Skin penetration of 5-aminolevulinc acid in vitro

摘要

5-Aminolevulinic aicd (ALA), the metabolic precursor to protoporphyrin IX in the bisoynthetic pathway for heme, is frequently applied topically in photodynamic therapy of selected cutaneous diseases, including basal cell carcinomas, squamous cell carcinomas, solar and actinic keratosis, Bowen's disease.~1,2 The ALA molecule is hydrophilic and does not penetrate through intact skin easily. However, cutaneous diseases are frequently associated with elevated transpidermal water loss (TEWL) and impaired permeability barrier function. The objective of the study was to investigate the effect of permeability barrier disruption, concentration and pH on the skin penetration of ALA applying in vitro methodology.