生物样品中碳-14分析测量方法探讨

Analysis and measurement method for carbon-14 in biological samples

目的对环境生物样品中碳-14测量分析方法进行优化研究,为环境生物样品中碳-14测量标准方法的制定提供技术支持。方法通过对二氧化碳吸收法的优化研究,选用水分测定仪、元素分析仪测量生物样品的含水率、碳元素含量,简化人员操作、优化方法流程步骤,并开展方法实验室内、实验室间验证。结果典型条件下,方法探测下限可达3 Bq/kg,实验室内相对标准偏差小于17%,实验室间相对标准偏差小于14%,相对误差小于19%;样品前处理更多由仪器设备直接完成,提高了样品含水率和碳元素含量测量的精密度和准确度,降低了实验人员操作差异对测试结果的影响。结论优化后的方法探测下限、精密度、正确度等满足生物样品中碳-14测定有关要求。

Objective To optimize the measurement and analysis method for carbon-14 in environmental biological samples,and to provide technical support for the formulation of standard methods for carbon-14 measurement in environmental biological samples.Methods Through the optimization research on the carbon dioxide absorption method,the moisture content and carbon content of biological samples were measured with the moisture meter and the element analyzer according to the simplified personnel operation and the optimized process steps of the method,and intra-and inter-laboratory validation of the method was carried out.Results Under typical conditions,the lower limit of detection of the method reached 3 Bq/kg,and there were a relative standard deviation within laboratories of less than 17%and a relative standard deviation between laboratories of less than 14%,with a relative error of less than 19%.Most of the sample pretreatment was directly completed by the instrument and equipment,which improved the precision and accuracy of the measurement of moisture content and carbon content in samples,and reduced the influence of experiment personnel’s operation differences on the test results.Conclusion The lower limit of detection,precision,and accuracy of the optimized method meet the relevant requirements for the determination of carbon-14 in biological samples.