RP-HPLC determination of free gastrodin and total gastrodin in Gastrodia elata

Objective:To establish an HPLC method for determining the content of free gastrodin and total gastrodin of Gastrodia elata Bl.with gastrodin as control.Methods: The amounts of free gastrodin were determined by ChP method and by alkali-hydrolysis of total gastrodin of Gastrodia elata to determine the amounts of gastrodin,the amounts of total gastrodin and free gastrodin were determined by LUNA C18(2)(4.6 mm×150 mm,5 μm) column as analytical column,220 nm as detective wavelength,acetonitrile-0.05%phosphoric acid(3∶97) as mobile phase at a flow rate of 0.8 mL·min-1.Results:The standard curve of gastrodin was linear in the range of 0.097-0.484 μg(r=0.9997),and the average recovery(n=6) was 99.0%.Conclusion:This method is simple and can be easily repeated,and can be used for the quality control of Gastrodia elata.