title: A validated LC/MS/MS method for the quantification of pyrrole-2,3,5-tricarboxylic acid (PTCA), a eumelanin specific biomarker, in human skin punch biopsies.
abstract: A novel skin tissue extraction method coupled with liquid chromatography-tandem mass spectrometry (LC/MS/MS) detection was developed and validated for the analysis of endogenous pyrrole-2,3,5-tricarboxylic acid (PTCA), a eumelanin specific biomarker, in human skin punch biopsies. The analyte is extracted from the matrix (2 mm skin punch biopsies) using a simple oxidative degradation procedure. The extract supernatants are evaporated, reconstituted in mobile phase solvent, and injected into the LC/MS/MS system without further derivatization. The chromatographic separation is achieved on a reverse phase high performance liquid chromatography (HPLC) column. The accuracy and precision of the method was determined over the concentration range of 1-1000 ng/mL PTCA from human skin extracts in three validation batch runs. Inter-assay precision (%CV) and accuracy (%R.E.) of the quality control samples were <or=18.5% (at lower limit quality control, LLQC) and <or=5.25%, respectively. The sensitivity and throughput of this assay is significantly improved relative to previously published methods resulting in much smaller tissue requirements and analysis time. This procedure could potentially be used in the investigation of therapies associated with skin pigmentation.
authors.affiliation: Biomarker Implementation Group, Department of Pharmacokinetics, Dynamics & Metabolism, Pfizer Global Research and Development, 2800 Plymouth Road, Ann Arbor, MI 48105, USA. gabriella.szekely-klepser@pfizer.com
authors.forename: Gabriella
authors.initials: G
authors.lastname: Szekely-Klepser
authors.forename: Kimberly
authors.initials: K
authors.lastname: Wade
authors.forename: Dayna
authors.initials: D
authors.lastname: Woolson
authors.forename: Richard
authors.initials: R
authors.lastname: Brown
authors.forename: Scott
authors.initials: S
authors.lastname: Fountain
authors.forename: Erick
authors.initials: E
authors.lastname: Kindt
mesh_terms: D001741:Black or African American; D000818:Animals; D015415:Biomarkers / Q000032:analysis*; D001706:Biopsy / Q000379:methods; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006801:Humans; D013058:Mass Spectrometry / Q000379:methods*; D008543:Melanins / Q000032:analysis*; D051379:Mice; D011758:Pyrroles / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012867:Skin / Q000737:chemistry*; D012880:Skin Pigmentation; D044465:White People
chemical_list: D015415:Biomarkers; D008543:Melanins; D011758:Pyrroles; C041877:eumelanin; C071226:pyrrole-2,3,5-tricarboxylic acid