Determination of the Hemoglobin Adduct 2-Hydroxyethylvaline by HPLC with Electrospray Ionization and High Resolution Time-of-Flight Mass Spectrometry Quantitation

摘要

This work demonstrates the utility of using accurate masses obtained from a time-of-flight mass spectrometer for low-level quantitation of biomarkers of exposure such as hemoglobin adducts, over a wide concentration range. Taking advantage of the specificity provided by an accurate mass instrument, enhanced signal/noise response was obtained. Extracting a very narrow mass range for the analyte and the D_(4)-HEVal internal standard, considerably improved specificity. Incorporating an isotopically labeled internal standard into this analysis method was invaluable. Since the sample workup is involved and there is inherent drift in ESI/MS response, addition of the internal standard to the globin matrix greatly enhanced the accuracy and precision of the acquired data. In addition, this instrument employs an ADC signal processor which has an enhanced dynamic range (compared to older TDC technology) which allows internal standard calibration to be used (4).