摘要
制备了聚硫堇(PTh)-磁性核/壳纳米粒子CoFe2O4/SiO2修饰电极。研究了神经递质多巴胺(DA)在该修饰电极上的电化学行为。实验表明,PTh-CoFe2O4/SiO2复合膜修饰电极对DA的电催化作用优于PTh修饰电极。在pH7.5的PBS中,DA在该修饰电极上的CV曲线于-0.16V和-0.22V处出现一对灵敏的氧化还原峰,峰电流显著增加。差分脉冲伏安法(DPV)氧化峰电流ipa与DA浓度在1.2×10-7~3.6×10-5mol/L范围内呈良好的线性关系,线性回归方程ipa(μA)=5.307c(μmol/L)+0.7891,r=0.9923,检出限为6.0×10-8mol/L(S/N=3)。常见物质对DA的检测无干扰,DA注射液样品检测结果与中国药典2010版(二部)规定方法一致。
A polythionine-CoFe2O4/SiO2 composite nanoparticles ( PTh- CoFe2O4/SiO2) modified electrode was prepared, and the electrochemical behavior of dopamine (DA) on the PTh-CoFe2O4/SiO2 modified electrode has been studied.According to the experiment, the PTh- CoFe2O4/SiO2modified electrode has stronger electrocatalytic effect on the oxidation of DA than polypyrrole (PTh) modified electrode does. In pH7.5 PBS, one sensitive pair of redox peaks with Eps=-0.16 V, Epc=-0.22 V(vs. SCE) is obtained on the PTh- CoFe2O4/SiO2 modified electrode. The peak current was markedly increased. The oxidation peak current (ips) increased linearly with the concentrations of DA in the range of 1.2× 10^-7-3.6× 10^-5 mol/L. The linear regression equation is ips(μA) =5.307 c(μmol/L) +0.789 1 with the correlation coefficient of 0.992 3, and the detection limit of 6.0 × 10^-8 mol/L. Normal substances didn't affect the determination of DA. Satisfactory results are achieved when detecting DA in injections.
出处
《化学传感器》
CAS
2012年第2期64-68,共5页
Chemical Sensors
基金
贵州省国际科技合作计划(黔科合外G字[2011]7016号)