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

• Published in: Journal of chromatography. B, Analytical technologies in the biomedical and life sciences Vol. 826; no. 1; pp. 31 - 40
• Main Authors: Szekely-Klepser, Gabriella, Wade, Kimberly, Woolson, Dayna, Brown, Richard, Fountain, Scott, Kindt, Erick
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 05-11-2005; Elsevier Science
• Subjects: African Americans; Analysis; Analytical, structural and metabolic biochemistry; Animals; Biological and medical sciences; Biomarker; Biomarkers - analysis; Biopsy - methods; Chromatography, High Pressure Liquid - methods; Eumelanin; European Continental Ancestry Group; Fundamental and applied biological sciences. Psychology; General pharmacology; Human skin; Humans; LC/MS/MS; Mass spectrometry; Mass Spectrometry - methods; Medical sciences; Melanin; Melanins - analysis; Mice; Pharmacology. Drug treatments; Pigmentation; PTCA; Pyrrole-2,3,5-tricarboxylic acid; Pyrroles - analysis; Reproducibility of Results; Sensitivity and Specificity; Skin - chemistry; Skin Pigmentation; Biomarker; LC/MS/MS; PTCA; Human skin; Mass spectrometry; Pigmentation; Eumelanin; Melanin; Pyrrole-2,3,5-tricarboxylic acid; Human; Human skin: Pigmentation; Biological marker; Liquid chromatography; Spectrometry; Investigation method; Skin
• ISSN: 1570-0232; 1873-376X
• DOI: 10.1016/j.jchromb.2005.08.002

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 ≤18.5% (at lower limit quality control, LLQC) and ≤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.