电感耦合等离子体质谱法分析小鼠组织中以及和DNA结合的贫铀浓度与^(235)U/^(238)U  

Determination of Depleted Uranium and ^(235)U/^(238)U of Tissues and Combined with DNA in Mouse by Inductively Coupled Plasma Mass Spectrometry

作　　者：郭志英[1] 梁月琴[1] 崔晓磊[1] 于水[1] 

机构地区：[1]军事医学科学院生物医学分析中心,北京100850

出　　处：《分析化学》2012年第12期1865-1870,共6页Chinese Journal of Analytical Chemistry

基　　金：国家科技部创新方法研究项目(No.2008IM021500);国家自然科学基金项目(No.81102072);第47批博士后基金项目(No.20100471003)资助

摘　　要：在DU染毒动物模型基础上,采用ICP-MS技术同时测定各组织中铀浓度和235U/238U比值,分析DU在体内的分布和代谢规律;提取纯化肝肾组织中的基因组DNA,ICP-MS检测与DNA结合的DU浓度和235U/238U。以Pt为内标元素,补偿基体效应,组织中铀的检出限为0.0019～0.0981μg/kg;精密度(RSD)为0.92%～2.13%,回收率在100%±10%内。ICP-MS对贫铀气溶胶中235U/238U检测结果与经典的α谱仪检测结果相吻合。DNA样品采用中性溶液稀释,DNA中铀元素检出限为0.0016μg/kg DNA,回收率为98.3%±7.3%。样本测定结果显示,肾脏和骨骼对贫铀的蓄积能力最强,脑组织几乎不受贫铀影响,其它组织的DU蓄积能力介于二者之间。在肾、肝组织中,DU可以与DNA发生结合,与肾DNA结合更持久。组织中235U/238U随染毒铀同位素组成和浓度发生规律性改变。铀浓度与235U/238U均可以作为衡量核素污染类型和程度的敏感指标。The BALB/c mice was exposed to deplete uranium（DU） solution（235U/238U=0.00431）.Blood and the tissues of kidney,liver,spleen,cerebrum,femur,lung and testicle were collected in different time after the exposion.The uranium concentration and 235U/238U ratio in tissues were determined simultaneously by inductively coupled plasma mass spectrometry（ICP-MS）,and to analyze the distribution and metabolism of DU in the body.The extracted and purified genomic DNA in kidney and liver was dialyzed to excluding the DU uncombined,and quantified by ultraviolet spectrophotometry.Then the DNA was diluted with special diluents,and the binding level of DU with genomic DNA in kidney and liver was detected by ICP-MS.Pt was confirmed as the internal standard to compensate matrix influence.The limits of detection in tissues were in the range of 0.0019 μg/kg to 0.0981 μg/kg.The precision（RSD） ranged from 0.9% to 2.1%,and the recovery was about 100%±10%.The results of 235U/238U isotopic ratio in the depleted uranium aerosols detected by ICP-MS were consistent with the results detected by α-spectrometer,and RSD=6%.The genomic DNA was diluted with neutral solution.The detection limit of uranium in DNA was 0.0016 μg/kg,and the recovery was 98.3%±7.3%.The analytical results showed that DU could be differentially accumulated in different tissues,and most of DU was accumulated in kidney and bone,and scarcely enter into the brain tissue.Especially,DU would be accumulated in bone for a long time.DU could combine with genomic DNA in kidney and liver,and the binding level of DU in kidney was relatively high and persistent.The uranium concentration in tissues had relationship to some extent with 235U/238U,and the 235U/238U isotopic ratio would be altered with uranium concentration.The uranium concentration and 235U/238U can be sensitive indicator to measure the pollution of uranium.

关 键 词：电感耦合等离子体质谱 贫铀 235U 238U DNA 

分 类 号：R346[医药卫生—基础医学] O657.63[理学—分析化学]