Kadara Rashid O, Tothill Ibtisam E
Cranfield Biotechnology Centre, Cranfield University, Silsoe, Bedfordshire MK45 4DT, UK.
Talanta. 2005 Jun 15;66(5):1089-93. doi: 10.1016/j.talanta.2005.01.020.
As copper(II) is a common ion in a variety of analytical samples, its effect on the stripping response of lead(II) at bismuth film screen-printed carbon electrode (BFSPCE) was investigated. The study was conducted using a screen-printed three-electrode system (working, counter and reference electrodes), with the carbon-working electrode plated in situ with bismuth film. Copper present at significant concentration level in samples was found to affect the sensitivity of the electrode by reducing the constant current stripping chronopotentiometric (CCSCP) response of lead(II). Recovery of the lead stripping response at the BFSPCE in the presence of copper was obtained when 0.1mM ferricyanide was added to the test solution. The ferricyanide added circumvents the detrimental effect of copper(II) by selectively masking the copper ions by forming a complex. The analytical utility of the procedure is illustrated by the stripping chronopotentiometric determinations of lead(II) in soil extracts.
由于铜（II）是各种分析样品中的常见离子，因此研究了其对铋膜丝网印刷碳电极（BFSPCE）上铅（II）溶出响应的影响。该研究使用丝网印刷三电极系统（工作电极、对电极和参比电极）进行，其中碳工作电极原位镀有铋膜。发现样品中存在的高浓度铜会通过降低铅（II）的恒电流溶出计时电位法（CCSCP）响应来影响电极的灵敏度。当向测试溶液中加入0.1mM铁氰化物时，在有铜存在的情况下，BFSPCE上铅的溶出响应得以恢复。加入的铁氰化物通过形成络合物选择性地掩蔽铜离子，从而规避了铜（II）的有害影响。通过对土壤提取物中铅（II）的溶出计时电位法测定，说明了该方法的分析实用性。
