free iodine, slowly liberated from the povidone-iodine (pvp-i) complex in solution, kills eukaryotic or prokaryotic cells through iodination of lipids and oxidation of cytoplasmic and membrane compounds. this agent exhibits a broad range of microbicidal activity against bacteria, fungi, protozoa, and viruses. slow release of iodine from the pvp-i complex in solution minimizes iodine toxicity towards mammalian cells.