摘要
基于血红蛋白-硅酸铝(Hb-AlSiO4)凝胶膜修饰电极,制备了一种非媒介体型的过氧化氢生物传感器,血红蛋白在修饰电极上能给出直接电化学。用傅立叶变换红外光谱(FTIR)、扫描电子显微镜(SEM)、X-光电子能谱(XPS)和电化学技术对包埋Hb和未包埋Hb的AlSiO4凝胶进行了表征。凝胶层表面化学洁净,具有凝胶固有的多孔结构,形态均一而且粒径分布均匀。得到的AlSiO4凝胶修饰电极能有效地保持酶的活性,在长时间的保存过程中能维持好的稳定性。同时,对于过氧化氢的电化学还原表现出良好的催化活性,测定了米氏常数Km,该传感器在1×10-6~4×10-4mol/L的过氧化氢浓度范围内有良好的线性关系,检测限是5×10-7mol/L。该装置具有灵敏、稳定、易于制备的优点。
An unmediated hydrogen peroxide sensor is designed by employing a hemoglobin- AlSiO4 sol-gel film modified electrode. Hemoglobin exhibits direct (unmediated) electrochemistry at the modified electrode. Both Hb and Hb entrapped AlSiO4 sol-gel films were characterized in details by scanning electron microscopy, Fourier transformation infrared spectroscopy, X-ray photoelectron spectroscopy and electrochemical techniques. The sol-gel films are uniform porous and show a very low mass transport barrier and a regular dense distribution of Hb. AlSiO4 sol-gel matrix retains the native structure and activity of entrapped Hb and prevents the enzyme from leaking out of the film. The protein also shows elegant catalytic activity towards the electrochemical reduction of hydrogen peroxide. Consequently. a prototype hydrogen peroxide sensor is prepared. Under optimum conditions, this sensor provides a linear response over the hydrogen peroxide concentrations in the range of 1 × 10^-6-4 × 10^-4mol/L. The detection limit is 5 × 10^-7Tmol/L. This configuration is shown to be sensitive, stable and easy to be fabricated.
出处
《传感器世界》
2006年第1期15-19,29,共6页
Sensor World
基金
中国博士后基金资助课题(No.2003033483)