nanohemispheres will provide the extra driving force for DV stacking. We try to give a proof that this sensing platform is very useful for detection of weak binding mechanism.