A new modified Edman procedure for analysis of N-terminal valine adducts in hemoglobin by LC-MS/MS
2010 (English)In: Journal of chromatography. B, ISSN 1570-0232, E-ISSN 1873-376X, Vol. 878, no 27, 2483-2490 p.Article in journal (Refereed) Published
A rapid and sensitive method using liquid chromatography-tandem mass spectrometry (LC-MS/MS) for simultaneous determination of adducts from acrylamide, glycidamide and ethylene oxide to N-terminal valines in hemoglobin (Hb) was developed. This new procedure is based on the same principles as the N-alkyl Edman procedure for analysis of adducts from electrophilic agents to N-terminal valines in Hb. The N-substituted valines can be detached, enriched and measured selectively as thiohydantoins by the use of an Edman reagent, in this case fluorescein isothiocyanate (FITC). This procedure is denoted as the "adduct FIRE procedure" as the FITC reagent is used for measurement of adducts ((R) under bar) formed from electrophilic compounds with a modified Edman procedure. In this study, fluorescein thiohydantoin (FTH) analytes of N-substituted valines from acrylamicle, glycidamide and ethylene oxide, as well as their corresponding hepta- and tri-deuterium-substituted analogues, were synthesized. These analytes (n = 8) were then characterized by LC-MS/MS (ESI, positive ion mode) and obtained product ions were interpreted. A considerable work with optimization of the FIRE procedure (TM), resulted in a procedure in which low background levels of the studied adducts could be measured from 250 mu L lyzed whole blood samples (human non-smokers). The analytes were enriched and purified with solid phase extraction columns and analyzed by LC-MS/MS with LOQ clown to 1 pmol adduct/g Hb. Compared to other procedures for determination of N-terminal Hb adducts, the introduction of FITC has led to a simplified procedure, where whole blood also can be used, giving new opportunities and reduced hand on time with increased sample throughput.
Place, publisher, year, edition, pages
2010. Vol. 878, no 27, 2483-2490 p.
Hemoglobin adducts, Acrylamide, Ethylene oxide, Modified Edman, Adduct FIRE procedure, LC-MS/MS
Research subject Environmental Chemistry
IdentifiersURN: urn:nbn:se:su:diva-51442DOI: 10.1016/j.jchromb.2010.03.034ISI: 000283410200004OAI: oai:DiVA.org:su-51442DiVA: diva2:385679
authorCount :32011-01-122011-01-102011-10-10Bibliographically approved