Validation of a high-performance liquid chromatography method for the determination of (-)-α-bisabolol from particulate systems

Abstract

A reversed-phase high performance liquid chromatography method has been developed and validated for determination and quantitation of the natural sesquiterpene (−)-α-bisabolol. Furthermore the application of the method was done by characterization of chitosan milispheres and liposomes entrapping Zanthoxylum tingoassuiba essential oil, which contains appreciable amount of (−)-α-bisabolol. A reversed-phase C18 column and gradient elution was used with the mobile phase composed of (A) acetonitrile–water–phosphoric acid (19:80:1) and (B) acetonitrile. The eluent was pumped at a flow rate of 0.8 mL/min with UV detection at 200 nm. In the range 0.02–0.64 mg/mL the assay showed good linearity (R2 = 0.9999) and specificity for successful identification and quantitation of (−)-α-bisabolol in the essential oil without interfering peaks. The method also showed good reproducibility, demonstrating inter-day and intra-day precision based on relative standard deviation values (up to 3.03%), accuracy (mean recovery of 100.69% ± 1.05%) and low values of detection and quantitation limits (0.0005 and 0.0016 mg/mL, respectively). The method was also robust for showing a recovery of 98.81% under a change of solvent in standard solutions. The suitability of the method was demonstrated by the successful determination of association efficiency of the (−)-α-bisabolol in chitosan milispheres and liposomes.