尿液碘两点速率法的建立及评价

Establishment and evaluation of two-point rate assay for urinary iodine

目的用尿液碘快速测定商品试剂,建立全自动生化分析仪检测尿液碘的两点速率法,并评估其检测性能。方法根据碘催化过氧乙酸氧化3,3',5,5'-四甲基联苯胺(TMB)的化学反应原理及全自动生化分析仪的工作特点,改变尿液碘快速测定商品试剂,建立尿液碘两点速率法,分析其线性范围、回收率、最低检测限和精密度,并与原试剂盒手工定量比色法进行相关及偏倚分析。结果建立了全自动生化分析仪检测尿液碘的两点速率法。该法线性范围为0～318.0μg/L;最低检测限为1.14μg/L;批内变异系数(CV)均值为2.57%,批间CV均值为2.27%,日间CV均值为1.94%,总CV均值为2.83%;平均回收率为97.48%。用本法与手工定量比色法分别检测40份尿液标本,结果相关性良好(r2=0.982,P<0.01)。结论成功建立了用全自动生化分析仪检测尿液碘的两点速率法,其线性范围宽,回收率、精密度、相关性及偏倚均符合要求,适于临床应用。

Objective To establish a two-point rate assay using rapid determination commercial kit to measure the level of urinary iodine in fully automatic biochemical analyzer,and evaluate its performance.Methods According to the principle of chemical reaction that peracetic acid oxidizes 3,3′,5,5′-tetramethylbenzidine（TMB） catalyzed by iodine,and the operating features of the fully automatic biochemical analyzer,the rapid determination commercial kit of urinary iodine was improved and two-point rate assay for urinary iodine level was established.The linearity,recovery experiment,lower detection limit and the precision of the method were evaluated.The correlation and the bias between the evaluated method and the originally manual quantitative colorimetric measurement were analyzed.Results The two-point rate assay for determination of urinary iodine level in automatic biochemical analyzer was developed.The developed method was linear from 0 to 318.0 μg/L and the lowest limit was 1.14 μg/L.The mean values of within-run,between-run,between-day and total coefficients of variation（CV） were 2.57%,2.27%,1.94% and 2.83%,respectively.The mean recovery rate was 97.48%.Forty urine samples were determined by the two-point rate assay and manual colorimetric assay simultaneously.The results showed good correlation（r2=0.982,P0.01） between the two methods.Conclusion The two-point rate assay for urinary iodine with automatic biochemical analyzer was successfully established which showed wide linear range,high recovery rate,perfect precision,good correlation and acceptable bias.The established method may meet the requirements of clinical application.