Determination of geniposidic acid in rat plasma by LC–MS/MS and its application to in vivo pharmacokinetic studies

A simple, rapid and sensitive method for the determination of geniposidic acid (GSA) in rat plasma was developed using liquid chromatography tandem mass spectrometry (LC–MS/MS). Geniposide (GS) was used as the internal standard. Rat plasma pretreated by solid-phase extraction (SPE) was analyzed by LC–MS/MS with negative ion mode electrospray ionization (ESI) in the multiple reaction monitoring (MRM) mode. The analytical column was C8 column and the mobile phase was methanol (A) and water (B). The flow rate was set at 0.8 mL/min with split ratio of 1:3, the total run time was 15 min. The MS/MS ion transitions monitored were m/z 373.3–211.1 for GSA and m/z 387.3–225.3 for GS. The quantification limit was 5 ng/mL within a linear range of 10–4000 ng/mL. The inter-day and intra-day accuracy and precision were within ±10%. The method was fully validated for its sensitivity, selectivity, matrix effect, stability study and recovery. The data indicate that our LC–MS/MS assay is an effective method for the pharmacokinetics study of GSA in rat plasma.