UFLC-MS/MS method for simultaneous determination of luteolin-7-O-gentiobioside, luteolin-7-O-β-D-glucoside and luteolin-7-O-β-D-glucuronide in beagle dog plasma and its application to a pharmacokinetic study after administration of traditional Chinese medicinal preparation: Kudiezi injection.

A rapid, sensitive and selective ultra-fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) method for the simultaneous determination of three active flavonoid glycosides: luteolin-7-O-gentiobioside, luteolin-7-O-β-D-glucoside and luteolin-7-O-β-D-glucuronide in beagle dog plasma was developed and validated. Puerarin was used as internal standard (IS). After protein precipitation with acidified acetonitrile, the analytes were separated on a Venusil MP C18 column with a gradient elution system composed of 0.05% formic acid and acetonitrile at a flow rate of 0.4ml/min. Detection was performed using multiple reaction monitoring (MRM) mode with a turbo ion spray source under a negative ionization condition. The calibration curves of the three analytes showed good linearity (r>0.995) within the tested concentration ranges. The lower limits of quantification for luteolin-7-O-gentiobioside, luteolin-7-O-β-D-glucoside and luteolin-7-O-β-D-glucuronide were 1.0 ng/ml, 1.0 ng/ml and 4.0 ng/ml, respectively. The intra-day and inter-day precision and accuracy deviations were less than 15%, and the extraction recoveries of the three analytes from beagle dog plasma were more than 75%. The validated method was successfully applied to a pharmacokinetic study of the three flavonoid glycosides in beagle dog plasma after intravenous administration of the traditional Chinese medicinal preparation: Kudiezi injection.