Direct electron transfer of immobilized superoxide dismutase (Cu, Zn-SOD) onto silicon carbide (SiC) nanoparticles displays a pair of well defined and nearly reversible redox peaks with formal potential (E8’) of 0.03 V in pH 7.4. The heterogeneous electron transfer rate constant (ks) and surface coverage (G) of immobilized SOD are 11.00.4 s1 and 1.421011 mol cm2. Biosensor shows fast amperometric response (3s) with sensitivity and detection limit of 1.416 nA mM1, 1.66 mM, and 1.375 nA mM1, 2.1 mM for cathodically or anodically detection of superoxide, respectively. This biosensor also exhibits good stability, reproducibility and long life-time.
