高效液相色谱法测定辣椒粉中碱性橙的不确定度评定

为分析高效液相色谱法测定辣椒粉中碱性橙含量的不确定度，采用JJF 1135-2005《化学分析测量不确定度评定》进行评定。依据检测方法建立数学模型，分析不确定度的重要来源，其中标准溶液配制产生的不确定度是0.008 3，最小二乘法拟合标准曲线校准产生的不确定度是0.056，样品称量带来的不确定度是0.002 5，样品定容带来的不确定度是0.005 0，样品处理过程带来的不确定度是0.012，结果的重复性带来的不确定度是0.022。对各不确定度分量进行分析计算和合成不确定度，通过乘以95%概率下的扩展因子2，获得加标辣椒样品中碱性橙含量测定结果是（30±3.73） mg/kg，最小二乘法拟合标准曲线对测定结果的影响最大，其次样品处理过程和结果的重复性带来的不确定度也不容忽略。

Uncertainty Evaluation for the Determination of Basic Orange in Chili Powder by High Performance Liquid Chromatography

Based on Evaluation of Uncertainty in Chemical Analysis Measurement, the uncertainties in the determination
of basic orange in chili powder by HPLC were evaluated. According to the developed mathematic model, the sources of
uncertainty were analyzed. The uncertainty components affecting the results were evaluated. The uncertainties from the
preparation of standard solution, the calibration of the standard curve fitted by least square regression, the measurement of
the sample weight, the adjustment of the sample volume, sample treatment, and the repeatability of the results were 0.008 3,
0.056, 0.002 5, 0.005 0, 0.012, and 0.022, respectively. The content of basic orange in spiked chili powder was (30 ± 3.73) mg/kg as
obtained by multiplying the combined uncertainty from the uncertainty components by the expansion factor 2 at 95%
possibility. It was also found that the uncertainty from the standard curve fitted by least square regression had the
largest effect on the results, and the uncertainties from sample treatment and the repeatability of the results could not
be overlooked.