以巯基苯并咪唑为基质的毛细电泳法测定水中的Hg2+

摘要

水体汞污染加剧,其准确快速测定非常重要.采用高压毛细电泳方法,进行水中Hg2+测定的干扰因素实验,并利用t检验进行了测定水中Hg2+的毛细电泳法的系统误差检验和与分光光度法之间的显著性检验.结果 发现:采用10mmol/L巯基苯并咪唑+50mmol磷酸氢二钠的水溶液为流动相,K+、Na+、Mg2+、Ca2+、Li+、Zn2+、Cu2+、Fe3+、Ni2+、Pb2+对水中Hg2+的测定不干扰.进而得到测定水中Hg2+工作曲线为:y=-13025x+46.877(R2=0.9958),线性区间为:0.1-20mg/L;定性检测限为0.02mg/L;回收率为98%;相对准变偏差RSD为4.47%.经计算发现毛细电泳法测定水中Hg2+无系统误差,与分光光度法测定水中Hg2+无显著性差异.建立了测定水中Hg2+的毛细电泳法,该法干扰少、操作简单、重现性好、灵敏度较高、准确度较高而且线性较宽.%The heavy metal,Hg pollution were more and more serious.So the fast determination of Hg2+is very important.The mobile phase is confirmed through the interference determination and removal by high performance capillary electrophoresis.The significance test and the analysis of system error were done by t test between the capillary electrophoresis method spectrophotometry and in determination of Hg2+.The results show that the mobile phase was mercaptobenzimidazole (10 mmol/L) + Na2HPO4(50 mmol/L).The determination of Hg2+was not affected in presence of K+,Na+,Mg2+,Ca2+,Li+,Zn2+,Cu2+,Fe3+,Ni2+,Pb2+.The working curve of ammonium determination was y=-13025x+46.877(R2=0.9958),the linear range was 0.1-20 mg/L,the limits of detection was 0.02 mg/L,the recovery was 98%,the relative standard deviation was 4.47%.It is found that there was no significant difference between the method of spectrophotometry and the method of capillary electrophoresis.And found that there was no system error in Hg2+determination by the capillary electrophoresis method.The method was established to determine the Hg2+,which has the advantages of less interference,simple operation,reproducible,wide linearity,high sensitivity and high accuracy.