Iodophors are effective germicidal agents that have prolonged
antiseptic activity in contaminated
wounds. A nontoxic
surfactant,
Pluronic F-68, has been used to formulate a safe and effective iodophor. The parameters necessary to regulate the activity of the iodophor were studied to develop a potent, yet safe bactericidal
solution for use in human subjects. The parameters found to be most important were the pH of the
solution and the concentration of
sodium iodide. Lowering the pH of
iodophors increased their stability and
antiseptic activity. The free
iodine in iodophor solutions prepared with a low pH is predominantly the highly biocidal diatomic
iodine (I2). The concentration of
iodide regulated the equilbrium of the dissolved
iodine between its free and complexed form. Increasing the concentration of
iodide in the iodophor lowered the amount of free
iodine in
solution and enhanced the concentration of the complexed
iodide. It is the level of free
iodine in an iodophor that determines its
antiseptic activity. Low levels of free
iodine yielded
iodophors that had a slow bacterial kill rate but a prolonged duration of action. Manipulation of these variables permitted the generation of
iodophors that varied considerably in their kill rates of bacteria and their duration of antibacterial activity.
Iodophors tested in this study demonstrated a distinct superiority to noncomplexed
iodine solutions (tincture and aqueous
iodine solutions) as
wound and skin cleansers.