In vitro Release of Ciclopirox Olamine from Different Formulations of Oil in Water Emulsions with Oat Gel

Abstract

Background: Oil-in-water emulsions rely on critical factors like emulsifier composition and quantity, viscosity modifiers and other additives for emulsion stability and efficacy of active substances. [1] Oat gel renowned for its skin-enhancing properties, serves as a multifaceted component in emulsion dispersion, offering stabilization, emulsification, and textural augmentation. [2] Oat-fortified emulsions efficiently alleviate dermatological symptoms. [3] Ciclopirox olamine, a versatile topical agent, effectively treats fungal skin conditions. [4] In vitro release studies are crucial for evaluating its performance in emulsions. The aim: to determine the in vitro release profiles in ciclopirox olamine across various oil in water emulsion formulations with oat gel. Methods: The in vitro study was performed using flow-through cells. Quantitative analysis of released ciclopirox olamine was conducted using ultra-high-performance liquid chromatography. Conducted over 6 hours at 32 ± 0.5 °C, simulating skin surface temperature with cellulose diffusion membranes. Four emulsion formulations with varying emulsifier (10% or 5%) and cetyl alcohol (0% or 5%) content were tested. All other components, including ciclopirox olamine concentration (1%), oat gel (5%), xantan gum (0,3%) and propylene glycol (5%), remained consistent across formulations. Results: After 6 hours, ciclopirox olamine flux varied (0.116 mg/cm² to 0.151 mg/cm²) across emulsion formulations. The highest flux (0.151 mg/cm²) occurred in 0% cetyl alcohol and 5% emulsifiers emulsion, while the lowest, comparable fluxes were in emulsions with 5% cetyl alcohol and 5% emulsifiers (0.116 mg/cm²), 5% cetyl alcohol and 10% emulsifiers (0.118 mg/cm²). Statistical test shows no significant differences (p=0.602, when the level of statistical significance is p < 0.05). Conclusion: While there was no statistical distinction in cyclopirox release among various emulsion formulations, subtle differences were noted. Emulsions with reduced emulsifier and cetyl alcohol content exhibited enhanced in vitro release of cyclopirox olamine, whereas those with elevated emulsifier and cetyl alcohol content demonstrated marginally lower release.