大肠菌群MPN计数法不确定度评估

Uncertainty evaluation ofcoliform bacteria MPN counting method

中文关键词:  大肠菌群  不确定度评估  MPN法

英文关键词:coliform  uncertainty evaluation  MPN

中文摘要:

      目的 为减少大肠菌群检测中的实验误差, 提高检验精确度, 对大肠菌群MPN计数法不确定度进行评估。方法 使用大肠杆菌标准菌株, 分析大肠菌群检测结果的不确定度来源, 对测定过程中引入的不确定度分量进行评定。采用合成的方法计算检验结果的不确定度。结果 合成不确定度为0.06398, 扩展不确定度为0.1446(以对数计)。大肠杆菌含量范围结果为1212~2358 MPN/mL。结论 本研究发现重复性对不确定度影响最大, 应在分析过程中注意控制。

英文摘要:

      Objective To evaluate the uncertainty of coliform bacteria MPN counting method for reduce experiment error and improve test precision. Methods The standard strains of Escherichia coli was used, and the uncertainty sources of coliform bacteria were analyzed, then the uncertainty components introduced in the experiment were evaluated. Synthetic method was used to calculate the uncertainty. Results The combined uncertainty was 0.06398, and the expanded uncertainty was u(1og)=0.1446. Coliform content was 1212~2358 MPN/mL. Conclusion The results showed that the repeatability was the greatest influence on the uncertainty, and it should be controlled in the test.