基于加速器质谱测量的^(14)C呼气试验样品制备方法研究

Samples Preparation of Breath Test ^(14)C Tracer for Accelerator Mass Spectrometry

采用加速器质谱法研究^(14)C呼气试验样品的制备方法。采用长寿命放射性核素^(14)C作为示踪核素,目前已广泛应用于生物代谢、疾病诊断和脏器功能评估。离子源引出的束流强度是衡量加速器质谱灵敏度的重要参数,为了获得较高的束流强度,本工作系统研究了^(14)C呼气试验样品的石墨法、碳酸盐法两种制备方法,拟建立^(14)C呼气试验样品制备流程,确定最高束流强度引出时的最优^(14)C呼气试验样品制备参数,为^(14)C呼气试验广泛应用提供实验基础。

Carbon plays an important role in the metabolism of plants and human.Radiocarbon（14C）is an ideal tracer for vivo human metabolism,disease diagnosis and organ function assessment studies.In this paper,the preparation method of 14C breath test samples for accelerator mass spectrometry（AMS）measurement was developed in China.AMS,with its advantages of high sensitivity,small radioactivity dose,high precision,large measuring range,and long tracer cycle,can be used to measure cosmogenic nuclide 14C,which has long half-life.The current intensity of interested ion in ion source is an important parameter for the sensitivity of AMS measurement.The high beam current can improve the sensitivity of AMS.The preparation methods of breathtest samples of 14C tracer were systematically studied to obtain high beam current using graphitization and carbonatization methods.A reliable preparation procedure of breath test samples for 14C tracer and its optimization parameters were determined by testing beam currents of various samples,which has laid a foundation for 14C-AMS technology at breath test tracer application.