Kalisz Oktawia, Studzińska Sylwia, Bocian Szymon
Chair of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Nicolaus Copernicus University in Toruń, 7 Gagarin St., 87-100 Toruń, Poland.
Foods. 2023 Jun 24;12(13):2474. doi: 10.3390/foods12132474.
Caffeine is a natural psychoactive substance that belongs to a group of chemical compounds called purine alkaloids. Caffeine is found in various plants such as coffee, tea, cocoa, guarana, and yerba mate. It is often added to dietary supplements for its ability to increase metabolism and aid in weight loss. To determine the caffeine content in dietary supplements, a novel UHPLC method was developed, compatible with the rules of green analytical chemistry. The developed method used only water and ethanol for sample preparation and chromatographic separation on a short C18 column. The obtained method confirmed that caffeine may be analyzed using only environmentally friendly solvents, ethanol, and water. The developed method is characterized by its low limit of quantitation, equal to 0.047 µg/mL, and good reproducibility (a relative standard deviation lower than 1.1%). The obtained results show that the caffeine content in tested dietary supplements is 4-35% higher than the declared amount in most cases. In comparison, the caffeine content of the drug determined using this method was performed with an accuracy of 0.4% RSD.
咖啡因是一种天然的精神活性物质，属于一类称为嘌呤生物碱的化合物。咖啡因存在于各种植物中，如咖啡、茶、可可、瓜拉那和马黛茶。由于其具有提高新陈代谢和辅助减肥的能力，它常被添加到膳食补充剂中。为了测定膳食补充剂中的咖啡因含量，开发了一种新型超高效液相色谱（UHPLC）方法，该方法符合绿色分析化学的规则。所开发的方法在短C18柱上进行样品制备和色谱分离时仅使用水和乙醇。所获得的方法证实，仅使用环保型溶剂乙醇和水就可以分析咖啡因。所开发的方法具有低定量限，等于0.047 µg/mL，以及良好的重现性（相对标准偏差低于1.1%）。所获得的结果表明，在大多数情况下，受试膳食补充剂中的咖啡因含量比宣称的量高
Zotero 插件