Caffeine skin delivery

Touitou, E., et al. 1994. Modulation of caffeine skin delivery by carrier design Liposomes versus permeation enhancers. Int J Pharm 103 131. 

Modulation of epidermal lipid biosynthesis has been reported to boost drag delivery. It has also been suggested that it is both the hydrophobic nature of the lipids as well as their tortuous, extracellular localization that are responsible for the restriction in the transport of most molecules across the stratum comeum. The function of this barrier depends on three key lipids cholesterol, fatty acid, or ceramides. Delays of synthesis ceramides in the epidermis have been reported as means of barrier perturbation. Inhibitors of lipid synthesis were used to enhance the trans-A cmaV dehvery of hdocaine or caffeine. Alteration of barrier function was produced by the fatty acid synthesis inhibitor S-(tetradecyloxy)-2-furancarboxylic acid, the cholesterol synthesis inhibitor fluvastatin, or the cholesterol sulfate, which resulted in a further increase in lidocaine absorption (38). The major components of sebaceous lipids in the skin are 45-60% TAGs, 25% wax and sterol esters, 12-15% squalene and 10% free fatty acids (39). Some fatty acids, especially unsaturated fatty acids, are well-known skin penetration enhancers. The addition of PC to dermal dosage forms has been reported to increase percutaneous absorption. Lipid disperse systems (LDSs) containing polar lipids, such as PC and glycosylceramide, are also useful for... 

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