K. Yamaguchi et al., Development of a sensitive liquid chromatography-electrospray ionization mass spectrometry method for the measurement of KW-5139 in rat plasma, BIOMED CHRO, 14(2), 2000, pp. 77-81
A sensitive method for the determination of a prokinetic peptide, KW-5139 (
Leu(13)-motilin), in rat plasma has been developed utilizing liquid chromat
ography-electrospray ionization mass spectrometry (LC-ESI-MS). KW-5139 was
separated by reversed-phase HPLC, with a mixture of 75 mM ammonium formate
(pH 3.0) and acetonitrile (4:1, v/v), and monitored by single ion recording
(SIR)-ESI-MS at m/z 894 ([M+3H](3+)). Simple protein precipitation and thr
LC-ESI-MS analysis allowed the determination of KW-5139 in rat plasma with
the mean precision and accuracy at the lower limit of quantitation (LLOQ,
0.5 ng/mL) of 5.7 and 11.2%, respectively. The method was applied to the mo
nitoring of the plasma time-concentration profile of KW-5139, intravenously
administered to rats at a dose of 1 mu g/kg. Copyright (C) 2000 John Wiley
& Sons, Ltd.