Acta Phys. -Chim. Sin. ›› 1999, Vol. 15 ›› Issue (10): 900-904.doi: 10.3866/PKU.WHXB19991008

• ARTICLE • Previous Articles     Next Articles

In-situ Circular Dichroism Spectroelectrochemical Study on the Redox Process of Norepinephrine

Lv Yu-Juan, Zhu Yong-Chun, Cheng Guang-Jin, Dong Shao-Jun   

  1. Laboratory of Electroanalytical Chemistry,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022
  • Received:1998-12-18 Revised:1998-12-18 Published:1999-10-15
  • Contact: Dong Shao-Jun


The redox process of norepinephrine in pH=7.0 phosphate buffer solution at glassy carbon electrode was studied by circular dichroism spectroelectrochemistry with a long optical path thin layer cell. The spectroelectrochemical data were analyzed with the double logarithm method. According to the double logarithsmic plot results, the mechanism of electrochemical oxidation of norepinephrine is an irreversible process with a subsequent chemical reaction (EC) to form a norepinephrinechrome. Both of norepinephrinequinone and norepinephrinechrome are followed E mechanisms. Some kinetic parameters about the electrochemical process, i.e. the electron transfer coefficient and number of electron transfered, αn= 0.38, the formal potential, E 1 0' = 0.20 V, the standard heterogenous electron transfer rate constant, k 1 0=1.2×10 -4 cm•s -1 for the oxidation of norepinephrine, αn=0.37, E 2 0' =0.25 V and k 2 0 =4.4×10 -5 cm•s -1 for the reduction of norepinephrinequnone and αn=0.33, E 3 0' =-0.25V and k 3 0=1.1×10 -4 cm•s -1 for the reduction of norpinephrinechrome, were also estimated.

Key words: In-situ circular dichroic thin layer spectroelectrochmistry, Norepinphrine, Electrochmical processes