Gold nanocubes based optical detection of HIV-1 DNA via surface enhanced Raman spectroscopy

Optical detection of HIV-1 DNA with surface enhanced Raman spectroscopy (SERS) is a quick and versatile method, having great potential in screening and characterization of HIV-1 virus particle. We have synthesized and applied novel gold nanocubes (AuNCs) for signal enhancement of SERS to study HIV-1 DNA strands by taking into account the specific vibrational bands of functional groups. Raman peaks at 562 cm^-1, 800 cm^-1, 1094 cm^-1 were observed in both Human Random Control DNA and HIV-1 DNA, while three new peaks were detected in infected DNA at 421 cm^-1, 1069 cm^-1 and 1254 cm^-1. Raman bands in case of AuNCs coated HIV-1 DNA molecules were observed with enhanced intensity values as compared to the silver nanoparticles-based SERS substrate. In case of silver nanoparticles (AgNPs) conjugate DNA, we get all signatures of HIV-1 virus at almost the same position with peak distortions, peak alterations and intensities reductions. We overall molecularly observed HIV-1 infected DNA and Human Random Control DNA, with high sensitivity and selectivity using highly sensitive and stable AuNCs in SERS. This technique can be utilized to identify molecular structures and chemical identification of biomacromolecules which can further be investigated as biomarkers for the screening of whole-body HIV-1 virus particles.