本研究旨在建立一种高效、快速、选择性测定食品中痕量汞的方法。通过溶剂热法及后续的巯基化修饰,成功制备了一种新型巯基功能化磁性介孔二氧化硅(Thiol-functionalized Magnetic Mesoporous Silica,记为mSS@Fe_(3)O_(4))吸附剂。将该...本研究旨在建立一种高效、快速、选择性测定食品中痕量汞的方法。通过溶剂热法及后续的巯基化修饰,成功制备了一种新型巯基功能化磁性介孔二氧化硅(Thiol-functionalized Magnetic Mesoporous Silica,记为mSS@Fe_(3)O_(4))吸附剂。将该吸附剂用于磁性固相萃取(MSPE),结合原子荧光光谱法(AFS),构建了一种分析食品中痕量汞的新方法。通过X射线衍射(XRD)、傅里叶变换红外光谱(FTIR)和X射线光电子能谱(XPS)等手段对材料进行了表征,证实了巯基已成功接枝到磁性介孔二氧化硅表面。系统优化了萃取过程中的关键参数,包括样品pH值、吸附时间、吸附剂用量、洗脱液组成和上样体积。结果表明,归因于材料的介孔结构和高比表面积,吸附平衡在1 min内即可达到,实现了对Hg^(2+)的快速富集。在最优条件下,该吸附剂对Hg^(2+)的理论最大吸附容量(qm)为67.89 mg/g;在回收率保持>90%时,最大上样体积为200 mL,预浓缩因子可达200。该方法具有较宽的pH值(1~13)适用范围和优异的抗基质干扰能力。方法线性范围为0.10~4.0μg/L(相关系数r=0.9996),方法检出限(MDL)为0.012μg/kg,对空白样品进行7次平行测定的相对标准偏差(RSD)为2.4%(n=7)。通过对国家标准物质和多种实际样品(草鱼、大米等)的加标回收实验,验证了方法的准确性和可靠性,回收率在94.0%~106%。该方法集快速、高效、高选择性与高灵敏度于一体,为食品中痕量汞的常规监测提供了有力的技术支持。展开更多
At present,there is currently a lack of unified standard methods for the determination of antimony content in groundwater in China.The precision and trueness of related detection technologies have not yet been systema...At present,there is currently a lack of unified standard methods for the determination of antimony content in groundwater in China.The precision and trueness of related detection technologies have not yet been systematically and quantitatively evaluated,which limits the effective implementation of environmental monitoring.In response to this key technical gap,this study aimed to establish a standardized method for determining antimony in groundwater using Hydride Generation–Atomic Fluorescence Spectrometry(HG-AFS).Ten laboratories participated in inter-laboratory collaborative tests,and the statistical analysis of the test data was carried out in strict accordance with the technical specifications of GB/T 6379.2—2004 and GB/T 6379.4—2006.The consistency and outliers of the data were tested by Mandel's h and k statistics,the Grubbs test and the Cochran test,and the outliers were removed to optimize the data,thereby significantly improving the reliability and accuracy.Based on the optimized data,parameters such as the repeatability limit(r),reproducibility limit(R),and method bias value(δ)were determined,and the trueness of the method was statistically evaluated.At the same time,precision-function relationships were established,and all results met the requirements.The results show that the lower the antimony content,the lower the repeatability limit(r)and reproducibility limit(R),indicating that the measurement error mainly originates from the detection limit of the method and instrument sensitivity.Therefore,improving the instrument sensitivity and reducing the detection limit are the keys to controlling the analytical error and improving precision.This study provides reliable data support and a solid technical foundation for the establishment and evaluation of standardized methods for the determination of antimony content in groundwater.展开更多
基金supported by the National Natural Science Foundation of China(Project No.42307555).
文摘At present,there is currently a lack of unified standard methods for the determination of antimony content in groundwater in China.The precision and trueness of related detection technologies have not yet been systematically and quantitatively evaluated,which limits the effective implementation of environmental monitoring.In response to this key technical gap,this study aimed to establish a standardized method for determining antimony in groundwater using Hydride Generation–Atomic Fluorescence Spectrometry(HG-AFS).Ten laboratories participated in inter-laboratory collaborative tests,and the statistical analysis of the test data was carried out in strict accordance with the technical specifications of GB/T 6379.2—2004 and GB/T 6379.4—2006.The consistency and outliers of the data were tested by Mandel's h and k statistics,the Grubbs test and the Cochran test,and the outliers were removed to optimize the data,thereby significantly improving the reliability and accuracy.Based on the optimized data,parameters such as the repeatability limit(r),reproducibility limit(R),and method bias value(δ)were determined,and the trueness of the method was statistically evaluated.At the same time,precision-function relationships were established,and all results met the requirements.The results show that the lower the antimony content,the lower the repeatability limit(r)and reproducibility limit(R),indicating that the measurement error mainly originates from the detection limit of the method and instrument sensitivity.Therefore,improving the instrument sensitivity and reducing the detection limit are the keys to controlling the analytical error and improving precision.This study provides reliable data support and a solid technical foundation for the establishment and evaluation of standardized methods for the determination of antimony content in groundwater.
