<p> Electronic Supplementary Material </p><p>A study on the direct electrochemistry and electrocatalysis of microperoxidase-11 immobilized</p><p> on a porous network-like gold film: Sensing of hydrogen peroxide</p><p>Qian-Li Zhang,a,b Ai-Jun Wang,a Zi-Yan-Meng,a Ya-Hui Lu,c Hong-Jun Lin,a Jiu-Ju Fenga* aCollege of Chemistry and Life Science, College of Geography and Environmental Science, Zhejiang</p><p>Normal University, Jinhua 321004, China bSchool of Chemistry and Biological Engineering, Suzhou University of Science and Technology,</p><p>Suzhou, 215009, China cSchool of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang 453007,</p><p>China</p><p>*Corresponding author: [email protected], Tel./Fax: +86 579 82282269</p><p>B 350 ) A  (</p><p> t 0 n</p><p> e r r u C -350</p><p>-700 0.0 0.5 1.0 1.5 Potential(V)</p><p>Fig. S1. The CVs of the porous network-like Au film modified electrode in 0.5 M H2SO4 solution.</p><p>Scan rate: 100 mV·s–1.</p><p>1</p><p>A h -4 A</p><p> -2 /</p><p> a t n e</p><p> r 0 r u</p><p>C 2</p><p>4</p><p>-0.8 -0.6 -0.4 -0.2 0.0 Potential / V</p><p>1.6 B ) A</p><p>μ 0.8 (</p><p> t n</p><p> e r</p><p> r 0.0 u C -0.8</p><p>28 56 84 112 -1 Scan rate ( mV s )</p><p>Fig. S2 (A): Typical CVs on the MP-11/cysteamine/Cu@Au/GCE at different scan rates (curve a-h):</p><p>10, 20, 30, 40, 50, 60, 70, and 100 mV·s–1 in 20 mM phosphate solution (pH 7.0). (B): The oxidation and reduction currents vs. scan rates.</p><p>20 h 15</p><p>A 10 </p><p>/</p><p> t 5 n a e</p><p> r r 0 u C -5</p><p>-10</p><p>-15 -0.8 -0.6 -0.4 -0.2 0.0 0.2 0.4 Potential / V</p><p>Fig. S3 Typical CVs on the MP-11/cysteamine/Cu/GCE electrode with different scan rates (curve a-</p><p>2 h): 10, 20, 30, 40, 50, 60, 70, and 100 mV·s–1 in 20 mM phosphate solution (pH 7.0).</p><p>3</p><p>6 A</p><p>3 ) A μ</p><p>( t</p><p> n 0</p><p> e r r u C -3</p><p>-6 3 4 5 6 7 8 9 pH</p><p>-0.18 B Oxidation potential Reduction potential -0.24 ) V (</p><p> l a</p><p> i -0.30 t n</p><p> e t o</p><p>P -0.36</p><p>-0.42</p><p>3.0 4.5 6.0 7.5 9.0 pH</p><p>Fig. S4 (A) The oxidation and reduction currents vs. pH. (B) The oxidation and reduction potentials vs. pH.</p><p>4</p><p>6</p><p>3 ) A</p><p>μ 0 (</p><p> t</p><p> n a e r r -3 u C</p><p>-6 f -0.8 -0.6 -0.4 -0.2 0.0 Potential (V)</p><p>Fig. S5 Typical CVs towards the catalytic reduction of H2O2 on the MP-</p><p>11/cysteamine/Cu@Au/GCE in 20 mM N2 saturated phosphate solution with different</p><p> concentrations of H2O2 (curve a-f): 0, 0.010, 0.019, 0.039, 0.058, and 0.078 mM. Scan rate: 100</p><p> mV·s–1. </p><p>45 without H2O2 with 0.039 mM H O 30 2 2 )</p><p>A 15  (</p><p> t</p><p> n e</p><p> r 0 r u C -15</p><p>-30 -0.8 -0.6 -0.4 -0.2 0.0 0.2 0.4 potential (v)</p><p>Fig. S6 Typical CVs of the catalysis of H2O2 on the MP-11/cysteamine/Cu/GCE in 20 mM N2 saturated phosphate solution (pH 7.0) in the absence and presence of 0.039 mM H2O2. Scan rate: 100 mV·s-1. </p><p>5 Table S1 Examples of heme proteins based mediator-free H2O2 biosensors.</p><p>Materials Stability Linear ranges Detection Refs.</p><p> limit</p><p>MP-11/Au film 94% (2 weeks) 10 µM ~ 14 mM 0.4 μM Our work</p><p>−4 Fe3O4@ SiO2@hemin 85% (4 weeks) 1.0 µM ~ 0.16 mM 2.2×10 [1]</p><p>HRP/AuNPs 83 % (12 weeks) 8.0 µM ~ 3.0 mM 2.0 μM [2]</p><p>Cyt c/Ag nanocorals 95% (2 weeks) 1.8 μM ~ 23 mM 1.8 μM [3]</p><p>Hb/WO3 94% (2 weeks) 3.7µM ~ 0.56 mM 1.5 μM [4]</p><p>HRP/GNPs-TNTs 90% (3 days) 5.0 µM ~1.0 mM 2.1 μM [5]</p><p>Mb/ZrO2/chitosan 90% (2 weeks) 10.0 µM ~ 1.5 mM 4.0 μM [6]</p><p>{Hb/CMK-3}n no change (30 days) 1.2 ~ 57 µM 0.6 μM [7]</p><p>Mb/CDA-[bmim]BF4 95% (2 weeks) 5.0~100 μM 2.0 μM [8]</p><p>HRP/PTBA PBCs > 90% (1 month) 1 ~ 300 μM 1 μM [9]</p><p>References</p><p>1. Feng J-J, Li Z-H, Li Y-F, Wang A-J, Zhang P-P (2012) Electrochemical determination of dioxygen</p><p> and hydrogen peroxide using Fe3O4@SiO2@hemin microparticles. Microchim. 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