Analysis of the combined effect of 1-menthol and ethanol as skin permeation enhancers based on a two-layer skin model

摘要: The combined effects of 1-menthol and ethanol as a skin permeation enhancer were evaluated with two equations describing the permeability coefficient through full-thickness (PFT) skin/vehicle concentration ratio (CFT/CV) drugs function their octanol/vehicle partition (KOV). A two-layer model was applied for skin, which consists stratum corneum (SC) lipid porous pathways viable epidermis dermis (ED). contain one variable (KOV) nine coefficients, six (three diffusion porosity SC, terms linear free energy relationship) considered different, dependent on drug vehicle. In vitro four (morphine hydrochloride, atenolol, nifedipine, vinpocetine) determined using excised hairless rat aqueous vehicles (water, 5% 1-menthol, 40% ethanol, l-menthol–40% ethanol) to measure each PFT. Drug concentrations in also measured obtain CFT/CV. nonlinear least-squares method employed determine coefficients experimentally obtained PFT addition water increased pore whereas solubility vehicle, decreased polarity, contribution pathway whole-skin permeation.