提出了超高效液相色谱法-电化学检测器(UHPLC-ECD)同时测定大血藤样品中羟基酪醇、原儿茶酸、红景天苷、酪醇、儿茶素、隐绿原酸、绿原酸、表儿茶素含量的方法。称取大血藤样品粉末约1 g,过0.42 mm筛,用30 mL 30%(体积分数)甲醇溶液超声提取10 min,离心,提取液经0.22 μm滤膜过滤后进样分析。以Waters ACQUITY UPLC^® BEH Shield RP18色谱柱为固定相,以不同体积比的乙腈-50 mmol·L^-1柠檬酸盐缓冲液(pH 2.76)为流动相进行梯度洗脱;设置ECD库仑检测池的第一通道检测电压为350 mV (用于检测羟基酪醇、原儿茶酸、儿茶素、隐绿原酸、绿原酸、表儿茶素),第二通道检测电压为600 mV (用于检测红景天苷、酪醇)。结果显示:8种化学成分的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0.7~8.5 μg·L^-1;对混合标准溶液或样品溶液进行精密度(n=6)、稳定性(n=7)试验,各目标物峰面积的相对标准偏差均小于5.0%;对实际样品进行加标回收试验,回收率为96.0%~102%。方法用于不同产地的24批大血藤样品分析,其中S15和S18样品中红景天苷和绿原酸均不符合要求。

A method for the simultaneous determination of hydroxytyrosol, protocatechuic acid, salidroside, tyrosol, catechin, cryptochlorogenic acid, chlorogenic acid and epicatechin in Sargentodoxa cuneata by ultra-high performance liquid chromatography (UHPLC) combined with electrochemical detector (ECD) was proposed. The Sargentodoxa cuneata sample powder about 1 g was passed through 0.42 mm sieve, and extracted ultrasonically with 30 mL of 30% (φ) methanol solution for 10 min. After centrifugation, the extract was filtered through 0.22 μm membrane for analysis. Waters ACQUITY UPLC^® BEH Shield RP18 column was used as the stationary phase, and a mixture of acetonitrile and 50 mmol·L^-1 potassium citrate buffer (pH 2.76) at different volume ratios was used as the mobile phase for gradient elution. The detection potential of Coulomb detection pool of ECD was 350 mV in the first channel for hydroxytyrosol, protocatechuic acid, catechin, cryptochlorogenic acid, chlorogenic acid and epicatechin, and 600 mV in the second channel for salidroside and tyrosol. As shown by the results, linear relationships between values of mass concentration and peak area of 8 chemical components were kept in the definite ranges, with detection limits (3S/N) in the range of 0.7-8.5 μg·L^-1. Tests for precision (n=6) and stability (n=7) were carried out on the mixed standard solution or sample solution, and RSDs of the peak areas of target compounds were less than 5.0%. Test for recovery was made on the actual sample, giving results in the range of 96.0%-102%. This method was applied to analysis for the 24 batches of Sargentodoxa cuneata samples from different origins, salidroside and chlorogenic acid in S15 and S18 samples did not meet the requirements.