毛发中铀的二次离子质谱分析研究

毛发对人体微量元素有一定的蓄积效应，且作为一种无创生物检材，在核取证、环境监测、职业暴露检测、医学等领域逐渐受到重视。目前，大多采用整体分析技术测量毛发中元素的平均含量，毛发微区分析相关研究较少。为拓展毛发分析方法应用，本研究通过喂养大鼠硝酸铀酰溶液的方式获得含铀量较高的鼠毛样品，对毛发样品预处理方法、毛发中铀的二次离子质谱（SIMS）测量方法开展研究。结果表明，使用SIMS测量毛发时，样品靶表面刻槽能有效提升信号强度稳定性；样品表面镀铜能有效降低表面电荷积累并减少多原子离子对铀离子信号干扰。使用多接收电感耦合等离子体质谱仪（MC-ICP-MS）和SIMS对鼠毛中铀分布、平均铀含量及同位素比进行测量。结果表明，该方法能有效判断大鼠是否摄铀，分辨大鼠摄铀类型。本研究可为毛发样品溯源分析提供技术支持，对毛发中微量元素的分析研究具有重要意义。

Study on the Analysis of Uraniumin Rat Hair by Secondary Ion Mass Spectrometry

Hair samples,as a non-invasive biological material,it is gradually gaining attention in the fields of nuclear forensics,environmental monitoring,occupational exposure detection,and medicine due to its certain accumulation effect on human trace elements.At present,in the field of hair analysis,most of the existing researches use the bulk analysis technology to measure the average content of elements in hair,while there are few researches on hair micro-area analysis.In order to expand the application of hair analysis methods,the rat hair samples with high uranium content were obtained by feeding rats with uranyl nitrate solution.The pretreatment method of hair samples and the measurement method of uranium in hair by secondary ion mass spectrometer(SIMS)were studied.The results show that when measuring hair samples using SIMS,the grooves on the surface of the sample target can effectively improve the signal strength stability;coating copper on the sample surface can effectively reduce the surface charge accumulation and reduce the interference of polyatomic ion signal to uranium ion signal.The distribution,average content and isotope ratio of uranium in rat hair were measured by multi collected inductively coupled plasma mass spectrometry(MC-ICP-MS)and SIMS.The results show that this method can effectively judge whether rats drink uranium solution or not,and distinguish the type of uranium taken by rats.This study provides technical support for traceability analysis of hair samples,which is of great significance for the analysis of trace elements in hair.