取10 g饮料样品,加水稀释并定容至50 mL,混合均匀,取少量混合液以转速10 000 r·min^-1离心10 min,上清液经0.22 μm滤膜过滤后,以ACQUITY UPLC^® BEH C₁₈色谱柱为固定相,电化学检测器(ECD)检测,检测池电压为650 mV,采用超高效液相色谱法测定其中爱德万甜、根皮苷、柚皮苷二氢查耳酮、三叶苷、新橙皮苷二氢查耳酮、根皮素的含量。结果表明,爱德万甜和5种二氢查耳酮类甜味剂在9.0 min内可以完全分离,其质量浓度在一定范围内与其对应的峰面积呈线性关系,检出限(3S/N)为2.1~6.8 μg·L^-1。按标准加入法进行回收试验,回收率为97.1%~105%,测定值的相对标准偏差(n=6)为1.4%~5.1%。与二极管阵列检测器(DAD)比较,使用ECD时,灵敏度高、检出限低。与其他文献方法相比,本方法的灵敏度、分析时间均具有明显优势。

The drink sample (10 g) was taken, diluted with water and made its volume up to 50 mL. After fully mixing, a small amount of solution was taken and centrifuged for 10 min at a rotating speed of 10 000 r·min^-1. Then the supernatant was filtered by 0.22 μm filtration membrane, and advantame, phlorizin, naringin dihydrochalcone, trilobatin, neohesperidin dihydrochalcone and phloretin in the above solution were determined by ultra-high performance liquid chromatography (UHPLC), using ACQUITY UPLC^® BEH C₁₈ column as the stationary phase, and electrochemical detector (ECD) with the detection cell voltage set at 650 mV. As shown by the results, advantame and 5 sweeteners of dihydrochalcones could be separeted completely within 9.0 min, and linear relationships between values of peak area and mass concentration of advantame and 5 sweeteners of dihydrochalcones were found in definite ranges, with detection limits (3S/N) ranged from 2.1 μg·L^-1 to 6.8 μg·L^-1. Test for recovery was made by standard addition method, giving results in the range of 97.1%-105%, with RSDs (n=6) of the determined values in the range of 1.4%-5.1%. Compared with diode array detector (DAD), ECD had higher sensitivity and lower detection limit. Compared with other methods in the literature, this method had obvious advantages of sensitivity and analysis time.