New Water Disinfectant: an Insoluble Quaternary Ammonium Resin-Triiodide Combination that Releases Bactericide on Demand

Strongly basic anion-exchange resins form stable, water-insoluble combinations with triiodide ions. The combinations have remarkable antibacterial properties: 3.0 × 105 Escherichia coli cells per ml were killed when passed through a 3.8-g column of commercially available resin treated with triiodide (volume 4 ml after treatment). In an attempt to deplete the resin-triiodide complex, 1.14 × 109 E. coli cells in 15 liters were passed through the column with no significant loss of effectiveness. The antibacterial capabilities of the resin-triiodide columns ranged from 106 Salmonella typhimurium per ml to 1.1 × 104 Streptococcus faecalis per ml.Staphylococcus aureus andPseudomonas aeruginosa were also tested and killed at concentrations of 1.8 × 104 and 1.3 × 105 per ml, respectively. The cells were not filtered from the water. They emerged from the column in nonviable form. This was demonstrated by using14 C-labeled bacteria. The irreversible nature of the antibacterial action was revealed when attempts to wash the damaged cells did not restore viability.