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Updated: Aug 30, 2026

An Efficient and Rapid HPLC-QQQ-MS Method for the Quantitation of Tropane Alkaloids in Medicinal Plants
Published on: June 12, 2026
Quantitative analysis of ephedrine analogues from ephedra species using 1H-NMR
Hye Kyong Kim1, Young Hae Choi, Wen-Te Chang
1Division of Pharmacognosy, Institute of Biology, Leiden University, The Netherlands.
Abstract:
Four ephedrine analogues such as ephedrine, pseudoephedrine, methylephedrine, and methylpseudoephedrine were determined by (1)H-NMR from Ephedra species. In the region of delta 5.0-4.0, the signals of H-1 attached to the same carbon with a hydroxyl, were well separated from each other in CDCl(3). The amount of each alkaloid was calculated by the relative ratio of the intensity of H-1 signal to the known amount of internal standard, 200 microg of anthracene. This method allows rapid determination of the quantity of four ephedrine alkaloids from Ephedra species. The amount of these alkaloids was in the range of 1.0-2.0% of dry weight depending on the plant materials.
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