Capture and release of viruses using amino-functionalized silica particles

A new virus capture/release strategy for the concentration of viral particles in water is reported. The method is an improvement upon traditional approaches that rely exclusively upon electrostatic attractions between a charged substrate and charged viral particles, which can only be reversed under extremely acidic or alkaline conditions to effect surface charge reversal and subsequent release of captured viruses. This method utilizes negatively charged silica beads functionalized with amino groups using defined length spacer molecules to yield particles with a surface density optimized for efficient virus capture. Following capture, viruses can be released using soluble proteins or amino acid-based alkaline eluents. Virus recoveries are a function of the composition of elution solution used. The zeta potentials of amino-functionalized silica particles were analyzed and used to optimize the density of functionalized groups and the charge behavior of the functionalized silica surfaces. Raman spectrometry was used for the characterization of functionalized silica beads. This method is expected to apply in the analysis of viruses.