Removal of viruscide agents by using styrenic resins

Strong and weak anionic polystyrene/divinylbenzene ion exchange resins were investigated both as iodophores and as iodine/iodide ion removal agents in blood disinfection applications. Resin-iodine complexes were prepared, but there was no significant iodine release observed in either distilled water or isotonic saline solution. However, all ion-exchange resin were able to remove almost quantitatively both iodine and iodide ions from water solutions. Cross-linked styrene/divinylbenzene resins are excellent polyaromatic viruscide adsorbents, although their hydrophobicity is responsible for poor wettability in physiologi-cal fluids. Surface modification with hydrophilic reagents appeared a promising strategy to overcome this drawback. A Merrifield-type chloromethylated resin and a highly cross-linked mesoporous resin (Lewatit 1064) with a large surface area and content of unreacted vinyl groups were selected as starting materials. The Merrifield resin was modified by the reaction of the pendant chloromethyl groups with triethyleneglycol, tetraethyleneglycol and â -cyclodextrin. The conversion of Lewatit double bonds into hydrophilic moieties was attempted by the radical grafting of N-vinyl-2-pyrrolidinone (NVP), maleic anhydride (MAn), 2-hydroxyethyl methacrylate, acrylamide (AAm) and different poly(ethyleneglycol) (PEG) methacrylates. The addition of 2-mer-captoethanol (2ME) and epoxidation were also investigated. The modified Merrifield resins demonstrated very low efficiency in acridine viruscide uptake, in spite of the large increase in both wettability and water uptake. On the other hand, all modified Lewatit samples removed rapidly and almost quantitatively the viruscide from aqueous solutions, although only a few samples resulted in being very hydrophilic. In all cases, hydrophilicity and viruscide adsorbing capacity were maintained after heating at 180 degrees C to simulate pyrogen elimination.