HIGH PERFORMANCE LIQUID CHROMATOGRAPHIC DETERMINATION OF THE MAIN ALKALOIDS IN WU TOU (ACONITE)

The crude drug, aconite, prepared from the root of certain species of Aconitum is an important Chinese traditional medicine. The raw root of Aconitum plant contains some very toxic alkaloids such as aconitine, mesaconitine and hypaconitine etc. They are usually processed to lower the alkaloid content before used as a drug.In order to evaluate the quality of the drugs, a rapid, specific and precise method using HPLC was developed for the separation and quantitation of the alkaloids in aconite or its processed form.The procedure, is as follows:After alkalinizing the powdered sample with ammonia, macerate it with ether for 2 hours. Filter and wash the residue three times with small amount of fresh ether. Evaporate the combined ether extract to dryness. Add a certain amount of β-methynaphthalene as internal standard. Make the volume to 1 ml with methanol. Inject the methanolic solution onto a column of octadecylsilane chemically bonded phase and develop the chromatogram with MeOH-H₂O-CHCl₃-triethylamine (70:30:2:0.1). Aconitine, mesaconitine and hypaconitine are base line separated. Quantify the alkaloids by peak height ratio.Samples from varioussources were analyzed. The alkaloid content and their proportion differ widely.