The popularity of energy beverages among young adult population is high. These drinks are claimed to boost energy and performance and contain high concentration of caffeine as one of the several ingredients. Discrepancies have been encountered by some of the previous studies between the actual quantity of caffeine present in the product and the amount mentioned on the label, making the determination of caffeine content in these drinks very important. Thus, in this study, we analyzed the caffeine concentration in most popular energy drinks available in Saudi Arabia. The energy drink samples (n = 9) were procured from retail outlets. Sample solutions were prepared in methanol and analyzed for caffeine content by GC-MS. Chromatographic parameters were optimized to achieve optimum resolution and various validation parameters were evaluated. The method was successfully applied for the quantification of caffeine in energy drinks by directly injecting the multifold diluted samples in methanol. The method was linear (r² = 0.999) over a concentration range of 5–25 µg/mL, specific, precise (%RSD of peak area = 0.56–0.78), and accurate (%recovery = 99.3–101.2%). The amounts of caffeine determined were found in the range of 20.82–33.72 mg/100 mL (52.05–84.3 mg/pack). Results revealed that the amount of caffeine actually present in the tested drinks varied within ±10% range from the amount specified on the product labels. The amounts of caffeine detected in tested beverages were within the USFDA safe upper limit of per-day caffeine consumption, which has indicated that the consumption of one serving of energy drink is unlikely to produce any adverse health effect.

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气相色谱-质谱法测定沙特阿拉伯市场上商用能源饮料中的咖啡因含量

能量饮料在年轻人中的流行很高。这些饮料据称可提高能量和性能，并含有高浓度的咖啡因作为几种成分之一。先前的一些研究发现产品中咖啡因的实际数量与标签上提及的数量之间存在差异，因此确定这些饮料中咖啡因含量非常重要。因此，在这项研究中，我们分析了沙特阿拉伯最流行的能量饮料中的咖啡因浓度。能量饮料样品（n = 9）从零售店采购。样品溶液在甲醇中制备，并通过GC-MS分析咖啡因含量。优化色谱参数以获得最佳分离度，并对各种验证参数进行了评估。通过直接将多重稀释的样品直接注入甲醇，该方法成功地用于定量能量饮料中的咖啡因。该方法在 5–25 µ浓度范围内是线性的（r ² = 0.999） g / mL，特异，精确（峰面积的％RSD = 0.56-0.78）和精确（回收率％= 99.3-101.2％）。测定的咖啡因含量范围为20.82–33.72 mg / 100 mL（52.05–84.3 mg /包）。结果表明，测试饮料中实际存在的咖啡因含量与产品标签上指定的含量相差±10％。在测试的饮料中检测到的咖啡因含量在USFDA每天摄入咖啡因的安全上限之内，这表明食用一份能量饮料不太可能对健康产生任何不利影响。