Development and validation of a high-performance liquid chromatographic method for the determination of cyproterone acetate in human skin.
In the framework of a preliminary study on the transdermal penetration of cyproterone acetate (CPA), a simple and rapid procedure involving an extraction step coupled to a HPLC-UV determination has been developed for the separation and quantification of CPA in the two main skin layers-epidermis and dermis-after local application. The separation of epidermis and dermis layers was carefully carried out by means of a sharp spatula after skin immersion in heated water at 65 degrees C. The two skin layers were then treated separately according to the same process: (1) sample homogenization by vibration after freezing with liquid nitrogen in a Mikro-Dismembrator; (2) CPA extraction with methanol after addition of the internal standard (betamethasone dipropionate); (3) centrifugation; (4) evaporation of a supernatant aliquot; (5) dissolution of the dry residue in methanol and addition of water; (6) centrifugation; (7) injection of a supernatant aliquot into the HPLC system. The separation was achieved on octadecylsilica stationary phase using a mobile phase consisting in a mixture of acetonitrile and water (40:60 (v/v)). The method was then validated using a new approach based on accuracy profiles over a CPA concentration range from 33 to 667 ng/ml for each skin layer. Finally, the method was successfully applied to the determination of CPA to several skin samples after topical application of different gel formulations containing CPA.
Henry de Hassonville
Sandrine
S
Department of Pharmaceutical Technology, Institute of Pharmacy, University of Liège, CHU, B36, Liège B-4000, Belgium.
Chiap
Patrice
P
Liégeois
Jean-François
JF
Evrard
Brigitte
B
Delattre
Luc
L
Crommen
Jacques
J
Piel
Géraldine
G
Hubert
Philippe
P
D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D017373:Cyproterone Acetate / Q000032:analysis* / Q000493:pharmacokinetics; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012867:Skin / Q000737:chemistry* / Q000378:metabolism; D012869:Skin Absorption; D013048:Specimen Handling
D017373:Cyproterone Acetate