Bioconjugated Gold Nanoparticle Based SERS Probe for Ultrasensitive Identification of Mosquito-Borne Viruses Using Raman Fingerprinting

Dengue virus (DENY) and West Nile virus (WNV) are two well-documented mosquito-borne flaviviruses that cause significant health problems worldwide. Driven by this need, we have developed a bioconjugated gold nanoparticle (AuNP) based surface enhanced Raman spectroscopy (SERS) probe for the detection of both DENY and WNV. Reported data demonstrate that the antiflavivirus 4G2 antibody conjugated gold nanoparticle (GNP) SERS probe can be used as a Raman fingerprint for the ultrasensitive detection of DENY and WNV selectively. Experimental data show that, due to the plasmon coupling in nanoassembly, antibody conjugated GNP based SERS is able to detect as low as 10 plaque-forming units (PFU)/mL of DENV-2 and WNV, which is comparable with the sensitivity of quantitative PCR based assays. Selectivity of our probe was validated using another mosquito-borne chikungunya virus (CHIKV) as a negative control. Experimental data demonstrate that the huge enhancement of SERS intensity is mainly due to strong electric field enhancement, which has been confirmed by a finite-difference time-domain (FDTD) simulation. Reported FDTD simulation data indicate the SERS enhancement factor can be more than 104 times, due to the assembled structure. Reported results suggest that bioconjugated AuNP-4G2 based SERS probes have great potential to be used to screen viral particles in clinical and research based laboratories.