Studies on the Electrochemistry of Dopamine at a Pyrocatechol Sulfonephthalein Modified Glassy Carbon Electrode  

作　　者：CAI Chen-xin and XUE Kuan-hong (Department of Chemistry, Nanjing Normal University, Nanjing 210097, P. R. China) 

出　　处：《Chemical Research in Chinese Universities》2000年第1期42-48,共7页高等学校化学研究（英文版）

基　　金：the National Natural Science Foundation of China

摘　　要：The electrochemical response of dopamine(DA) at a pyrocatechol sulfonephthalein modified glassy carbon(PS/GC) electrode is reported. The electrode can be used as a detector for the determination of dopamine with a high stability and a good sensitivity. The cyclic voltammetric results indicated that there was a couple of well-defined redox peaks for dopamine at the PS/GC electrode with E_(pa)= 220 mV, E_(pc)=95 mV and the formal potential E^(o')= 157. 5 mV(vs. SCE) at 100 mV/s in the buffer solution of pH 7. 0. The PS/GC electrode can also be used to separate the electrochemical responses of ascorbic acid and DA by 54 mV with the differential pulse voltammetry. Under the selected conditions, the oxidation peak currents are linear with DA concetration in the range of 5. 0 × 10^(-6) to 5. 0 × 10^(-4) mol/L, and the detection limit is 1. 0 ×10^(-6) mol/L at S/N=3. Normalized with concentration, the relative sensitivity of dopamine to ascorbic acid reaches ca. 30. 8: 1.The electrochemical response of dopamine(DA) at a pyrocatechol sulfonephthalein modified glassy carbon(PS/GC) electrode is reported. The electrode can be used as a detector for the determination of dopamine with a high stability and a good sensitivity. The cyclic voltammetric results indicated that there was a couple of well-defined redox peaks for dopamine at the PS/GC electrode with E_(pa)= 220 mV, E_(pc)=95 mV and the formal potential E^(o')= 157. 5 mV(vs. SCE) at 100 mV/s in the buffer solution of pH 7. 0. The PS/GC electrode can also be used to separate the electrochemical responses of ascorbic acid and DA by 54 mV with the differential pulse voltammetry. Under the selected conditions, the oxidation peak currents are linear with DA concetration in the range of 5. 0 × 10^(-6) to 5. 0 × 10^(-4) mol/L, and the detection limit is 1. 0 ×10^(-6) mol/L at S/N=3. Normalized with concentration, the relative sensitivity of dopamine to ascorbic acid reaches ca. 30. 8: 1.

关 键 词：Chemically modified electrode NEUROTRANSMITTER DOPAMINE Ascorbic acid Pyrocatechol sulfonephthalein 

分 类 号：O646[理学—物理化学]