Study on determination of cynarin in dietary supplement containing artichoke by high performance liquid chromatography
Abstract
There has been no announcement on the standardization and testing of cynarin in dietary supplements containing artichokes in Vietnam. The high-performance liquid chromatography (HPLC) method was developed to determine cynarin in dietary supplements containing artichokes. The sample was extracted twice with 80% methanol solvent and ultrasonicated at 50°C for 20 minutes. Centrifuge at 6000 rpm for 5 minutes, filter, and inject into HPLC system with XBridge C18 column (250 mm x 4,6 mm, 5 µm) and corresponding pre-column, mobile phase consisting of two solvents phosphoric acid 0,1% and acetonitrile eluted according to gradient program, flow rate 1mL/min, detection wavelength 322nm. The calibration curves for cynarin had R2 = 1, and the validation parameters met AOAC standards. The method detection limits and the limit of quantification were 3.00 mg/kg and 10.0 mg/kg, respectively. The validated method was applied to determine cynarin in 15 dietary supplement samples. The content of cynarin varied depending on the manufacturer.