Method validation and determination of caffeine in drinks in the Iranian market by the HPLC

Background: Caffeinated energy drinks are common drinks among athletes and general population that have benefits such as providing quick energy, reducing fatigue and creating alertness, but can lead to serious complications in patients, especially those who have cancer and mental, cardiovascular, or renal diseases. The aim of this study was to validate the quantitative analysis and determine caffeine in 10 caffeinecontaining drink samples from Tehran markets using high efficiency liquid chromatography (HPLC). Materials and methods: In this study, first the HPLC method was validated using the sample standard. Then the amount of caffeine in 10 samples of drinks was evaluated. Results: The calibration curve of caffeine was linear in the range of 2-200 ppm and its correlation coefficient was 0.997. The limits of detection and quantification (LOQ and LOD) were 44.65 and 13.39 g/mL respectively. After validating the method, 10 drink samples collected from Tehran were tested for caffeine content. Comparing the results with international standards showed that the caffeine value of these beverages was lower than the standard. Conclusion: This method has the accuracy and efficiency in measuring the caffeine of beverages. Comparing with international standards, the amount of caffeine in the beverages is lower than the standard. Due to the increased consumption of these drinks in the country, measuring caffeine at different times is essential.