Challenge
– Water-soluble active ingredients are not able to reach the deeper skin layers or at all only slightly due to the skin barrier properties (protection against dehydration).
– Active substances with high molecular weights, such as proteins, are too big to pass the stratum corneum and to reach the viable skin area. Therefore collagen or hyaluronic acid cannot build up an effective depot in the dermis.
– Poorly soluble active substances cannot be dissolved in effective amounts in the formulation and therefore do not end up at their target sides.