Physicochemical characterization and pharmacokinetics evaluation of β-caryophyllene/β-cyclodextrin inclusion complex

β-Caryophyllene (BCP), a natural sesquiterpene existing in the essential oil of many plants, has exhibited a wide range of biological activities. However, its volatility and poor water-solubility limit its application in pharmaceutical field. β-Cyclodextrin (β-CD) has intrinsic ability to form specific inclusion complexes with different drugs to enhance their stability, solubility and bioavailability. The aim of this study is to investigate and compare the oral bioavailability and the pharmacokinetics of free BCP and BCP/β-CD inclusion complex after a single oral dose of 50 mg/kg on rats. A simple, rapid, and sensitive gas chromatography–mass spectrometry method in selected ion monitoring (GC–MS/SIM) mode was developed on determination of BCP in rat plasma. The in vivo data showed that BCP/β-CD inclusion complex displayed earlier Tmax, higher Cmax and the AUC0–12 h was approximately 2.6 times increase than those of free BCP. These results demonstrated that BCP/β-CD inclusion complex has significantly increased the oral bioavailability of the drug in rats than free BCP.