Graphene Oxide: Intrinsic Peroxidase Catalytic Activity and Its Application to Glucose Detection By Yujun Song, Konggang Qu, Chao Zhao, Jinsong Ren, and Xiaogang Qu*
Introduction 1.GN的研究现状使其在医药诊断和生物技术方面的应用成为可能； 2.本文提出GO-COOH有类似过氧化物酶的作用，并简介研究成果。 1.提出过氧化物酶作为H2O2和葡萄糖诊断试剂的应用还有广阔的发展空间； 2.简介葡萄糖传感器的研究现状（特别强调了下HRP），并将本文中的GO-COOH和HRP进行了简单的对比。 Simple Cheap highly sensitive highly selective
Experimental Expandable graphite flake + NaCl ground 10min H2O2+GO+TMB H2O UV-vis filtration Glucose+GOx+GO+TMB Hummer’s method AFM FTIR EDX GO-COOH   X. M. Sun, Z. Liu, K. Welsher, J. T. Robinson, A. Goodwin, S. Zaric, H. Dai, Nano Res. 2008, 1, 203.
Results Ping-pong mechanism
Results [LUMO] Electron transfer mechanism
Conclusion • 1 GO-COOH possesses intrinsic peroxidase-like activity and its catalysis is strongly dependent on pH, temperature, and H2O2 concentration, similar to HRP. • 2 In the presence of H2O2 and peroxidase substrate TMB, GO-COOH can produce a blue color reaction. Kinetic analysis indicates that the catalysis follows a ping-pong mechanism, and GO-COOH has even higher catalytic activity to TMB than HRP. • 3 GO-COOH, as a mimic peroxidase, shows several advantages over natural enzymes, such as ease of preparation, low-cost, and stability. • 4 Compared to HRP and Fe3O4 nanoparticles, GO-COOH possesses high surface-to-volume ratios as well as high afﬁnity to organic substrates through π-π and hydrophobic interactions. • 5 We design and develop a simple, cheap, and highly selective and sensitive colorimetric assay to detect glucose in buffer solution or diluted blood and fruit juice samples. Our work will facilitate the utilization of GO-COOH intrinsic peroxidase activity in medical diagnostics and biotechnology.