A Rapid and Sensitive UPLC?￠????ESI-MS/MS Method for Determination ofLevonorgestrel by Chemical Derivatization in Human Plasma and itsApplication to Pharmacokinetic Study

摘要

A rapid and sensitive liquid chromatography–tandem mass spectrometry (LC–MS/MS) method in human plasma was developed for determination of levonorgestrel using ultra performance liquid chromatography aligned with tandem mass spectrometric detection. The analytes were extracted using solid–phase extraction technique followed by rapid derivatization. Levonorgestrel and levonorgestrel d6 were resolved on Kromasil C18 (50 × 4.6 mm) using gradient flow acetonitrile and 0.1% formic acid solution with a total run time of 5 minutes. The detection was achieved using Waters XEVO–TQ–S mass spectrometry system with a mass transition ion-pair of m/z 328.2 → 90.9 for levonorgestrel and m/z 334.1 → 91.0 for levonorgestrel D6. The method has been validated for a linear range of 100–30000 pg/ml with a correlation coefficient ≥ 0.99. The precision (%RSD) was less than 6.50% and accuracy (%RE) was within ± 5%. The overall recoveries for levonorgestrel and levonorgestrel D6 were 93.69% and 93.88% respectively. The validated method was applied for the pharmacokinetic study of levonorgestrel following a single oral dose of levonorgestrel/ethinyl estradiol (0.15 mg/0.03 mg) tablets in 36 healthy female volunteers.