In Vitro Release of Zinc Pyrithione from a Shampoo Base and the Effects of Various Additives on Its Release Rate

The study investigated the in-vitro release of zinc pyrithione from a shampoo base and the effects of various additives on its release rate. The shampoo formulation included an anionic detergent, an amide, and thickening agents, with additives like ethanol, DMSO, polyethylene glycol-400, propylene glycol, and urea at different concentrations. Experiments at 37°C showed that additives generally increased the release of zinc pyrithione, with ethanol and propylene glycol yielding the highest release rates. The release rank order was ethanol > DMSO > urea > polyethylene glycol-400 > propylene glycol > commercial products.