离子液体修饰的磁性类沸石咪唑酯骨架材料在藻毒素分析中的应用

采用基于离子液体修饰的类沸石咪唑酯磁性复合纳米材料(IL@M/ZIF-8)的磁性固相萃取(MSPE)前处理技术,结合超高效液相色谱-三重四极杆串联质谱法(UPLC-MS/MS)测定环境水体中痕量微囊藻毒素MC-RR和MC-LR的浓度水平。以扫描电镜和透射电镜对合成材料进行表征,并对UPLC-MS/MS条件和MSPE技术中吸附剂用量、水样pH值、洗脱溶剂的种类、振荡时间等参数进行优化。在最佳条件下,MC-RR和MC-LR分别在0.01~5μg/L和0.05~5μg/L浓度范围内呈良好线性,线性系数(r)分别为0.9995、0.9993,检出限分别为1.98、3.94ng/L,定量下限分别为6.52、12.98ng/L。将该方法应用于实际水样的测定,加标回收率为88.5%~108%,相对标准偏差为1.5%~7.2%。该方法操作简单,灵敏度高,可用于水样中痕量微囊藻毒素的检测。

Application of Ionic Liquid Modified Magnetic Zeolitic Imidazolate Framework Material in Analysis of Microcystins

A method was developed for the determination of trace amount of MC-RR and MC-LR in surface water by ultra performance liquid chromatography-mass spectrometry (UPLC-MS/MS )combined with magnetic solid-phase extraction (MSPE ) based on ionic liquid modified magnetic zeolitic imidazolate framework material (IL@M/ZIF-8 ).The synthesized material was characterized by scanning electron microscopy (SEM ) and transmission electron micorscopy (TEM ).The experimental conditions in MSPE and UPLC-MS/MS,including dosage of adsorbent,pH value,type of elution solvent and oscillation time were optimized.Results showed that,under the optimal conditions,there were good linear relationships for MC-RR and MC-LR in the ranges of 0.01-5 μg/L and 0.05-5 μg/L,with their correlation coefficients ( r ) of 0.999 5 and 0.999 3,respectively.The detection limits were 1.98,3.94 ng/L,and the quantitation limits were 6.52,12.98 ng/L,respectively.The method was applied in the analysis of microcystins in water with spiked recoveries of 88.5 %-108 % and relative standard deviations of 1.5 %-7.2 %.The method could be used for the detection of trace microcystins in water samples owing to its simplicity and high sensitivity.