School of Medicine, Division of Pharmacy, Faculty of Health, University of Tasmania, Hobart, Tasmania, Australia.
School of Health Sciences, Faculty of Health, University of Tasmania, Launceston, Tasmania, Australia.
PLoS One. 2019 May 6;14(5):e0216039. doi: 10.1371/journal.pone.0216039. eCollection 2019.
Glucosamine dietary supplements are commonly used for the management of osteoarthritis (OA). However, clinical trials have reported varying outcomes with regard to joint function and disease progression. One of the possible reasons for variability in observed effects of glucosamine could be that, unlike prescription drugs, the quality of manufactured dietary supplements is not closely monitored in many countries. Therefore, there is the possibility that the actual amount of glucosamine present in a dietary supplement is different from that claimed on the label. The quality control of glucosamine supplements is further complicated by the unavailability of a simple and effective analytical method for the analysis of glucosamine. Therefore, the aim of this study was to develop a simple analytical method that could be easily adapted by the pharmaceutical industry for routine analysis of glucosamine.
To develop a novel high-performance liquid chromatography (HPLC) method for the quantification of glucosamine, and determine the amount of glucosamine present in a sample of dietary supplements commercially available in Australia and India.
Chromatographic separation of glucosamine was achieved using a zwitter-ionic hydrophilic interaction liquid chromatography column with a mobile phase consisting of 60% acetonitrile and 40% of 85 mM ammonium acetate, at a flow rate of 0.3 mL/min and column temperature 40°C. The developed method was validated for intra- and inter-day linearity, accuracy, precision, and reproducibility. The newly-developed method was subsequently used to analyse 12 glucosamine supplements.
The developed method was selective for glucosamine, which had a retention time of 5.9 min. The standard curve was linear with a correlation coefficient (r2) exceeding 0.99, over the range of 10-200 μg/mL for glucosamine. The relative standard deviations for intra- and inter-day accuracy, precision and reproducibility were all less than 4%. The amount of glucosamine determined in six Australian and six Indian glucosamine supplements ranged between 98.7-101.7% and 85.9-101.8% of the labelled values, respectively.
Unlike previous HPLC methods, this newly-developed HPLC technique does not require pre-derivatisation and can separate glucosamine from both hydrochloride and sulphate salts, and from other amino sugars, such as chondroitin sulphate present in dietary supplements. This simple and effective technique can be employed by analytical laboratories for the quality control of glucosamine dietary supplements.
The current study has developed a new analytical technique using HPLC-Corona CAD, which can analyse underivatised glucosamine hydrochloride and sulphate within 6 minutes. Using the novel assay, we confirmed that unlike the tested Australian dietary supplements, only half of the tested Indian products had a glucosamine content within ±10% of what was claimed on the label.
氨基葡萄糖膳食补充剂常用于骨关节炎（OA）的治疗。然而，临床试验报告称，其在关节功能和疾病进展方面的结果存在差异。氨基葡萄糖观察到的作用存在差异的一个可能原因是，与处方药不同，许多国家并没有密切监测制造膳食补充剂的质量。因此，膳食补充剂中实际存在的氨基葡萄糖数量可能与标签上声称的数量不同。由于缺乏一种简单有效的分析方法来分析氨基葡萄糖，因此氨基葡萄糖补充剂的质量控制变得更加复杂。因此，本研究的目的是开发一种简单的分析方法，使制药行业能够轻松适应常规分析氨基葡萄糖。
开发一种新型高效液相色谱（HPLC）方法，用于定量分析氨基葡萄糖，并确定在澳大利亚和印度市售膳食补充剂样品中的氨基葡萄糖含量。
采用两性离子亲水相互作用液相色谱柱，以 60%乙腈和 40%85mM 乙酸铵为流动相，流速为 0.3mL/min，柱温 40°C，实现氨基葡萄糖的色谱分离。所开发的方法针对日内和日间线性、准确性、精密度和重现性进行了验证。随后，新开发的方法用于分析 12 种氨基葡萄糖补充剂。
所开发的方法对氨基葡萄糖具有选择性，其保留时间为 5.9 分钟。氨基葡萄糖的标准曲线呈线性，相关系数（r2）超过 0.99，范围为 10-200μg/mL。日内和日间准确性、精密度和重现性的相对标准偏差均小于 4%。在六种澳大利亚和六种印度氨基葡萄糖补充剂中，氨基葡萄糖的含量分别为标签值的 98.7-101.7%和 85.9-101.8%。
与以前的 HPLC 方法不同，这种新开发的 HPLC 技术不需要衍生化，可以将氨基葡萄糖与盐酸盐和硫酸盐以及膳食补充剂中存在的其他氨基糖（如硫酸软骨素）分离。这种简单有效的技术可用于分析实验室对氨基葡萄糖膳食补充剂的质量控制。
本研究使用高效液相色谱-电喷雾检测（HPLC-ESI）开发了一种新的分析技术，可在 6 分钟内分析未衍生的盐酸盐和硫酸盐形式的氨基葡萄糖。使用新的测定方法，我们证实与测试的澳大利亚膳食补充剂不同，只有一半的测试印度产品的氨基葡萄糖含量在标签声称值的±10%范围内。
