title: Validation of a microdialysis-gas chromatographic-mass spectrometric method to assess 8-methoxypsoralen in psoriatic patient dermis.
abstract: 8-Methoxypsoralen (8-MOP) is currently used in PUVA therapy (psoralen+UVA) to treat dermatological diseases such as psoriasis, vitiligo and atopic dermatitis. The aim of this work was to validate a method for collecting 8-MOP from patient dermis by a non invasive technique, microdialysis, and then to assess this molecule by gas chromatography-mass spectrometry (GC-MS). 5-Methoxypsoralen (5-MOP) was used as an internal standard. The calibration curve demonstrated a linear relationship between the peak areas of 8-MOP and 5-MOP over a wide range of 8-MOP concentrations (0.9-100 ng/ml). Within- and between-run precisions were measured, using four different 8-MOP concentrations, which varied from 98.0 to 102.0% and from 98.5 to 101.8%, respectively. The limits of detection and quantification were 0.29 and 0.52 ng/ml, respectively. The method was validated and then applied to determine the pharmacokinetic of 8-MOP in ten psoriatic patient dermis, after oral intake of this drug. The results demonstrated that the association of microdialysis with the GC-MS method was an efficient procedure to collect and assess 8-MOP in human dermis, in vivo.
authors.affiliation: Laboratoire d'Ingénierie et de Biologie Cutanées, Faculté de Médecine et de Pharmacie, Hôpital Saint Jacques, Place Saint Jacques, 25030, Cedex, Besançon, France.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Leveque
authors.forename: Patrice
authors.initials: P
authors.lastname: Muret
authors.forename: Sophie
authors.initials: S
authors.lastname: Mary
authors.forename: Michel
authors.initials: M
authors.lastname: Bérard
authors.forename: Safwat
authors.initials: S
authors.lastname: Makki
authors.forename: Jean
authors.initials: J
authors.lastname: Pierre Kantelip
authors.forename: Philippe
authors.initials: P
authors.lastname: Humbert
mesh_terms: D000328:Adult; D000368:Aged; D002138:Calibration; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006801:Humans; D008297:Male; D008730:Methoxsalen / Q000378:metabolism*; D017551:Microdialysis; D008875:Middle Aged; D011565:Psoriasis / Q000378:metabolism*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012867:Skin / Q000378:metabolism*
chemical_list: D008730:Methoxsalen