对尿碘砷铈催化分光光度测定方法的验证

Verification of an improved method for determination of urinary iodine by As3＋-Ce4＋ catalyticspectrophotometry

目的验证修订后的砷铈催化分光光度方法测定尿碘的可行性及应用价值。方法收集成人1次性尿样备用，制备0～300μg／L和300～1200μg／L的碘标准曲线，应用修订后的砷铈催化分光光度方法测定尿碘。对该检测方法的线性关系及范围、最低检测限、精密度和准确度进行验证，评价验证结果。结果当标准曲线线性范围在0～300“∥L时，最低检出限为1．8μg／L，相关系数为-0．9995—0．9997；测定尿碘浓度为40～80、100～149、200—280“g／L尿样时，相对标准差分别为1．5％、0．8％、0．5％；测定尿碘浓度为40—80、100～149、150—180Izg／L尿样时。加标回收率分别为97．8％、99．8％、96．6％；国家尿碘标准物给定值（标准值±不确定度）为（73．0-4-9．0）、（206±10）μg／L时，测定值为（75．5±0．9）、（207．5-t-1．9）μr,／L，相对偏差分别为3．4％和0．7％，测定结果在不确定度范围内。当标准曲线线性范围为300～1200仙g／L时，最低检出限为305．2μg／L，相关系数为-0．9996—-0．9999；测定尿碘浓度为300～400、500～600、1000～1200μg／L尿样时，相对标准差分别为0．6％、1．O％、0．7％；测定尿碘浓度为300—499、500—599、600～700μg／L尿样时，加标回收率分别为99．7％、99．2％、100．4％；国家尿碘标准物给定值（标准值±不确定度）为（556．0±17．0）、（883．0±28．0）雠r／L时，测定值为（558．3±3．5）、（884．8±4．7）¨以，相对偏差分别为O．4％和0．2％，测定结果在不确定度范围内。结论经验证。新修订的砷铈催化分光光度方法不仅能扩展尿碘检测范围，保证尿碘测定的精密度和准确度．由于能减少实验中砷的使用量．减轻对环境污染．适合推广应用。

Objective To verify the feasibility and application value of an improved method for determination of urinary iodine by As3＋- Ce4＋ catalytic spectrophotometry. Methods Adults urine samples were co].lected, iodine calibration curves of 0 - 300 p,g/L and 300 - 1200 p^g,,＇L were prepared, and urinary iodine was determined by the improved As3＋ - Ce4＋ catalytic spectrophotometr/e method. Lyophilized human urinary iodine ingredient standards were used to validate linearity and range, limit of detection, precision and accuracy of this improved detection method. Results The linear range of the calibration curve was 0 - 300 μg/L, the detection limit was 1,8 μg/L, and the range of correlation coefficient was - 0.9995 - - 0.9997. When measuring urinary iodine at 40 - 80, 100 - 149, 200 - 280 p,g/L, the relative standard deviations were 1.5%, 0.8% and 0.5%. When measuring urinary iodine at 40 - 80, 100 - 149, 150 - 180 μg/L, the average recoveries were 97.8%, 99.8% and 96.6%. Two given values of urinary iodine of national standard samples were （73.0 ± 9.0） and （206.0 ± 10.0）μg/L, and the results determined by this method were （75.5 =1： 0.9） and （207.5 ± 1.9）μg/L, and the relative deviation was 3.4% and 0.7%, respectively, the results determined were all within the given value range. The linear range of the calibration curve was 300 - 1200 μ/L, the detection limit was 305.2 μg/L, the range of the correlation coefficient was - 0.9996 - - 0.9999. When measuring urinary iodine at 300 - 400, 500 - 600 and 1000 - 1200 μg/L, the relative standard deviations were 0.6%, 1.0% and 0.7%. When measuring urinary iodine at 300 - 499, 500 - 599 and 600 - 700 μg/L, the average recoveries were 99.7%, 99.2% and 100.4%. Two givenvalues of urinary iodine of national standard sarnples were （558.3 ± 3.5） and （884.8 ± 4.7）μg/L, the results determined by this method were （556.0 ± 17.0） and （883.0 ± 28.0）txg/L, and the relative deviation was 0.4% and 0.2%, respectively, the results were all within the given value range. Conclusions This method extends the detection range of iodine concentration, and improves precision and accuracy. This method greatly reduces the amount of arsenic used therefore reduces environmental pollution, which is suitable for promotion.