Harcher Artturi, Ricard Connor, Connolly Danielle, Gibbs Isabel, Shaw Jarve, Butler Jillian, Perschbacher Julia, Replogle Lindsay, Eide Michaela, Grissom Morgan, O'Neal Oliver, Nguyen Quan, Nguyen Van Hac, Hunnicutt Michael, Mahmoud Roaa, Dhakal Soma
Department of Chemistry, Virginia Commonwealth University, 1001 West Main Street, Richmond, VA 23284, USA.
Methods Protoc. 2025 Jan 6;8(1):5. doi: 10.3390/mps8010005.
Quinine is known for treating malaria, muscle cramps, and, more recently, has been used as an additive in tonic water due to its bitter taste. However, it was shown that excessive consumption of quinine can have severe side effects on health. In this work, we utilized fluorescence spectroscopy to measure the concentration of quinine in commercial tonic water samples. An external standard method was used to calculate the concentrations of quinine in two commercially available tonic water brands, namely Canada Dry and Schweppes, and compare them to the maximum allowable concentration of quinine in beverages. Upon analysis of the data collected by five different groups, the levels of quinine were found to be above the average concentration in most commercial tonic water samples, but below the maximum permitted concentration. Moreover, the five replicate sets of data demonstrated high reproducibility of the method employed in this study. The simple yet instructive protocol that we developed can be adapted to determine the concentration of other fluorescent compounds in foods and beverages. Further, the presented method and detailed protocol can be easily adopted for undergraduate labs and in chemical education.
奎宁以治疗疟疾、缓解肌肉痉挛而闻名，最近，由于其苦味，它还被用作奎宁水中的添加剂。然而，研究表明，过量摄入奎宁会对健康产生严重的副作用。在这项工作中，我们利用荧光光谱法测量了市售奎宁水中奎宁的浓度。采用外标法计算了两个市售奎宁水品牌（加拿大干姜水和施韦ppes）中奎宁的浓度，并将其与饮料中奎宁的最大允许浓度进行了比较。通过对五个不同小组收集的数据进行分析，发现大多数市售奎宁水样品中奎宁的含量高于平均浓度，但低于最大允许浓度。此外，五组重复数据表明本研究中所采用方法具有很高的重现性。我们开发的这个简单而有启发性的方案可用于测定食品和饮料中其他荧光化合物的浓度。此外，所提出的方法和详细方案可很容易地应用于本科实验室和化学教学中。
