Simultaneous chiral separation of ephedrine alkaloids by MEKC-ESI-MS using polymeric surfactant II: application in dietary supplements.
Chiral MEKC-MS method was utilized for separation, identification, and quantitation of ten enantiomers of ephedrine and related compounds. Enantioselective separations of all ephedrine alkaloids were accomplished through a combination of polysodium N-undecenoxycarbonyl-L-leucinate (poly-L-SUCL) with 30% v/v ACN. Interestingly, the more hydrophilic stereoisomers were eluted later than the hydrophobic ones indicating that hydrogen bonding interactions are much stronger than hydrophobic interactions in the presence of ACN in chiral MEKC. The method was validated in terms of linearity, LOD, LOQ, precision and robustness. The method was finally used in the analysis of three standard reference materials (SRMs). Results of (-)-ephedrine ranged from 12.49 to 0.24 mg/g, for (+)-pseudoephedrine from 4.04 to 0.019 mg/g, for (-)-norephedrine from 0.36 to 0.0031 mg/g, for (+)-norpseudoephedrine from 0.68 to 0.0052 mg/g, for (-)-methylephedrine from 1.18 to 0.0092 mg/g and for (+)-methylpseudoephedrine from 0.086 to 0.00037 mg/g in the SRMs.
Hou
Jingguo
J
Department of Chemistry, Center of Biotechnology and Drug Design, Georgia State University, Atlanta, GA 30303, USA.
Zheng
Jie
J
Shamsi
Shahab A
SA
D000470:Alkaloids / Q000302:isolation & purification*; D020374:Chromatography, Micellar Electrokinetic Capillary / Q000379:methods*; D019587:Dietary Supplements / Q000032:analysis*; D029790:Ephedra sinica / Q000737:chemistry; D004809:Ephedrine / Q000032:analysis*; D057927:Hydrophobic and Hydrophilic Interactions; D008823:Micelles; D011108:Polymers / Q000737:chemistry; D012015:Reference Standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D013237:Stereoisomerism; D013501:Surface-Active Agents / Q000737:chemistry*
D000470:Alkaloids; D008823:Micelles; D011108:Polymers; D013501:Surface-Active Agents; D004809:Ephedrine