1-(4-安替比林)-3-(4-硝苯基)-三氮烯与镉(Ⅱ)的显色反应研究及其应用

A Study on the Colour Reaction of Cadmium(Ⅱ) With 1-(4-Antipyrinyl)-3-(4-nitrobenzene)-triazene and Its Application

本文研究了题示试剂的一些性质及其与镉的显色反应。在TritonX-100存在下,pH为11.8～12.8时,镉(Ⅱ)与试剂生成黄色的1∶2型络合物,最大吸收位于454nm,而在536nm处,试剂与络合物吸收的差值最大。以454nm为参比波长,536nm为测量波长时,ε=2.32×10~5L·mol^(-1)·cm^(-1),线性范围。0～10μg/25ml。以双波长法成功地测定了人发中的镉含量,加入回收率为99％～102%,方法的相对标准偏差为0.87％。

The dissociation constant of 1-(4-antipyrinyl)-3-(4-nitrobenzene)-triazene(APNBT) is determined by speetrophotometry in the presence of Triton X-100. At pH 11.8 to 12.8, Cd(Ⅱ) reacts with APNBT to from a yellow complex with a ratio 1:2, which has an absorption maximum at 454 nm and has a maximum difference of absorbanee between reagent and complex at 536 nm, At 454 and 536 nm, the apparent molar absorptivities and the range of obeyed Beer's law are ε=9.5 6×10~4 L·mol^(-1)·cm^(-1), 0～10μg Cd/25m1 and ε=1.37×10s L·mol^(-1)·cm^(-1), O～171μgCd/25ml, respectively. For dual-wavelength speetrophotometry with reference wavelength of 454nm and determination wavelength of 536nm, the molar absorptivity is 2.32×10~5 L·mol^(-1)·cm^(-1), Beer's law is obeyed in the range of 0～10μg Cd/25ml.The trace cadmium in human hair has been determined by the method. The relative standard deviation (δ=5) is less than 0.87% and the recovery for the added standard cadmium reaches 99%～102%