Rapid, simple, specific liquid chromatographic-electrospray mass spectrometry method for the determination of glibenclamide in human plasma

A sensitive liquid chromatographic-electrospray ionization mass spectrometric method was developed and validated for fast determination of glibenclamide in human plasma. After deprotienation with methanol, centrifugation, evaporation to dryness and dissolving in mobile phase, samples were separated using a Hypersil-Keystone C18 reversed-phase column (150 mm×2.1 mm ID, 5 (mu)m), together with a mobile phase containing of acetonitrile–10 mM ammonium acetate (55:45, v/v), 0.2% acetic acid and 0.1% trifluoracetic acid. Glibenclamide and its internal standard, glipizide, were measured by electrospray ion source in positive selective ion monitoring mode. The method demonstrated linearity from 1 to 400 ng/mL (r=0.998). The limit of quantification for glibenclamide in plasma was 1 ng/mL with good accuracy and precision. The recovery of the method was over 91.5%. Intra- and inter-day precision ranged from 3.42 to 5.57 and 7.49 to 8.64% (RSD), respectively.