A sensitive, high-throughput, and eco-friendly analysis of daidzein and its valine carbamate prodrug in rat plasma by supercritical fluid chromatography with tandem mass spectrometry.

A valine carbamate prodrug of daidzein was synthesized to improve its bioavailability because of the poor solubility and low permeability of daidzein. To evaluate the pharmacokinetic behavior of the prodrug, a sensitive and high-throughput method was developed and validated for the simultaneous determination of daidzein and its prodrug in rat plasma. The samples were extracted by ethyl acetate and then analyzed by a supercritical fluid chromatography with electrospray ionization tandem mass spectrometry method. The separation was achieved by an ACQUITY UPC ™ BEH 2-EP column maintained at 40°C using carbon dioxide (≥99.99%) and methanol within 3.0 min by gradient elution. The mass transition ion pairs were m/z 254.8→136.7, 398.0→254.9, and 271.0→91.07 for daidzein, the prodrug, and genistein, respectively. The calibration curves were linear over the concentration ranges of 2-500 (r > 0.997) and 10.0-5000.0 ng/mL (r > 0.996) with lower limits of quantification of 2 and 10 ng/mL for daidzein and the prodrug, respectively. The intra- and interday accuracy and precision were within ±15% for all quality control samples. This developed method enabled high specificity, low cost, low solvent consumption, and a brief analysis time and was successfully applied to a bioavailability evaluation of daidzein and its carbamate prodrug.