Abstract
A liquid chromatography/tandem mass spectrometric (LC/MS/MS) assay was developed for the quantitative determination of 2-methoxyestradiol (2ME2) in human plasma. Sample pretreatment involved liquid-liquid extraction with ethyl acetate of 0.3-mL aliquots of plasma spiked with the internal standard, deuterated 2ME2 (2ME2-d5). Separation was achieved on a Zorbax Eclipse® C18 column (2.1 x 50 mm, i.d., 5 μm) at room temperature using a gradient elution with methanol and water at a flow rate of 0.25 mL/min. Detection was performed using atmospheric pressure chemical ionization MS/MS by monitoring the ion transitions from m/z 303.1 → 136.8 (2ME2) and m/z 308.1 → 138.8 (2ME2-d5). Calibration curves were linear in the concentration range of 1-100 ng/ mL. The accuracy and precision values, obtained from three different sets of quality control samples analyzed in quintuplicate on four separate occasions, ranged from 105-108% and from 3.62-5.68%, respectively. This assay was subsequently used for the determination of 2ME2 concentration in plasma of a patient with cancer after a single oral administration of 2ME2 at a dose of 2200 mg.
| Original language | English |
|---|---|
| Pages (from-to) | 1176-1182 |
| Number of pages | 7 |
| Journal | Rapid Communications in Mass Spectrometry |
| Volume | 19 |
| Issue number | 9 |
| DOIs | |
| State | Published - 2005 |
| Externally published | Yes |