Liquid chromatographic-tandem mass spectrometric method for the determination of the neuraminidase inhibitor zanamivir (GG167) in human serum

An LC-MS-MS method for the analysis of the neuraminidase inhibitor, zanamiv ir, in human serum is described. Zanamivir was extracted from protein preci pitated human serum samples using Isolute SCX solid-phase extraction cartri dges and analysed using reversed-phase chromatography with TurboIonSpray at mospheric pressure ionisation followed by mass spectrometric detection. The method uses a stable isotope internal standard, is highly specific and sen sitive for a compound of this type and has been used for the analysis of hu man serum and urine samples from clinical studies. The method was extended to the analysis of serum and plasma samples from pre-clinical studies invol ving the rat, ferret and cell culture media. The method has been shown to b e robust and valid over a concentration range of 10-5000 ng/ml using a 0.2- mI sample volume. The main advantages of this method compared to earlier pr ocedures are primarily specificity, sensitivity, ease of sample preparation , small sample volume and short analysis time (ca. 5 min). (C) 1999 Elsevie r Science B.V. All rights reserved.