【摘要】 目的评定电感耦合等离子体质谱法(inductively coupled plasma mass spectrometry,ICP-MS)测定大豆中硼含量的不确定度。方法采用ICP-MS法测定大豆中硼的含量,结合测定过程建立数学模型,对各影响分量进行不确定度分析,最后得到合成不确定度以及扩展不确定度。结果测得样品中硼含量为24.4 mg/kg,其扩展不确定度为2.3 mg/kg(k=2)。校准曲线拟合、加标回收率、测量重复性、标准系列配制、称样量和消解液定容体积引入的相对标准不确定度分别为3.5%、2.4%、1.7%、0.49%、0.13%和0.06%。结论影响ICP-MS法测定大豆中硼含量不确定度的主要因素是校准曲线拟合、加标回收率和测量重复性,消解液定容体积、称样量等影响相对较小。更多还原

【Abstract】 Objective To evaluate the uncertainty for determination of boron content in soybean by inductively coupled plasma mass spectrometry. Methods The content of boron in soybean was determined by ICP-MS method. Combined with the determination process, a mathematical model was established and the uncertainty of each influencing component was analyzed. Finally, the combined uncertainty and the expanded uncertainty were obtained. Results The boron content of the sample was 24.4 mg/kg, with an expanded uncertainty of 2.3 mg/kg(k=2). The relative standard uncertainties introduced from calibration curve fitting, spiked recovery, measurement repeatability, standard series preparation, sample weight, and constant volume of digestion solution were 3.5%, 2.4%, 1.7%, 0.49%, 0.13%, and 0.06%, respectively. Conclusion The main factors affecting the uncertainty of determination of boron content in soybean by ICP-MS method are calibration curve fitting, standard recovery and repeatability, and the effect of constant volume and sample size of digestion solution is relatively small.更多还原