Improved method for analysis of cysteinyldopa in human serum
2004 (English)In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, Vol. 64, no 6, 559-564 p.Article in journal (Refereed) Published
5-S-L-Cysteinyl-L-dopa is a well-known pigment intermediate and analysis of its serum concentration is well suited for evaluation of treatment and follow-up of stage III and IV malignant melanoma. A simplified analytical method is described using organic extraction followed by clean-up on a boronate gel to capture the compound containing vicinal hydroxyls. Weak acid solution elutes the 5-S-cysteinyldopa suitable for high-performance liquid chromatography (HPLC). The absolute recoveries of cysteinyldopa and its diastereomer 5-S-D-cysteinyl-L-dopa (used as an internal standard) were 81.5±2.8% and 81.3±2.7%, respectively, and use of the internal standard for the whole procedure gave an analytical recovery of 101±0.8%. The limit of quantitation was 1.5 nmol/L and the imprecision of the method was < 5.0% over the analytical range 1.5-500 nmol/L. The method is cheap and easy to perform and compares well with other described techniques. The use of the method is illustrated by results obtained during treatment of a patient with metastatic malignant melanoma.
Place, publisher, year, edition, pages
2004. Vol. 64, no 6, 559-564 p.
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-23708DOI: 10.1080/00365510410007026Local ID: 3211OAI: oai:DiVA.org:liu-23708DiVA: diva2:244023