
Ex vivo Skin Permeation of Betulin from Water-in-Oil Foams
Author(s) -
Anna Färber,
Rolf Daniels
Publication year - 2016
Publication title -
skin pharmacology and physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.703
H-Index - 74
eISSN - 1660-5535
pISSN - 1660-5527
DOI - 10.1159/000448689
Subject(s) - permeation , terpene , chromatography , chemistry , stratum corneum , solvent , materials science , membrane , organic chemistry , medicine , biochemistry , pathology
Triterpenes of the outer bark of birch are known to improve wound healing. An oleogel with these triterpenes as active principle is approved by the European Medicines Agency. As foams can be applied without touching the skin, they might be an advantageous application form. A comparable wound-healing effect can be expected when the permeation flux of the triterpenes from different types of formulations, namely oleogels, water-in-oil emulsions and water-in-oil foams, is similar. The tested formulations were based on three lipids (medium-chain trigylcerides, sunflower oil and paraffin) which differ in their polarity and solvent power for the triterpenes. Infinite dose permeation experiments were performed using porcine skin which was injured by either tape stripping or skin grafting. The results showed that steady-state permeation flux and lag time depend clearly on the depth of the skin lesion. Moreover, it was substantially affected by the lipid used as basis for the different formulations. In contrast, the different formulation types showed a comparable permeation behaviour leading to the conclusion that all formulation types can be used alike for the treatment of wounds, and the results that have already been obtained with oleogels can be directly translated to the foam with its superior use properties.