Application of liquid chromatography atmospheric pressure chemical ionization tandem mass spectrometry in the quantitative analysis of glyburide (glibenclamide) in human plasma

Glyburide (glibenclamide) is widely prescribed in the treatment of Type II diabetes. A validated liquid chromatography atmospheric pressure chemical i onization tandem mass spectrometry (LC/APCI-MS/MS) method for the determina tion of glyburide is reported. The method uses a stable isotope labeled gly buride as the internal standard. Subsequent to acetonitrile protein precipi tation, the supernatant was directly (unfiltered) injected onto the LC colu mn (retention time similar to 3 min) for analysis. A lower limit of quantif ication (LLOQ) of 1.01 ng/mL was attained for the human plasma assay. The m ethod was fast, specific, and exhibited excellent ruggedness. It was succes sfully applied to the analysis of clinical samples from patients dosed with glyburide, Copyright (C) 1999 John Wiley & Sons, Ltd.