基于辣根过氧化物酶/纳米金/辣根过氧化物酶/多壁纳米碳管修饰的过氧化氢生物传感器的研究

Study on a Hydrogen Peroxide Sensor Based on Horseradish Peroxidase/Nano-Au/Horseradish Peroxidase/Multi-walled Carbon Nanotubes

以固定在玻碳电极上的多壁纳米碳管为基底吸附辣根过氧化物酶,再固定纳米金,然后再结合一层辣根过氧化物酶,利用多壁纳米碳管对辣根过氧化物酶的直接电化学催化特性及纳米金对蛋白质的强吸附能力及强的电子传导特性制备了无电子媒介体的过氧化氢生物传感器.采用循环伏安法,在无电子媒介体时,该传感器对H2O2仍能具有良好的催化活性,放大了电信号,提高了该酶传感器的灵敏度及稳定性.实验证明,该传感器在H2O2浓度为1.0×10-6～1.0×10-3mol?L-1范围内有线性响应,线性相关系数r2=0.9964.并探讨了电极的稳定性、寿命及重现性.

A novel mediator-free amperometric sensor based on horseradish peroxidase （HRP）/multi-walled carbon nanotubes （MWCNT）-coated glassy carbon （GC） disk electrode to merge HRP with nano-Au has been developed. The electrochemical behavior of a film of MWCNT on GC was observed and the experiment results demonstrate that the electrode as prepared exhibits direct electron transfer between HRP and GC electrode, and electrocatalytic action toward H2O2, which amplify the amperometric response signal, and enhance the sensitivity and stability of the sensor. The biosensor showed a specific response to H202 in the range 1.0×10^-6 to 1.0× 10^-3 mol·L^-1 by CV. Moreover, the reproducibility and stability of the biosensor were also studied.