【摘要】 目的建立适合于不同饮品中的咖啡因含量检测的高效液相色谱方法。方法可乐型饮料、含乳及不含乳的咖啡及茶叶液体制品、咖啡、茶叶及其固体制品等样品用水提取后,不同类型的饮品经过不同的前处理净化方法,经Symmetry Shield C18反相色谱柱(3.9 mm×150 mm×5μm)分离,用二极管阵列检测器检测,保留时间定性,外标法定量分析。结果咖啡因在220 ng/ml~439μg/ml浓度范围内与峰面积呈良好的线性相关,相关系数r=0.9998,以3倍基线噪音信号确定检出量为0.7 ng;不同饮品3水平添加量的平均回收率为90.2%~107%,测定结果的相对标准偏差(RSD)为0.37%~3.8%(n=6)。结论本方法检测灵敏度高,重现性和准确性好,具备科学性以及可操作性,可用于不同饮品中咖啡因含量的测定。更多还原

【Abstract】 Objective An analytical method of high performance liquid chromatography( HPLC) was established for the determination of caffeine in drinks. Methods The samples including cola beverage,coffee and tea etc were extracted with water,and the different drinks were purified by different pretreatment methods. The separation was performed on a Symmetry Shield C18column( 3. 9 mm × 150 mm × 5 μm) by HPLC with a diode- array detector( DAD). The qualitation was performed by retention time and the quantification was performed by external standard. Results The calibration curve was linear between the peak area and the concentration in the range of 220 ng /ml ~ 439 μg /ml,and the correlation coefficient was 0. 9998. The detection limit was 0. 7ng by 3 times the baseline noise. The average recoveries of different drinks at the three concentration levels were 90. 2%~ 107% with the relative standard deviations of 0. 37% ~ 3. 8%( n = 6). Conclusion The method is sensitive,accurate and reproducible and it has the feasibility and maneuverability. It can be characterized as a reliable method for detection of caffeine in different drinks.更多还原