摘要
以玻碳电极(GCE)为工作电极,用循环伏安法(Cyclic voltammetry,CV)分别研究了槐定碱(Sophoridine,SR)和苦参碱(Matrine,MT)在十二烷基三甲基溴化铵(Dodecyltrimethylammonium,DTAB)、十四烷基三甲基溴化铵(Tetradecyltrimethylammonium,TTAB)、十六烷基三甲基溴化铵(Hexadecyltrimethylammonium,CTAB)和溴代十六烷基吡啶(Cetylpyrid bromide,CPB)阳离子胶束中的电化学行为,并对其进行比较。结果表明,在不同阳离子胶束体系中SR和MT的氧化峰电流Ip均有所降低,氧化峰电位Ep均发生正移。同时研究了pH在2.0～9.5范围及胶束存在下介质pH值及不同浓度NaCl支持电解质对SR和MT电化学行为的影响,并给出合理的解释。运用计时库仑法(Chronocoulometry,CC),计时电流法(Chronoamperometry,CA)测定了有无胶束存在时SR和MT的扩散系数D,电荷转移系数α和电极反应速率常数kf,并对其进行了比较。结果表明,在不同介质中SR和MT的动力学参数大小顺序为:H2O>DTAB>TTAB>CTAB>CPB。
The electrochemical behaviors of Sophoridine（SR） and Matrine（MT） in the presence of Dodecyltrimethylammonium （ DTAB ）, Tetradecyltrimethylammonium （TTAB）, Cetylpyrid bromide （ CPB ） and Hexadecyltrimethylammonium（CTAB） micellar solution have been studied by cyclic voltammetry（CV） at GCE. The electrochemical experimental results showed that the electrochemical oxidations of SR and MT are influenced with different cationic surfactants. The influence of solution pH on oxidation peak currents （Ip） and peak potentials （Ep） in the presence of cationic surfactants were studied in the range of pH2.0 to 9.5. It is obtained that SR and MT were oxidized with no proton participation in the electrode process in absence or presence of surfactants. Also the influences of NaCl concentration on the interaction of CTAB and SR or MT were studied, and it has given the reasonable explanations. The electrochemical kinetic parameters of SR and MT in the presence and the absence of cationic surfactants were determined by chronocoulometry（CC）and chronoamperometry（CA）. Compared with diffusion coefficient D, electron transfer coefficient α, and electrode reaction rate constant ks and showed kinetic parameters of SR and MT was H2O 〉 DTAB 〉 TTAB 〉 CTAB 〉 CPB.
出处
《化学传感器》
CAS
2008年第2期51-56,共6页
Chemical Sensors
基金
宁夏高等学校科学研究基金项目(200623)资助
关键词
槐定碱
苦参碱
阳离子胶束
电化学行为
sophoridine
matrine
cationic micelles
electrochemical behaviors
