title: Ex vivo cutaneous absorption assessmentof a stabilized ascorbic acid formulation using a microdialysis system.
abstract: BACKGROUND
  Reactive oxygen species generated by ultraviolet light result in photocarcinogenic and photoaging changes in the skin. Antioxidants protect the skin from these insults.
  
  
  OBJECTIVE
  The aim of this study was to determine the ex vivo ascorbic acid penetration and its degradation in the skin after its topical application from an 8% new formulation.
  
  
  METHODS
  Ascorbic acid was applied to human skin fragments. Ascorbic acid and its metabolites were collected by microdialysis and assessed by gas chromatography mass spectrometry.
  
  
  RESULTS
  After topical application of the new formulation, the ascorbic acid level achieved was 8.5% higher than [corrected] times the normal tissue value. This high ascorbic acid dermal concentration remained constant if a topical application was made every 8 h. No degradation of ascorbic acid was detected.
  
  
  CONCLUSIONS
  Ascorbic acid penetrates rapidly after its topical application. The persistent reservoir of ascorbic acid provides an important and attractive photoprotection strategy.
authors.affiliation: Laboratoire d'Ingénierie et Biologie Cutanées et Institut Fédératif de Recherche, Besançon, France.
authors.forename: N
authors.initials: N
authors.lastname: Leveque
authors.forename: P
authors.initials: P
authors.lastname: Muret
authors.forename: S
authors.initials: S
authors.lastname: Makki
authors.forename: S
authors.initials: S
authors.lastname: Mac-Mary
authors.forename: J P
authors.initials: JP
authors.lastname: Kantelip
authors.forename: P
authors.initials: P
authors.lastname: Humbert
mesh_terms: D000287:Administration, Topical; D001205:Ascorbic Acid / Q000378:metabolism* / Q000493:pharmacokinetics; D002626:Chemistry, Pharmaceutical; D005260:Female; D016166:Free Radical Scavengers / Q000378:metabolism* / Q000493:pharmacokinetics; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D017551:Microdialysis; D012869:Skin Absorption
chemical_list: D016166:Free Radical Scavengers; D001205:Ascorbic Acid