双柱净化-高效液相色谱法测定水源水中微囊藻毒素

Determination of microcystins in source water by double solid phase extraction coupled with high performance liquid chromatography

目的 优化水源水中2种微囊藻毒素(MC-LR和MC-RR)的双柱净化-高效液相色谱分析方法,去除水源水中的干扰物质,减少原有方法检出的假阳性及假阴性的概率并用于水样的实际测定。方法 样品滤液和乙酸提取藻细胞液体合并后,经HLB固相萃取柱富集洗脱,经氮吹至近干后,用甲醇定容至1. 0 ml,定容液经SLH固相萃取柱净化,经甲醇淋洗,甲醇(含0. 1%三氟乙酸)洗脱,洗脱液吹至近干,流动相定容至1. 0 ml,进样分析。结果 MC-LR和MC-RR的线性范围为0. 30μg/L~5. 00μg/L,线性相关系数≥0. 999 7,检出限为0. 10μg/L~0. 13μg/L,加标浓度为0. 30μg/L~5. 00μg/L时,平均回收率为83. 39%~108. 1%;相对标准偏差(RSD)为1. 45%~8. 69%(n=6)。结论 该法对检测用仪器要求不高、干扰少、准确率高,适用于基层单位对水源水等杂质较多水样中微囊藻毒素的检测。

Objective Two kinds of microcystins(MC-LR,MC-RR)in source water were analyzed by double-column purification and high performance liquid chromatography(HPLC)to remove the interfering substances in source water,reduce the probability of false positive and false negative detected by the original method,and applied to the actual determination of water samples.Methods After the sample filtrate was mixed with acetic acid extracted algal cell liquid,it was enriched and eluded by HLB solid phase extraction column.After being blown to near dry by nitrogen,it was quantified to 1.0 ml with methanol.The constant volume solution was purified by SLH solid phase extraction column,eluted by methanol(containing 0.1% trifluoroacetic acid),the eluent was blown to near dry,the mobile phase was constant volume to 1.0 ml,and the sample was analyzed.Results The linear range of MC-LR and MC-RR ranged from 0.30 μg/L to 5.00μg/L,and the linear correlation coefficient was ≥0.9997.The detection limits were from 0.10μg/L to 0.13μg/L.The average recoveries were 83.39%to 108.1% when the spiked concentration was from 0.30μg/L to 5.00 μg/L.The relative standard deviations(RSD)were 1.45%-8.69%(n=6).Conclusion The established method was sensitive,selective and accurate,and suitable for the determination of microcystins in source water with more interferon.