Korolczuk Mieczyslaw, Moroziewicz Aleksandra, Grabarczyk Malgorzata, Paluszek Katarzyna
Faculty of Chemistry, Maria Curie-Sklodowska University, Maria Curie-Sklodowska Sq. 3, 20-031 Lublin, Poland.
Talanta. 2005 Feb 28;65(4):1003-7. doi: 10.1016/j.talanta.2004.08.033.
A sensitive method of Co(II) determination by adsorptive stripping voltammetry is presented. The method exploits the enhancement of cobalt peak current observed in the system Co(II)-nioxime-cetyltrimethylammonium bromide-piperazine-N,N'-bis(2-ethanesulfonic acid). The calibration plot for an accumulation time of 60s is linear from 5 x 10(-11) to 3 x 10(-9)molL(-1). The relative standard deviation is 3.8% for Co(II) determination at concentration 1 x 10(-9)molL(-1). The detection limit is 1.7 x 10(-11)molL(-1). The validation of the method is performed by the analyses of certified reference materials and comparing the result of Co(II) determination in river water sample by the proposed method with those obtained by ET AAS. The main advantage of this new system is the micro-trace Co(II) determination by adsorptive stripping voltammetry, as compared to those described before, a low concentration of the supporting electrolyte used, and so commercially available reagents without additional purification can be used.
提出了一种通过吸附溶出伏安法测定钴（II）的灵敏方法。该方法利用了在钴（II）-氨肟-十六烷基三甲基溴化铵-哌嗪-N，N'-双（2-乙磺酸）体系中观察到的钴峰电流增强现象。在60s的富集时间下，校准曲线在5×10⁻¹¹至3×10⁻⁹molL⁻¹范围内呈线性。对于浓度为1×10⁻⁹molL⁻¹的钴（II）测定，相对标准偏差为3.8%。检测限为1.7×10⁻¹¹molL⁻¹。通过分析有证标准物质以及将该方法测定河水样品中钴（II）的结果与电热原子吸收光谱法（ETAAS）得到的结果进行比较，对该方法进行了验证。与之前描述的方法相比，这个新体系的主要优点是通过吸附溶出伏安法进行微量钴（II）测定，使用的支持电解质浓度低，因此可以使用市售试剂而无需额外纯化。
