Serum pharmacochemistry and pharmacokinetics of major components after oral administration of Luhong recipe in rats using ultra‐performance liquid chromatography–tandem mass spectrometry

Luhong recipe (LHR) is has been used as an empirical prescription for treating chronic heart failure for long, with safety, reliability, and significant efficacy. However, its pharmacokinetics has not yet been studied. This study aims to establish a ultra performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) method for the simultaneous analysis of epimedin A, epimedin B, epimedin C, icariin, psoralen, and isopsoralen in rat plasma and apply it to the pharmacokinetic study of LHR after oral administration. These six analytes were ionized using positive electrospray ionization (ESI+ ). The MS/MS transitions used for monitoring are successively converted to m/z 839.3 → 369.1, m/z 809.2 → 369.1, m/z 823.3 → 369.1, m/z 677.2 → 205.2, m/z 187.1 → 115.2, and m/z 230 → 120.9. Linearity, precision, accuracy, stability, matrix effect, and recovery of the established method were within the acceptable range. The method was suitable for the determination of six analytes after oral administration of LHR. The pharmacokinetic results showed that the time to reach the peak concentration (Tmax ) was from 0.17 to 13.5 h, the peak concentration (Cmax ) was 109.23-980 ng/mL, the area under the concentration-time curve (AUC[0 - t] ) was 65.48-8846.08 ng·h/mL, and the apparent distribution volume (Vd) was 24,772-896,132 mL/kg. These results provided a meaningful basis for formulating the clinical dose regimen of LHR.