应用自组装技术将硝酸还原酶 (NR)构筑在硫醇自组装单分子膜上 ,研究了Au/半胱胺 /NR和Au/半胱胺 /NR/卵磷脂两种酶电极在磷酸缓冲液中的直接电化学行为
Nitrate reductase (NR) and phospholipids were immobilized on gold electrodes with 2_aminoethanethio(AET) SAMs. After Au/AET/NR and Au/AET/NR/lipid were soaked in pH 7 phosphate buffers for days,a pair of pre_reversible peak appeared at around 0.202 V and 0.149 V,respsctively, irregularly grew with soaking time in blank buffer.The cathodic peak current(i pcl )of Au/AET/NR system had linear relationship with scan rate between 0.02 and 0.5 V.s -1 ,while i pcl was proportional to V 1/2 in Au/AET/NR/lipid system.The direct electron transfer of enzyme electrodes was strongly affected by pH.Compared with Au/AET,NR exhibited a higher electrochemical activity in Au/AET/lipid system.
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