免疫磁珠捕获富集结合HPLC-Q-TOF/MS技术分析复杂水样中的蓖麻毒素

Analysis of Ricin in Complex Water Matrices by Magnetic Immunocapture Enrichment and HPLC-Q-TOF/MS

以自来水、海水以及国际禁化武组织（OPCW）官方水平考试水样为背景基质,在优化仪器参数的基础上,建立了3种水样基质中蓖麻毒素的高效液相色谱-四极杆/飞行时间质谱（HPLC-Q-TOF/MS）分析方法。蓖麻毒素在3种基质中的检出限分别为0.05,0.20,1.00μg/m L,HPLC-Q-TOF/MS测得蓖麻毒素的分子量为62 884.97 Da。为提高复杂水样的分析灵敏度,采用连接有蓖麻毒素单克隆抗体6A6的免疫磁珠对不同水样中的蓖麻毒素进行富集与纯化,利用酶联免疫吸附（ELISA）法绘制了免疫磁珠捕获方法的工作曲线,在5.00~100μg/m L线性范围内,不同浓度加标样品的回收率为82.1%~88.8%,相对标准偏差为4.2%~5.9%。将免疫捕获技术与HPLC-Q-TOF/MS分析方法相结合,对真实蓖麻毒素加标样品进行分析,3种基质中蓖麻毒素的检出限分别达2.5,10,50 ng/m L。本方法可用于水样中痕量蓖麻毒素的快速、有效检测。

Selecting tap water, sea water and the Organisation for the Prohibition of Chemical Weap- ons （OPCW） official test water as background matrices, a high performance liquid chromatography - quadrapole time - of - flight mass spectrometric （ HPLC - Q - TOF/MS） method was developed for the determination of ricin on the base of instrumental parameter optimization. The limits of detection （LODs） of ricin were 0. 05, 0. 20 and 1.00 μg/mL for the three matrices, respectively. The rela- tive molecular mass of ricin was determined to he 62 884.97 Da. In order to improve the analytical sensitivity of complex water samples, immunocapture with magnetic beads linked by anti-ricin mono- clonal antibody 6A6 was adopted to enrich and purify ricin in different water samples. ELISA was used to draw the standard curve of immunocapture. The method showed a good linearity for ricin in the concentration range of 5.00 - 100 μg/mL. The average recoveries at spiked levels of 15, 30 μg/mL were in the range of 82. 1% -88.8% with RSDs of 4. 2% -5.9%. The HPLC -Q - TOF/MS meth- od with immunocapture was applied in the determination of ricin spiked in different matrices. The LODs for ricin in the three different matrices reached to 2.5, 10, 50 ng/mL, respectively. The re- sults demonstrated that the method could be rapidly and effectively used in the determination of trace riein in water samples.