Determination of ephedra alkaloids by liquid chromatography/tandem mass spectrometry.
In conjunction with an AOAC Task Group on dietary supplements, a liquid chromatography/tandem mass spectrometry (LC-MS/MS) method was validated for measurement of 6 major alkaloids in raw ephedra sinica herb, ephedra extracts, ephedra tablets, complex dietary supplements containing ephedra, and a high-protein drink mix containing ephedra. The amount of ephedrine-type alkaloids present was determined by LC with mass selective detection. Six replicates of each matrix were analyzed on 3 separate occasions. The presence of 6 ephedrine-type alkaloids was detected at a level > 0.5 microg/g based on a 0.5 g sample. The standard curve range for this assay is from 0.02 to 1.0 microg/mL. Appropriate dilutions covered a wide range of specific alkaloid concentrations. The calibration curves for all 6 analytes had correlation coefficients > 0.995.
Sullivan
Darryl
D
Covance Laboratories, 3301 Kinsman Blvd, Madison, WI 53704, USA. darryl.sullivan@covance.com
Wehrmann
James
J
Schmitz
John
J
Crowley
Richard
R
Eberhard
Jeffrey
J
D000470:Alkaloids / Q000032:analysis*; D002138:Calibration; D002853:Chromatography, Liquid; D029789:Ephedra / Q000737:chemistry*; D013058:Mass Spectrometry
D000470:Alkaloids