原子荧光光谱法测定化妆品中总砷不确定度的评定

The Total Arsenic in Cosmetics Uncertainty by Atomic Fluorescence Spectrometry

目的探讨原子荧光光谱法测定化妆品中总砷不确定度。方法通过建立原子荧光光谱法测定总砷的数学模型,寻找不确定度的主要来源。结果该化妆品中砷含量为0.134 mg/kg,其扩展不确定度为0.014 mg/kg;由标准曲线拟合产生的不确定度最大,其次是标准使用液配制产生的不确定度。结论每年需对仪器进行定期检测,以确保仪器处于良好稳定状态;此外,为了降低曲线配制带来的不确定度影响,应减少砷标准溶液稀释步骤,并尽量购买相对浓度较低的标准溶液。

Objective To investigate the atomic fluorescence spectrometric determination of total arsenic in cosmetics uncertainty.Methods Through the establishment of mathematical model of determination of arsenic by atomic fluorescence spectrometry,find the main source of uncertainty.Results The content of arsenic in cosmetics was 0.134 mg/kg,the expanded uncertainty is 0.014 mg/kg;produced by the standard curve of the uncertainty of the largest,followed by the uncertainty of standard solution generated.Conclusion Each year for regular testing of instruments,to ensure that the instruments in good steady state;in addition,in order to reduce the curve preparation the uncertain degree of influence,should try to reduce arsenic standard solution dilution steps and try to buy relatively low concentration of standard solution.