基于固定化电子媒介体的漆酶电极的制备与应用

Preparation and Application of Laccase Electrode Based on Immobilized Mediator

采用一种新方法引入媒介体,即将媒介体2,2-连氮-双(3-乙基苯并噻唑啉-6-磺酸)(ABTS)固定在多壁碳纳米管(MWCNTs)上,将壳聚糖与漆酶共同修饰在玻碳电极表面,制备了漆酶电极。实验发现,ABTS能够被牢固地吸附在多壁碳纳米管上,且吸附了ABTS的多壁碳纳米管在水中的分散性能大为改善。由于ABTS的存在,该漆酶电极能够更加有效地催化氧气还原,使氧气的还原电位从-0.1 V升至0.6 V。研究了修饰在多壁碳纳米管上的ABTS的电化学行为,并讨论了碳纳米管修饰量、pH值及温度对漆酶电极催化性能的影响。该方法简单,制备的漆酶电极对氧气还原的催化效率高,有望应用于植入型生物燃料电池。

A novel method for fabricating laccase electrode was developed by immobilizing mediator on multi-walled carbon nanotubes（MWCNTs） with laccase using chitosan as fixative.The mediator 22-azinobis（3-ethylbenzothiazoline-6-sulfonate）（ABTS）was introduced to permit effective shuttling of electrons between laccase active site and the electrode.The electrochemical behavior of ABTS on multi-walled carbon nanotubes was investigated.The result indicated that ABTS could be strongly Absorbed onto multi-walled carbon nanotubes,and the multi-walled carbon nanotubes modified with the mediator could produce stable colloidal suspensions with water.Compared with bare electrode,laccase on the modified electrode could catalyze the reduction of oxygen at a much more positive potential of 0.6 V,which is of great importance for the fabricating of biofuel cell.The effect of several experiment parameters,including the amount of ABTS-MWCNTs solution,pH value and temperature on catalytic performance of the modified electrode were optimized.The laccase electrode with 10 μL ABTS-MWCNTs solution showed the best catalytic efficiency to oxygen at 40 ℃ in pH 6.0.The simiplicity and high catalytic efficiency of the laccase electrode made it be of great potential to apply in implanted biofuel cell.