title: A rapid and simple procedure for the determination of synephrine in dietary supplements by gas chromatography-mass spectrometry.
abstract: A simple and rapid procedure based on gas chromatography-mass spectrometry (GC-MS) is described for determination of synephrine, active principle of Citrus aurantium plant, in solid and liquid dietary supplements. After the addition of 3,4-methylenedioxypropylamphetamine as internal standard (I.S.), a liquid-liquid extraction procedure in alkaline conditions with chloroform/isopropanol (9:1, v/v) was applied to the samples prior to analysis. Chromatography was performed on a fused capillary column and synephrine and I.S., derivatized with pentafluoropropionic anhydride, were determined in the selected-ion-monitoring (SIM) mode. The method was validated in the range 0.1-50 microg/mg or microg/mL synephrine. Mean recovery ranged between 89.3% and 90.5% in both solid and liquid dietary supplements. The quantification limit was 0.1 microg/mg or microg/ml. The method was applied to analysis of various dietary supplements promoted for aiding weight control containing, among other constituents such as ephedrine alkaloids and methylxanthines, Citrus aurantium. Amount of synephrine present in such products ranged from 3.1 microg/mg solid product to 480.2 microg/mL liquid product.
authors.affiliation: Drug Control and Evaluation Department, Istituto Superiore di Sanitá, V.le Regina Elena 299, 00161, Rome, Italy.
authors.forename: Emilia
authors.initials: E
authors.lastname: Marchei
authors.forename: Simona
authors.initials: S
authors.lastname: Pichini
authors.forename: Roberta
authors.initials: R
authors.lastname: Pacifici
authors.forename: Manuela
authors.initials: M
authors.lastname: Pellegrini
authors.forename: Piergiorgio
authors.initials: P
authors.lastname: Zuccaro
mesh_terms: D002957:Citrus; D005526:Food, Formulated / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D015203:Reproducibility of Results; D013578:Synephrine / Q000032:analysis*; D014662:Vasoconstrictor Agents / Q000032:analysis*
chemical_list: D014662:Vasoconstrictor Agents; D013578:Synephrine