硒代蛋氨酸与铜离子的相互作用.pdf

物理化学学报( Wuli Huaxue Xuebao
ecemocr
Acta Phye.-Chin.Sin,2010,26(12):3225-3229
3225
Article
www.whxb.pku.edu.cn
硒代蛋氨酸与铜离子的相互作用
王锐
燕
梁志红2刘莺1黄莉莉郑文杰
(暨南大学化学系,广州510632;2暨南大学分析測试中心,广州510632
摘要:采用循环伏安法和库仓法研究了研代蛋氨酸( Semet)与铜离子的相互作用.当 Semet不存在时,铜离
子在-132和71mV有一对氧化还原峰(峰VV).当铜离子与 Semet共存时,配合物在14,128,271,-194mV
有4个峰(峰,,,M)扫描电位从600mV到-600mvV时,Cu(I)-( Semet)2配合物在14mV时被还原为
Cu() Semet配合物;Cu()- Semet配合物在-194mvV被还原为Cu(O)和 Semet.由-600mV回扫时,还原产物
被逐次氧化为Cu() Semet配合物(128mV)和Cu(I)-( Semet)a配合物(271mV).同时发现Cu()- Semet配合物
在电位-100mV至200mV间是稳定的,Cu(①)的氧化还原过程被观察到、此外,采用毛细管电泳法测得二元
Cu-semet配合物的稳定常数(K和K)分別为2.24x107和2.24x10°,最后,推测Cu- Semet配合物的结构为:在
pH3.9时,铜离子通过Cu-Se和 Cu-oco键与 Semet发生配位作用;在生理条件时,铜离子通过Cu-N和
Cu-OCO键与 Semet发生配位作用
关键词:铜离子;硒代蛋氨酸;电化学特性;配位结构;毛细管电泳
中图分类号:O641
Interaction between Selenomethionine and Copper lons
WANG Rui BAL Yan LIANG Zhi-hong LIU Ying
HUANG Li-li ZHENG Wen-jie
Department ofchemistry, Jinan University, Guangzhou 510032, P R. China;
' Experiment and Technology Center Jinan University, Guangzhou 510632, P R China
Abstract: The binary u-selenomethionine(Semet)complex was investigated using voltammetry and
chronocoulometry. A pair of peaks(V, V were observed at-132 and 71 mv in the Cu(NO3)2 solution
When Semet and Cu(NO) coexisted, four peaks (L, Il, Ill, and V)were observed at 14, 128, 271
and-194 mv, respectively. From the 60 to -600 mv potential scan, we observed that the Cu()-(Semet)2
complex was reduced to Cu() Se Met complex at 14 mv and then the Cu()Semet complex was reduced
to Cu(0
Semet at-194 mv. After reaching-600 mv the potential was reversed and the reduced
product was oxidized to the Cu()Semet complex at 128 mv and Cu(-(Semet) complex at 271 mv. The
Cu(D)emet complex was stable from about-100 to 200 mv and a redox process was observed for Cu(
The stability constants of the binary Cu-semet complex, 2. 24x 10()and 2.24x10'(,), were determined
by capillary electrophoresis. We proposed the structures of Cu-semet complexes: Copper coordinated
with Semet by the formation of Cu-se and CU-OCO bonds at PH 3.9 or by the formation of CU-N and
Cu-oco bonds under physiological conditions
Key Words: Copper ion; Selenomethionine Electrochemical characteristic; Coordination structure
Capillary electrophoresis
Rcceived: July 2, 2010; Revised: October 8, 2010; Published on Web: November 2, 2010
Correspondingauthors.BALYan,Email:taiyan(@jnu.edu.cn.ZHENGWen-jie,Email:tzhengwj@inu.edu.cn;Tel:+86-20-85220223
The project was supported by the National Natural Science Foundation of China(20771044 and Natural Science Foundation of Guangdong Province
China(825106320100000
国家自然科学基金(207104)和广东省自然科学基金(82510632010000资助项目
C) Editorial office of Acta Physico-chimica Sinica