丝素膜修饰电极pH电荷选择效应的研究  

pH-Responsive Charge Selective Recognition Based on Silk Fibroin Membrane Modified Graphite Electrodes

作　　者：彭图治[1] 胡晓波[1] 杨丽菊[1] 陈建勇[2] 

机构地区：[1]浙江大学西溪校区化学系,杭州310028 [2]浙江工程学院纤维工程分院,杭州310033

出　　处：《化学学报》2001年第2期247-252,共6页Acta Chimica Sinica

基　　金：中国科学院长春应用化学研究所电分析化学开放实验室;浙江省分析测试基金资助项目

摘　　要：研究了丝素膜的带电特性 ,其等电点在pH 4.5附近 ,利用丝素膜在等电点前后的两性荷电特性和电荷之间的静电作用 ,研制了丝素膜修饰石墨电极 .多巴胺在膜中的表观扩散系数为 2 .65× 10 -7cm2 /s ,其电极反应异相电子转移速率常数为 8.9× 10 -6 cm/s .电极用于神经递质类化合物体系的测定中 。The silk fibroin protein membrane is an amphoteric ion - exchange membrane composed of both weak acidic and weak basic groups. Its isoelectric point is pH 4.5 and the charge thereof is dependent on pH of the solution. This characteristics of the membrane was exploited in a chemical modified electrode in this paper. Silk fibroin protein membrane was modified on a graphite electrode, the pH - responsive function of the modified electrode was investigated. The apparent diffusion coefficient of DA in the fibroin membrane was 2.65 x 10(-7) cm(2)/s. The rate constant of the heterogeneous electron transfer was calculated to be 8.9 x 10(-6) cm/s by computer fitting. When the modified electrode was applied to detect neurotransmitters, some metabolites and ascorbic acid did not interfere with the measurement.

关 键 词：丝素膜 修饰电极 PH电荷选择效应 石墨电极 神经递质 多巴胺 电化学 测定 

分 类 号：O657.1[理学—分析化学] Q42[理学—化学]