Integrated capture and spectroscopic detection of viruses in an aqueous environment

A new approach to virus detection in an aqueous environment has been developed using the electrophoretic deposition of protein and viruses on a charged surface for in situ infrared characterization and identification. In this study, a potential was applied across a germanium ATR crystal, which acted as the anode, and an indium tin oxide (ITO) plate, which acted as the cathode in the electrodeposition setup. Sample aqueous solutions were placed between the germanium and the ITO with different concentrations of the protein bovine serum albumin (BSA) and the virus MS2, in tap water. The pH of the tap water was above the isoelectric point of the virus and the protein, resulting in a net negative charge for both. The negatively charged protein and virus were then driven to the surface of the positively charged germanium ATR crystal, once a potential was applied to the system. FTIR/ATR was used before and throughout electrodeposition to enable the in situ observation of the deposition with time. In this study, we evaluate the capture efficiency, compared to control experiments with no applied voltage, and the feasibility of using this approach for the collection and quantification of proteins and viruses from water samples. This technique resulted in the successful deposition of BSA, and MS2 with an applied voltage of only 1.1V. Furthermore, based on the analysis of the ATR spectra, distinct spectral features were identified for the protein and virus showing the potential for identification and characterization of biological molecules in an aqueous environment.