Determination and pharmacokinetics of geniposidic acid in rat plasma after oral administration of Gardeniajasminoides fruit crude extract and Zhi‐zi‐chi decoction

A simple and efficient liquid chromatography-mass spectrometry method was developed and validated for the determination of geniposidic acid in rat plasma. After the addition of internal standard salidroside and acidification (0.1% formic acid, pH = 3.2), plasma samples were carried out by protein precipitation with acetonitrile and separated on a Kromasil C18 column (150 × 4.6 mm, 5 µm) within a run time of 9.0 min. Analysis was performed in selected ion monitoring mode with a positive electrospray ionization interface. No endogenous interference was observed at retention times of the analytes because of the high specificity of selected ion monitoring mode. The linear range was 0.02-4.0 µg/mL and the lower limit of quantification was 0.02 µg/mL. The mean extraction recoveries of geniposidic acid and internal standard from rat plasma were all >88.0% and the matrix effects were within acceptance criteria (90-110%). The validated method was successfully applied to the pharmacokinetic study of geniposidic acid in rat plasma after oral administration of G. jasminoides fruit crude extract and Zhi-zi-chi decoction, respectively.