A Highly Efficient Nano-Cluster Artificial Peroxidase and Its Direct Electrochemistry on a Nano Complex Modified Glassy Carbon Electrode

作者：Hong Jun^*; Wang Wei; Huang Kun; Yang Wei Yun; Zhao Ying Xue; Xiao Bao Lin; Gao Yun Fei; Moosavi Movahedi Zainab; Ghourchian Hedayatollah; Moosavi Movahedi Ali Akbar

来源：Analytical Sciences, 2012, 28(7): 711-716.

A nano-cluster with highly efficient peroxide activity was constructed based on nafion (NF) and cytochrome c (Cyt c). UV-Vis spectrometry and transmission electron microscopy (TEM) methods were utilized for characterization of the nano-structured enzyme or artificial peroxidase (AP). The nano-cluster was composed of a Chain-Ball structure, with an average ball size of about 40 nm. The Michaelis-Menten (K-m) and catalytic rate (k(cat)) constants of the AP were determined to be 2.5 +/- 0.4 mu M and 0.069 +/- 0.001 s(-1), respectively, in 50 mM PBS at pH 7.0. The catalytic efficiency of the AP was evaluated to be 0.028 +/- 0.005 mu M-1 s(-1), which was 39 +/- 5% as efficient as the native horseradish peroxidase (HRP). The AP was also immobilized on a functional multi-wall carbon nanotube (MWNCTs)-gold colloid nanoparticles (AuNPs) nano-complex modified glassy carbon (GC) electrode. The cyclic voltammetry of AP on the nano complex modified GC electrode showed a pair of well-defined redox peaks with a formal potential (E degrees%26apos;) of -45 +/- 2 mV (vs. Ag/AgCl) at a scan rate of 0.05 V/s. The heterogeneous electron transfer rate constant (k(s)) was evaluated to be 0.65 s(-1). The surface concentration of electroactive AP on GC electrode (Gamma) was 7 x 10(-10) mol cm(-2). The apparent Michaelis-Menten constant (K-m(app)) was 0.23 nM.

• 出版日期2012-7
• 单位河南大学