Liquid chromatography–mass spectrometry determination in plasma of maslinic acid, a bioactive compound from Olea europaea L.

Maslinic acid, a pentacyclic triterpene from Olea europaea L., exerts hypoglycemic, antioxidant, cardioprotective and antitumoral activities. Here, an LC-APCI-MS method to determine this compound in plasma is presented as a first step in pharmacokinetic studies. Maslinic acid was extracted from plasma with ethyl acetate and separated on a C18 column using a gradient elution of water and acetonitrile. The target ions were m/z 471.3 for maslinic acid and m/z 455.3 for I.S. The method was validated by the analysis of spiked plasma samples obtaining a linear correlation, a recovery of 99.0 ± 0.9% and a quantification limit of 5 nM. The precision and accuracy were ⩽8.38% and ⩽4.82%, respectively. Finally, the method was verified by measuring the rat plasmatic concentrations 24 h after the single oral administration of 10, 25 and 50 mg/kg of maslinic acid, thereby ensuring that the procedure is appropriate for its use in bioavailability studies.