高效液相色谱法测定化妆品中对羟基苯甲酸甲酯含量的不确定度评定

Evaluation of uncertainty in determination of methyl p-hydroxybenzoate in cosmetics by high performance liquid chromatography

评定高效液相色谱法测定化妆品中对羟基苯甲酸甲酯的不确定度。依据国家计量技术规范JJF 1059.1—2012《测量不确定度评定与表示》,通过建立数学模型量化不确定度分量,计算合成不确定度和扩展不确定度。结果表明,当取置信概率为95%,包含因子k=2时,高效液相色谱法测定化妆品中对羟基苯甲酸甲酯含量的扩展不确定度为36.20μg/g,测量结果表示为(2026.32±36.20)μg/g。高效液相色谱法测定化妆品中对羟基苯甲酸甲酯的不确定度主要来源于标准物质称量及系列标准溶液配制。

Measurement uncertainty was evaluated for the determination of methyl p-hydroxybenzoate in cosmetics by high performance liquid chromatography.The sources of uncertainty were analyzed according to the national measurement technical specification JJF 1059.21–2012 Evaluation and Expression of Uncertainty in Measurement.The combined uncertainty and extended uncertainty were calculated by establishing mathematical model.The results showed that when the confidence level was 95%and the coverage factor k was 2,the expanded uncertainty for the determination of methyl p-hydroxybenzoate in cosmetics by high performance liquid chromatography was 36.20μg/g.The measurement result was expressed as(2026.32±36.20)μg/g.The uncertainty of determination of methyl p-hydroxybenzoate in cosmetics by high performance liquid chromatography mainly comes from standard material weighing and standard curve preparation.