摘要
在氨性介质中(pH=9.0),钴(Ⅱ)-丁二酮单肟烟酰腙(DMNH)-亚硝酸盐体系可产生灵敏度很高的催化波。从体系的伏安行为可知,吸附于汞电极上的是混配的配盐NH_4[Co(Ⅱ)(DMNH)·(NO_2)_2],在-1.0 V(相对SCE)处,Co(Ⅱ)被还原至Co(0),DMNH被还原成自由基,由于NO_2^-的存在,自由基可参与再生反应而形成催化波。羟氨的存在可使产生催化波的最佳pH值移至8.2.用此体系进行了生物样品中钴的测定,其检出限为1×10^(-10)mol/L。
A sensitive catalytic wave can be obtained in Co(Ⅱ)-DMNH( 1,2-dimethyl-2-nicotinic hy-drazone ethyleneoxime)-NO-2 system (pH = 9). The voltammetric behaviour of this system is studied in this paper. A compound NH4Co(DMNH)(NO2)2 was adsorbed on the surface of hanging drop mercury electrode at -0. 70 V(vs. SCE). In cathodic scanning, NO-2 could be reduced catalytically by it at - 1. 0 V and produced a catalytic wave. If hydroxyamine exists in above base solution, the catalytic wave is also obtained, but the optimum acidity is shifted from pH 9 to 8. 2. Using latter system, the content of cobalt in biological samples was determined by adsorptive stripping voltammetry. The results of analysis were satisfactory. The detection limit of cobalt is 1×10-10 mol/L.
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
1991年第3期311-314,共4页
Chemical Journal of Chinese Universities
基金
国家自然科学基金
关键词
钴
肟类试剂
亚硝酸盐
DMNH
测定
Voltammetric behaviour of cobalt, Determination of cobalt, 1, 2-Dimethyl-2-nicotinic hydrazone ethyleneoxime
