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PUBLICATIONS

Determination of Bitter Orange Alkaloids in Dietary Supplements Standard Reference Materials by Liquid Chromatography With Ultraviolet Absorbance and Fluorescence Detection

Published

Author(s)

Karsten Putzbach, Katherine E. Sharpless, Lane C. Sander

Abstract

Four adrenergic amines [(+/-) synephrine, (+/-) octopamine, tyramine, and n-methyltyramine) were determined in a variety of Citrus aurantium (Bitter Orange) containing dietary supplements. Two extraction techniques were evaluated in detail: Soxhlet extraction and sonication extraction. A liquid chromatographic separation using a reversed-phase C18 stationary phase and the ion-pairing reagent sodium dodecyl sulfate was developed to separate the bitter orange alkaloids. Ultraviolet absorbance detection at 220 nm and fluorescence detection with excitation at 273 nm and emission at 304 nm were used for the alkaloid detection. The method described was used for the assignment of the levels of the predominant alkaloids in three candidate Standard Reference Materials containing Citrus aurantium.
Citation
Journal of Chromatography
Volume
1156
Pub Type
Journals

Keywords

bitter orange alkaloids, citrus aurantium, fluorescence detection, Standard Reference Materials, synephrine

Citation

Putzbach, K. , Sharpless, K. and Sander, L. (2007), Determination of Bitter Orange Alkaloids in Dietary Supplements Standard Reference Materials by Liquid Chromatography With Ultraviolet Absorbance and Fluorescence Detection, Journal of Chromatography (Accessed October 14, 2025)

Issues

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Created April 24, 2007, Updated February 17, 2017
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