尿铬测定方法研究

URINE-Cr ASSAY WITH DIPHENYLCARBAZIDE

作者对二苯碳酰二肼比色法测定尿铬的方法进行了系统实验,建立了适宜的分析条件,从而提供了一个适用于测定尿中微量铬的分析方法。其优点是显色稳定、灵敏、准确度和精密度好,回收范围为82.0～115.8％,平均回收率为101.1％,变异系数为2.0～8.4％。用本方法对成都市180例正常人和124例冠心病人的尿样进行分析,正常人尿铬含量均值为6.1μg/L,95％正常值范围为 1.7～11μg/L,冠心病人尿铬含量均值为4.2μg/L。两组样品的均值有显著性差异(t'=6.9,P<0.05)。

Systemic investigations of chromiumdetermination in urine with diphenylcarba-zide were carried out and suitable analyticconditions for the determination established.Urine samples were first digested withnitric acid-hydrogen peroxide and then thechromium in the sample was oxidized to thehexavalent state by permanganate in acidicmedium. After the excess oxidizing reagentwas destroyed with sodium nitrite, chromi-um (Ⅵ) combined with diphenylcarbazide,forming a stable red color. The averagerecovery was 101.1%, ranging from 82.0%to 115.8%. Coe ficients of variation were inthe range from 2.0% to 8.4%. The methodcan be conveniently apptied to the analysisof trace chromium in urine samples withsatisfactory sensitivity and recovery. The method was applied to the meas-urement of 180 normal and 124 CHD(coronaryheart disease) urine samples from Chengducity. The mean of chromium level in normalurine was 6.1μg/L and the range with 95%confidence of urine chromium was determin-ed as 1.7-11μg/L. The mean of chromiumlevel in CHD urine samples was 4.2μg/L.By statistical analysis, there was a signifi-cant difference between the means of thetwo groups (t'=6.9, P<0.05).