Development of an ultra‐performance liquid chromatography‐electrospray ionization‐Orbitrap mass spectrometry method for determination of xanthopurpurin in rat plasma and its application to pharmacokinetic study

A rapid and sensitive method was developed and validated for the quantitative determination of xanthopurpurin (XPP) in rat plasma using ultra‐performance liquid chromatography‐electrospray ionization‐Orbitrap mass spectrometry. XPP inhibits IgE production and prevents peanut‐induced anaphylaxis. The XPP and emodin (internal standard) were determined in negative ion mode with m/z 239.0350 → 211.0400 and 269.0455 → 241.0507, respectively. The separation process was achieved using an ACQUITY UPLC HSS T 3 column with acetonitrile and 0.1% formic acid in water (85:15). The linear range was 0.5–100 ng/mL, and the correlation coefficient ( r 2 ) was > 0.993. The inter‐day and intra‐day precision was within an acceptable range of 15%. The extraction recovery and matrix effect were 78.9–87.2% and 94.3–98.5%, respectively. Under different conditions, the XPP was stable in the range of 5.6–10.6%. This method was successfully applied to study the pharmacokinetics of XPP with an oral dose of 10.0 mg/kg and intravenous dose of 2.0 mg/kg in rats. The absolute oral bioavailability of XPP was 4.6%.