摘要
制备了氮掺杂改性的碳纳米管,并用循环伏安法(CV)测定了多巴胺(DA)和抗坏血酸(AA)在不同氮含量的碳纳米管修饰电极上的电化学行为.结果表明,氮掺杂碳纳米管修饰电极对AA和DA有不同的电催化行为,其中高氮含量修饰电极对AA的催化作用强,而低氮含量修饰电极对DA的催化作用强.微分脉冲伏安法(DPV)的结果显示,DA的氧化峰电流与其浓度在5.0×10-6～2.0×10-4mol/L范围内呈良好的线性关系,检出限达1.64×10-6mol/L(S/N=3);AA氧化峰电流与其浓度在3.0×10-5～1.0×10-2mol/L范围内呈良好的线性关系,检出限达3.26×10-6mol/L(S/N=3).该修饰电极在AA大量存在(AA浓度为DA浓度两万倍)时可选择性地实现多巴胺的测定而不造成干扰.
The nitrogen-doped carbon nanotube （CNx nanotube） modified glassy carbon electrodes were prepared for the study of electrochemical behavior of dopamine （DA） and ascorbic acid （AA）. The effects of the content of nitrogen in the framework of CNx nanotubes on the electrochemical behavior of DA and AA at the modified glassy carbon electrodes were investigated in acidic and neutral buffer solutions. The results of cyclic voltammetry indicated that the CNx nanotube modified electrodes with a high content of nitrogen exhibited higher electrocatalytic activities for the AA, the modified electrodes with a low content of nitro- gen, however, showed the favorable electrocatalytic activity for DA. Additionally, the modified electrodes showed a linear response to DA in the concentration range of 5.0×10^-6～2.0×10^-4 mol/L and AA in the concentration range of 3.0×10^-5～2.0×10^-2 mol/L. The detection limit （S/N=3） is 1.64×10^-6mol/L for DA and 3.26× 10^-6 mol/L for AA, respectively. Such different catalytic behavior for DA and AA allowed the determination of DA in the presence of extremely excess AA （up to 20000 fold）.
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
2007年第21期2405-2410,共6页
Acta Chimica Sinica
基金
上海市教委重点基金(No.06ZZ95)资助项目.
关键词
氮掺杂碳纳米管
修饰电极
多巴胺
抗坏血酸
nitrogen-doped carbon nanotube
modified electrode
dopamine
ascorbic acid
