Simultaneous determination and tissue distribution studies of four phenolic acids in rat tissue by UFLC-MS/MS after intravenous administration of salvianolic acid for injection.

A rapid, simple and sensitive ultra-fast liquid chromatography tandem mass spectrometric method was developed and validated for simultaneous determination and tissue distribution studies of rosmarinic acid, salvianolic acid D, lithospermic acid and salvianolic acid B in rats after intravenous administration of salvianolic acid for injection. The tissue homogenate samples were pretreated by protein precipitation with pre-cooled acetonitrile. Chromatographic separation was achieved on a Waters Cortecs UPLC C18 column (1.6 μm, 2.1 × 100 mm) with a mobile phase composed of 0.1% formic acid-water and 0.1% formic acid-acetonitrile. Analytes were detected by electrospray ionization mass spectrometry and quantitated using multiple reaction monitoring. The method was fully validated. The calibration curves for the four phenolic acids were linear in the given concentration ranges. The precisions (relative standard deviation) in the measurement of quality control samples were <10% and the accuracies (relative error) were in the range of 0.28-11.22%. The reliable method was successfully applied to the tissue distribution studies of the four phenolic acids. The results showed that rosmarinic acid, salvianolic acid D, lithospermic acid and salvianolic acid B were rapidly distributed in tissues with the major amount found in kidney, and little crossed the blood-brain barrier. The developed method and the results provide a basis for further studies.