基于Hemin/多壁碳纳米管纳米复合物构建的过氧化氢生物传感器的研究

Research on Hydrogen Peroxide Biosensor Constructed by Complex of Hemin and Multi-Walled Carbon Nanotubes

利用卟啉（Heroin）具有模拟酶的功能，与多壁碳纳米管（MWCNTs）构建了一种新型的过氧化氢（H2O2）生物传感器。首先，利用Hemin与MWCNTs之间的π-π键作用，在超声分散下制备Hemin／MwcNTs纳米复合物；采用滴涂技术并在nafion的作用下将其固载在电极表面，制得该H2O2生物传感器（nafion／Hemin／MWCNTs／GCE）。采用紫外-可见分光光度法（uV—Vis）对合成的纳米复合物进行了分析；采用扫描电镜（SEM）对电极的表面形貌进行了表征；采用循环伏安法和计时电流法考察了该修饰电极的电化学行为；并对传感器的行为进行了详细的研究。在最优条件下，此修饰电极对H2O2具有明显的催化作用，电流与H。0：的浓度在6．0×10 -7 -1．8×10 -3mol／L范围内呈现良好的线性关系，检出限达2．0×10 -7mol／L。此传感器制作简单，具有较高的灵敏度和良好的稳定性及重现性。

A novel hydrogen peroxide （H2O2） biosensor was constructed using porphyrin （Hemin） with intrinsic peroxidase-like activity and multi-walled carbon nanotubes （MWCNTs）. First, by ultrasonic dispersion, Hemin/MWCNTs nanoeomposites were generated due to π-πbond interaction between Hemin and MWCNTs. Then, the composite was immobilized to electrode surface by drop coating technique in the presence of nafion, forming a hydrogen peroxide biosensor with a structure of nafion/ Hemin/MWCNTs/GCE. The composite was characterized using UV-visible spectrophotometry（UV-Vis）. The surface morphology of the electrode was characterized by scanning electron microscopy （SEM）. The electrical and chemical behaviors of the electrode were studied using cyclic voltammetry （CV） and amperometric method. The properties of sensor were investigated in detail. Under optimal conditions, the electrode had an obvious catalytic effect to H2 O2 and the linear response range for H2 O2 was from 6.0 × 10 -7 to 1.8× 10 -3 mol/L. The detection limit was 2.0× 10-7 mol/L. The sensor was made by a simple procedure and demonstrated high sensitivity, good stability and reproducibility.