三波长分光光度法同时测定痕量镉镍  

Simultaneous determination of cadmium(Ⅱ) and nickel(Ⅱ) by triwavelength spectrophotometry

作　　者：刘永文[1] 宋金萍[2] 孟双明[1] 郭永[1] 常希俊[3] 

机构地区：[1]雁北师范学院化学系,山西大同037009 [2]大同医学专科学校基础部,山西大同037018 [3]兰州大学化学化工学院,甘肃兰州730000

出　　处：《冶金分析》2006年第6期14-16,共3页Metallurgical Analysis

基　　金：山西省自然科学基金资助项目(0505013)

摘　　要：研究了三波长分光光度法同时测定Cd2+与Ni2+的条件。结果表明:在TritonX-100表面活性剂存在下,pH 11.0的Na2B4O7-NaOH缓冲溶液中,Cd2+,Ni2+与3,3’-二磺酸基联苯胺基重氮氨基偶氮苯(DSDPDAA)形成稳定的红色络合物,络合物的表观摩尔吸光系数分别为6.83×104L.mol-1.cm-1和8.93×104L.mol-1.cm-1;25 mL溶液中Cd2+和Ni2+分别在0-15μg和0-14μg范围内符合比尔定律,据此建立了三波长分光光度法同时测定Cd2+与Ni2+的新方法。对25 mL溶液中5μg Cd2+和Ni2+,测定的相对标准偏差分别为1.6%和2.4%(n=11)。方法用于污染土壤和人发标准样品的测定,结果与认定值相吻合。The conditions of determining cadmium（Ⅱ） and nickel（Ⅱ） by triwavelength spectrophotometry have been studied.The results show that in the presence of surfactant TritonX-100 and in the medium of Na2B4O7 - NaOH buffer solution （ pH 11.0 ）, 3,3-disulphobiphenylaminodiazoaminoazobenze （DSDPDAA） reacts with cadmium（Ⅱ） and nickel（Ⅱ） to form stable red complex with the apparent molar absorptivity of 6.83 ×10^4L·mol^-1·cm^-1 and 8.93 ×10^4L·mol^-1·cm^-1, respectively. Beer＇ s law is obeyed in the range of 0 - 15μg and 0 - 14 μg in 25 mL solution for cadmium and nickel, respectively. Based on this,a novel method for the simultaneous determination of cadmium（Ⅱ） and nickel（Ⅱ） by triwavelength spectrophotometry is developed.The relative standard deviations are 1.6% and 2.4% （n = 11） for 5 μg of cadmium（Ⅱ） or nickel（Ⅱ） i The method has been applied to the determination of cadmium（Ⅱ） and nickel（Ⅱ） in soil and hair certified reference samples, and the results are found to be agreement with the certified values.

关 键 词：三波长分光光度法 3 3’-二磺酸基联苯胺基重氮氨基偶氮苯 镉 镍 

分 类 号：O657.3[理学—分析化学] O614.813[理学—化学]