利用1,6-己二硫醇作为联结剂将纳米金颗粒修饰到金盘电极上,再以L-半胱氨酸为修饰剂使纳米金颗粒功能化并进一步与漆酶充分作用,制备了固定漆酶的纳米金颗粒修饰金盘电极并以循环伏安法测试了其对氧还原的催化性能.实验结果表明:O2在该电极上还原电位约为-0.26 V(vs SCE),氧还原峰电流为3.0 uA(25℃),较文献[7]报导的固酶聚异丙基丙烯酰胺(PNIPAM)水凝胶修饰ITO电极的氧还原催化性能要优.(氧气还原电位:-0.26 V,vs NHE,峰电流:0.47 uA)进一步研究表明:本文制备的修饰电极稳定性好,适于长期使用而且热稳定性优于文献[7]报道的固酶聚异丙基丙烯酰胺水凝胶修饰ITO电极:50 ℃时在本文制备的纳米金修饰电极上氧还原峰电流仍保持为25℃时修饰电极上氧还原峰电流的40%左右.%Gold disk electrode was modified with nanogold particle using 1,6-hexanedithiol (HET) as linker and nanogold particle modified with L-cystein to be functionalized was reacted with laccase enough to immobilize enzyme tightly.After doing so,gold disk electrode modified with nanogold particle which covalently coupled with laccase has been achieved. The catalytic function towards oxygen reduction reaction (ORR) of prepared electrode was evaluated with cyclic voltammograms (CV). The results obtained from experiments which indicated dioxygen reduction reaction on prepared electrode occurred at about -0.14 V ( vs SCE), much better than that of literature [ 7 ] reported (-0.26 V vs NHE) ITO electrode modified with poly(N-isopropylacrylamide) (PNIPAM) hydrogel;peak current of ORR on prepared electrode was 3.0 μA or so,about 6.5 times of that of literature[ 7 ] reported ITO electrode modified by PNIPAM with laccase.Further investigation showed gold disk electrode modified by nanogold particle with immobilized laccase through covalent coupling had excellent stability for long-term use and had better thermal stability than literature[ 7 ] reported ITO electrode modified with PNIPAM hydrogel:prepared electrode can retain 40％ of peak current corresponding to oxygen reducfion at 25 ℃ when system temperature was kept at 50 ℃.
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