KINETIC-ANALYSIS OF VIRUS ADSORPTION AND INACTIVATION IN BATCH EXPERIMENTS

The mobility and ecology of viruses in natural environments is strongl y influenced by the adsorption of virus particles to sand or soil surf aces. This binding process is frequently studied by conducting batch e xperiments in which fluid suspensions of virus particles are contacted with the adsorbent of interest. In this report, a simple first-order kinetic theory is presented which accounts for many of the complicated interactions that can occur when viruses contact an adsorbent in a ba tch system. Closed-form solutions and numerical simulations of the mod el indicate that four classes of virus-surface interactions can be ide ntified, including quasi-equilibrium adsorption, quasi-equilibrium ads orption with surface sinks, quasi-equilibrium adsorption with reduced inactivation, and direct irreversible adsorption. Based on these resul ts, a new experimental approach for studying virus-surface interaction s is proposed and tested using a model system consisting of bacterioph age lambda and Ottawa sand. Fluid samples were collected from sand-con taining and sand-free virus suspensions over the course of 5-6 days an d analyzed for plaque forming units (PFU). These experiments were repe ated using three different pH values and six different electrolyte com positions. Nondimensionalization of the PFU data from the sand-free su spension collapsed all of the data onto a single fine, as predicted by the kinetic model. When plotted in a nondimensional format, data from the sand-containing suspensions exhibited behavior which could readil y be interpreted within the context of the kinetic model. These result s suggest that the proposed approach offers a powerful alternative to conventional methods for studying virus adsorption at the solid-liquid interface, and for predicting the potential mobility and fate of viru ses in porous media.