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Certification of standard reference materials containing bitter orange.
L C Sander1, K Putzbach, B C Nelson
1National Institute of Standards and Technology, Chemical Science and Technology Laboratory, 100 Bureau Drive, MS 8392, Gaithersburg, MD 20899-8392, USA. lane.sander@nist.gov
Analytical and Bioanalytical Chemistry
|April 22, 2008
Summary
New standard reference materials for bitter orange dietary supplements ensure accurate alkaloid and caffeine measurements. These materials aid in validating analytical methods for supplement quality control.
Area of Science:
- Analytical Chemistry
- Pharmacognosy
- Dietary Supplements
Background:
- Dietary supplements containing bitter orange are popular for weight management.
- Accurate quantification of alkaloids and caffeine in these supplements is crucial for safety and efficacy.
- Lack of certified reference materials hinders reliable analytical testing.
Purpose of the Study:
- To develop and characterize standard reference materials (SRMs) for bitter orange dietary supplements.
- To establish reliable methods for quantifying key alkaloids and caffeine in these SRMs.
- To ensure the quality and consistency of bitter orange supplements through validated analytical techniques.
Main Methods:
- Development of three distinct dietary supplement SRMs incorporating bitter orange extract.
- Quantification of synephrine, octopamine, tyramine, N-methyltyramine, hordenine, total alkaloids, and caffeine.
- Utilized multiple, substantially independent analytical methods including varied extractions, separations, and detection techniques across three laboratories.
Main Results:
- Excellent agreement among measurements from multiple analytical methods.
- High data reproducibility, with most methods and analytes showing better than 5% relative standard deviation.
- Successful characterization of alkaloid and caffeine levels in the developed SRMs.
Conclusions:
- The developed bitter orange SRMs provide reliable measurement controls.
- These SRMs are valuable for the development and validation of analytical methods for dietary supplements.
- Enhanced accuracy in bitter orange supplement analysis supports consumer safety and regulatory compliance.
