摘要
将半胱氨酸铜（CuCysh）络合物共价键合到自组装在Au电极表面的硫代乙醇酸（TAA）单分子层上,获得了衍生化自组装CuCysh-TAA单分子膜传感器.采用扫描电镜（SEM）,X射线光电子能谱（XPS）对电极表面进行了表征.固定在电极表面的CuCysh在（pH 5.5）0.2 mol/L NaAc-HAc中对H2O2的还原显示出较好的电催化响应, 测定线性范围在5.0×10^-7～3.0×10^-4 mol/L之间, H2O2在12 s内达到95%的稳态电流, 检出限为1.6×10^-7 mol/L （S/N=3）.在较大的H2O2浓度范围内, 该传感器表现出Michaelis-Menten行为.表观Michaelis-Menten常数为0.34 mmol/L.较小的值表明固定在金电极表面的半胱氨酸铜络合物对H2O2具有较高的亲和性.同时,该电极具有较好的稳定性和重现性.
A monolayer sensor was formed based on the covalent binding of cysteamine Cu complex（CuCysh） on a thioethyl alcohol acid（TAA） modified gold electrode by using the self-assembly technique and chemical derivative method. The surface of electrode was characterized by scanning electron microscopy （SEM） and X-ray photoelectron spectormetry （XPS） . The biosensor displayed excellent electrocatalytical response to the reduction of H2O2 in 0.2 mol/L NaAc-HAc （ pH 5.5） buffer solution. The steady-state current reached 95% in less than 12 s. The sensors responded to H2O2 in the concentration range of 5.0 × 10^-7 - 3.0 × 10^-4 mol/L. The detection limit was 1.6 × 10^ -7 mol/L （ S/N= 3 ）. The catalytic response shows a Michaelis- Menten behaviour at larger H2O2 concentrations. The KM^app values for the sensors was found to be 0.34 mmol/L. The low KM^app values demonstrate that cysteine Cu complex on the electrode exhibites a high affinity to H2O2. Meanwhile, this biosensor also shows good stability and reproducibility for long-term use.
出处
《分析化学》
SCIE
EI
CAS
CSCD
北大核心
2006年第4期479-483,共5页
Chinese Journal of Analytical Chemistry
基金
国家自然科学基金(No.20075023)
中国博士后基金(No.200333483)资助项目
关键词
自组装
电催化还原
半胱氨酸铜
硫代乙醇酸
化学修饰电极
Self-assembly, electrical catalyze reduction, cysteamine copper complex, thioethyl alcohol acid,chemically modified electrode
