ALT和AST参考方法的建立与性能评价

Establishment and evaluation of the reference methods of alanine aminotransferase and aspartate aminotransferase

目的建立测定血清丙氨酸氨基转移酶(ALT)和天门冬氨酸氨基转移酶(AST)的参考方法,并评价其主要分析性能。方法按照国际临床化学与检验医学联合会(IFCC)有关ALT和AST活性测定的要求建立参考方法,并优化其实验条件;根据美国临床实验室标准化委员会(NCCLS)系列文件(EP5-A2、EP15-A、EP6-A)对建立的参考方法的精密度、准确度、线性范围等性能进行评价。结果紫外分光光度计、分析天平、pH计、电子温度计、移液器和容量瓶均检定合格,不确定度符合方法要求。温控器显示为37.2℃时,比色杯内溶液温度最接近37℃;比色杯内溶液180 s后可达到设定温度;移液器加样模式实验显示吸一档打两档,打时靠壁为精密度最佳的加样模式。ALT和AST参考方法的批内不精密度均<1%,总不精密度均<2%,符合精密度性能要求;日本临床化学会酶参考品及国际参考实验室外部质量评价计划样本检测结果的相对偏倚均符合设定目标;ALT和AST参考方法分析测量范围上限分别为335.8、363.6 U/L,均高于IFCC文献报道。结论ALT和AST参考方法已基本建立,精密度、准确度及线性范围等性能指标均符合方法要求,可应用于临床研究。

Objective To establish the reference methods of alanine aminotransferase（ALT） and aspartate aminotransferase（AST）and evaluate their analytic characteristic.Methods The reference methods were established according to relative documents of International Federation of Clinical Chemistry（IFCC）,and the measurement condition was optimized.Furthermore,the precision,accuracy and linearity range of the methods were evaluated according to the evaluation protocols of National Committee for Clinical Laboratory Standards（Document EP5-A2,EP15-A and EP6-A）.Results Ultraviolet spectrophotometer,analytic balance,pH meter,electronic thermometer,pipettes and volumetirc flask had been verified and the uncertainty fit to the method′s requirements.When the temperature controller showed 37.2 ℃,the temperature in cuvette showed 37.0 ℃.The temperature in cuvette would reach the set temperature after 180 s.The pipettes application of sample model test showed the precision of suction once and turning twice,and anear tube inner wall was best.The within-run imprecision of ALT and AST reference methods was less than 1%,and the total imprecision was less than 2%.The biases of enzyme reference material（ERM） produced by Japanese Committee for Clinical Laboratory Standards and the samples from external quality control of reference labortories were all within the limit of requirements.The upper limits of the measurement ranges of ALT and AST were 335.8 and 363.6 U/L respectively,which were both higher than those of IFCC reporting.Conclusions The reference methods have been established basically.Most analytic characteristics such as precison,accuracy and linear range were conform to requirements.The established reference methods can be used for clinical research.