Plasmonic/magnetic molybdenum trioxide and graphitic carbon nitride quantum dots-based fluoroimmunosensing system for...

A novel magnetic/plasmonic-assisted fluoro-immunoassay system is developed for the detection of influenza virus using magnetic-derivatized plasmonic molybdenum trioxide quantum dots (MP-MoO₃ QDs) as the plasmonic/magnetic agent and fluorescent graphitic carbon nitride quantum dots (gCNQDs) as the monitoring probe. Specific antibody against influenza A virus was conjugated onto the surface of MP-MoO₃ QDs and gCNQDs, respectively. In the presence of influenza A virus (as the test virus), a core-satellite immunocomplex is formed between the antibody-conjugated nanomaterials (Ab-MP-MoO₃ QDs and Ab-gCNQDs) and their interaction resulted in the modulation and gradual enhancement of the fluorescence intensity of the detection probe with the influenza virus concentration-dependent increase. In addition, PL change without influenza A virus was not observed. Limits of detection of 0.25 and 0.9 pg/mL were achieved for Influenza virus A/New Caledonia (20/99/IVR/116) (H1N1) detection in deionized water and human serum, respectively. Clinically isolated influenza virus A/Yokohama (110/2009) (H3N2) was detected in the range of 45 - 25,000 PFU/mL, with a limit of detection ca 45 PFU/mL (as opposed to a minimum of 5000 PFU/mL for a commercial test kit). This developed biosensor provides a robust, sensitive as well as a selective platform for influenza virus detection.