钴(Ⅱ)与3-噻唑偶氮-5-氨基苯酚生成的络合物的极谱吸附波  

Polarographic Adsorptive Wave of Coordination Complex Formed Between Cobalt(Ⅱ) and 3-Thiazolylazo-5-aminophenol

作　　者：杜芳艳[1] 邓保炜[1] 张亚[1] 

机构地区：[1]榆林学院化学系,榆林719000

出　　处：《理化检验（化学分册）》2008年第3期255-257,共3页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

摘　　要：在pH8．0的硼砂-盐酸缓冲溶液中，钴（Ⅱ）与3-噻唑偶氮-5-氨基苯酚（3-TAP）生成的络合物有一灵敏的极谱吸附波，其峰电位在-0．74V左右（vs．SCE），峰电流的二阶导数（I″p）与钴（Ⅱ）的质量浓度在0．001-1．4mg·L^-1范围内呈线性关系，经多种电化学方法证明该波为络合吸附波，其电极过程为不可逆过程，电子转移数为2。此外，还试验了多种离子对峰电流I″p的影响，所拟方法用于3种维生素B12注射液样品中钴的测定，所得结果与标示值相符，测定结果的相对标准偏差（n=6）均小于2．5％。按标准加入法测得方法的回收率在92．0％～107．0％之间。A sensitive polarographic adsorptive wave of the coordination complex formed between Co（ Ⅱ ） and 3-thiazolylazo-5-aminophenol （3-TAP） in a borate buffer of pH 8. 0 was observed at the potential of-0. 74 V （vs. SCE）. Linear relationship was kept between the 2nd derivative of peak current （I″p） and concentration of cobalt（ Ⅱ ） in the range within 1.4 mg·L^-1. It was proved that the polarographic wave was an adsorptive wave, and that the electrode reaction was an irreversible process, involving transfer of 2 electrons. Tests for interfering effects of coexising ions to the values of I″p were also studied. The proposed method has been applied to the determination of cobalt in 3 samples of vitamin B injections giving results checked quite Well with the labelled values, and values of RSD＇s （n=6） found were less than 2.5%. Values of recovery found by standard addition method were in the range from 92.0% to 107.0%.

关 键 词：络合物的极谱吸附波 钴 3-噻唑偶氮-5-氨基苯酚 维生素B12注射液 

分 类 号：O614.242[理学—无机化学] O614.812[理学—化学]