Investigation of inorganic cluster–surfactant flocculants for virion sequestration and removal from aqueous media

Abstract Anionic polyoxometalates or cationic aluminum clusters when combined with a surfactant of an opposite charge form hydrophobic precipitates that are approximately lamellar with alternating layers of interdigitated surfactant tails and inorganic clusters. The charged surfactant heads are associated with the inorganic cluster layers. When these phases self-assemble and precipitate from aqueous media spiked with a virus titer, either bovine enterovirus (BEV) or influenza A, the precipitates effectively sequester the virions via an enmeshment process. These studies were done via precipitation and filtration of the cluster–surfactant floc in the presence of the virus, followed by reverse transcriptase polymerase chain reaction ( r RT-PCR) analysis of the filtrate. Efficacy of these cluster–surfactant phases for virion sequestration is variable as a function of their solubility, the size of colloid formed in solution, and their degree of long-range order. Generally less soluble, poorly ordered precipitates that form the largest colloids are the most effective virion sequestering media. Cluster–surfactant phases were characterized in solution by nuclear magnetic resonance (NMR) and dynamic light scattering (DLS); and in the solid-state by powder X-ray diffraction and solid-state magic angle spinning (MAS) NMR.