RESUMO
Objective To supply evidence for quality control of Herba Ephedra by determining content limit in different batches of medicinal material of Herba Ephedra.Methods A RP-HPLC method was used for the determination of ephedrine and pseudo-ephedrine. The chromatographic conditions were: Kromasil RP-C18(250?4.6 mm,5 ?m) column, a mixture of 0.3 %phosphoric acid-methanol (10∶90) as mobile phase and 213nm as detected wavelengths.Results The contents of the above two alkaloids showed great difference among the 14 patches of tested samples. The content of ephedrine ranged 0.361 %～1.538 %and that of pseudo-ephedrine 0.332～2.087 %. The suggested content limitation of ephedrine should be 1.082 %, and that of psedoephedrine be 1.008 %in the crude Herba Ephedra.Conclusion The established method has been proven to be simple, stable and repeatable, and can be applied for quality control of the crude crude Herba Ephedra and compound prescriptions containing crude Herba Ephedra.