Direct Electrochemistry Transfer and Electrocatalysis of Hemoglobin Immobilized in Porous Mn2O3

Novel porous Mn2O3 with good crystallinity was synthesized via hard-template method. Hb-Mn2O3 nanocomposite was prepared and used for biosensor construction. The Hb-Mn2O3-Nafion modified electrode shows fast direct electron transfer and displays good electrocatalytic response to the reduction of H2O2. The response time is less than 5 s, the sensitivity is as high as 493 μA·L·mmol-1·cm-2 in a linear range of 1-100 μmol/L, and the detection limit is 0.16 μmol/L. This modified electrode also shows good stability and reproducibility. This indicates that the porous Mn2O3 provides a good matrix for enzyme immobilization and biosensor construction.