By Joseph Zhou, Ph.D., NOW Quality Control
AOAC INTERNATIONAL is a 120 year-old not-for-profit scientific association committed to worldwide confidence in analytical results. As the AOAC Study Director on determining the official method for testing glucosamine products, I organized twelve validation laboratories world-wide and performed a collaborative study for determination (testing) of glucosamine sulfate and glucosamine hydrochloride in both raw materials and dietary supplement finished products. Before the study began, a protocol for the study was prepared and approved by the AOAC Expert Review Panel (ERP) on the method. AOAC has high standards for the collaborative study to ensure the method, once approved, is technically sound and valid.
Among the twelve collaborating laboratories for the study, three were industrial manufacturers of finished products, five were raw material vendors, three were commercial testing laboratories, and one was an university laboratory. Geographically, ten laboratories were from the United States, one from Canada, and one from Germany. Five types of test materials were used in the study: (1) tablets, (2) capsules, (3) drink mix powders, (4) raw materials, and (5) liquid products. The materials selected included glucosamine from shellfish as well as vegetable sources, both the hydrochloride and sulfate salts, and glucosamine in combination with other ingredients commonly found to co-occur in dietary supplements, including MSM, SAMe, chondroitin sulfates and vitamin C, at levels commonly found in commercial products.
The study was conducted successfully. The method was proved to be simple, precise and accurate. All of the twelve collaborating laboratories succeeded in the study and none of their reported test results were outliers (outside the typical range of test results), indicating the robustness of the method. After carefully reviewing the data and report from the collaborative study, the AOAC Methods Committee on Dietary Supplements voted unanimously to approve this method as an AOAC First Action Official Method MS. AOAC Official Methods of Analysis have been defined as official by regulations promulgated for enforcement of the Food, Drug, and Cosmetic Act (21 CFR 2.19), recognized in Title 9 of USDA-FSIS Code of Federal Regulations, and in some cases by the US Environmental Protection Agency.
The method was designated as AOAC method 2005.01 with the title, Determination of Glucosamine in Raw Materials and Dietary Supplements Containing Glucosamine Sulfate and/or Glucosamine Hydrochloride by HPLC with FMOC-Su Derivatization. The collaborative study report and the standard operation procedures (SOP) of this official method was published in Journal of AOAC, International (References 1, 2).
Glucosamine products make up one of the most popular dietary supplement categories, and its effectiveness has been clinically validated for use with osteoarthritis. The established AOAC glucosamine official method was developed at NOW Foods. NOWs scientists have developed many excellent analytical methods to support our product development and quality control. NOWs accomplishment in this glucosamine method demonstrates NOWs commitment to quality testing and outstanding product quality, as well as our commitment to be a leader in product quality. NOWs glucosamine products are of the highest standards because we test using the new official method, which we ourselves developed.
1 The AOAC INTERNATIONAL publication, Inside Laboratory Management, July/August 2005, Page 5.
2 J. Zhou, T. Waszkuc, F. Mohammed, C. Ray, R. Buren, W. Wang, H.Nguyen, J. Jabusch, D. Sullivan, X. Kou, Q. Yang, A. Solyom, J. Wang, T. Peng, Q. Zheng, M. Blumhorst, M. Nagarajan, B. Podhola, L. Huang, C. Shevchuk, R. Das, K. Orellana, K. Reif. Determination of Glucosamine in Raw Materials and Dietary Supplements Containing Glucosamine Sulfate and/or Glucosamine Hydrochloride by High Performance Liquid Chromatography with FMOC-Su Derivatization: Collaborative Study. Will be published in Journal of AOAC INTERNATIONAL, July/August, 2005.