高效液相色谱法测定鸡蛋中角黄素的不确定度评定

Uncertainty evaluation of the determination of canthaxanthin in eggs by high performance liquid chromatography

中文关键词:  鸡蛋  角黄素  高效液相色谱法  不确定度

英文关键词:eggs  canthaxanthin  high performance liquid chromatography  uncertainty

中文摘要:

      目的 评定高效液相色谱法测定鸡蛋中角黄素含量的不确定度。方法 样品经乙腈水浴超声提取和离心, 取上清液用正己烷脱脂, 再用旋转蒸发仪浓缩后, 乙腈定容, 经C18色谱柱分离, 流动相等度洗脱, 采用高效液相色谱仪(紫外-可见检测器)在波长471 nm进行测定。外标法定量测定鸡蛋中角黄素含量。依据JJF 1135—2005《化学分析测量不确定度评定》和JJF 1059.1—2012《测量不确定度评定与表示》, 考察整个测量过程不确定度来源(如称重、试样定容体积、标准溶液配制、标准曲线拟合、样品重复性和回收率); 并对各个因素引入的不确定度进行计算和合成; 最后给出扩展不确定度。结果 当鸡蛋中角黄素检测结果为0.39 mg/kg时, 扩展不确定度为0.017 mg/kg, k=2。结论 实验过程中的不确定度主要来源于标准曲线配制、标准曲线拟和样品测量, 需要在测量过程中重点控制进而降低测量结果的不确定度。

英文摘要:

      Objective To evaluate the uncertainty in determination of canthaxanthin in eggs by high performance liquid chromatography. Methods The sample was extracted by acetonitrile in a water bath and centrifuged. The supernatant was degreased with n-hexane, after concentrated with rotary evaporator, the volume was fixed with acetonitrile. The sample was analyzed by chromatography column C18 with fow equivalence elution, the sample was analyzed by high performance liquid chromatography (UV-Vis detector) at the wavelength of 471 nm. The target was quantified with external standard curve. According to JJF 1135—2005 Assessment of uncertainty in measurement of chemical analysis and JJF 1059.1—2012 Assessment and expression of uncertainty in measurement, sources of uncertainty in the whole measurement process were investigated (such as weighing, constant volume of sample, preparation of standard solution, standard curve fitting, sample repeatability and recovery rate). The uncertainty introduced by each factor was calculated and synthesized. Finally, the extended uncertainty was given. Results When the determination result of canthaxanthin in eggs was 0.39 mg/kg, the expand uncertainty was 0.017 mg/kg (k=2). Conclusion The uncertainty in the experimental process mainly comes from standard curve preparation, standard curve fitting and sample measurement. In the process of measurement, it is important to control and reduce the uncertainty of measurement results.