title: A physico-chemical study of PVP-I solutions leading to the reformulation of 'Betadine' preparations (5% PVP-I).
abstract: Detailed study of various povidone-iodine (PVP-I) and Lugol's solutions has demonstrated that bactericidal potency, as well as skin sensitivity, correlates directly with the mass of elemental iodine that can be extracted by the immiscible solvent, n-heptane. This study, using various extractant volume ratios, revealed that the concentration of I2 that can be extracted can be described by two exponential equations of the form Y = a e-kv. Where Y is the concentration of I2 extracted, v is the volume ratio of solvent used and a and k are constants. At low volume ratios, only the most easily extracted I2 is removed corresponding to the replaceable free I2 in the iodophor solution; whereas at higher extractant volume ratios, only the true reservoir I2 is involved. From the two exponential extraction equations can be described two new potency terms that define bactericidal potency and safety. The significance of the two terms, "relative potency factor' (RPF) and "maximum potency factor' (MPF) are described in detail with their relevance to a new "Betadine' solution containing 5% PVP-I.
authors.forename: W
authors.initials: W
authors.lastname: Pollack
authors.forename: O
authors.initials: O
authors.lastname: Iny
mesh_terms: D000891:Anti-Infective Agents, Local / Q000494:pharmacology*; D001407:Bacillus / Q000502:physiology; D002626:Chemistry, Pharmaceutical; D006801:Humans; D007454:Iodides / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D011205:Povidone / Q000031:analogs & derivatives*; D011206:Povidone-Iodine / Q000494:pharmacology*; D012867:Skin / Q000187:drug effects; D012996:Solutions; D013171:Spores, Bacterial / Q000187:drug effects; D013211:Staphylococcus aureus / Q000502:physiology
chemical_list: D000891:Anti-Infective Agents, Local; D007454:Iodides; D012996:Solutions; D011206:Povidone-Iodine; D011205:Povidone; C010389:Lugol's solution