LC-ESI-MS/MS analysis and pharmacokinetics of jolkinolide B, a potential antitumor active component isolated from Euphorbia fischeriana, in rat plasma.

A simple, specific and reproducible liquid chromatography-electrospray ionization mass spectrometry was developed and validated for the determination of jolkinolide B, a potential antitumor active component isolated from Euphorbia fischeriana, in rat plasma. Chromatographic separation was achieved on a Venusil MP-C18 column using an isocratic elution. Jolkinolide B and osthole (internal standard) were monitored by positive electrospray ionization in the selected reaction monitoring mode. Good linearity (r(2) > 0.996) was achieved by a weighted (1/x(2) ) linear least-squares regression over a concentration range of 6.50-2600 ng/mL. The accuracy and precision of the assay were satisfactory and the method proved to be applicable to pharmacokinetics following a single intravenous bolus injection of jolkinolide B to rats.