Fig. 5.

a Calibration curve of 0.5 mM concentration of H₂O₂ versus catalytic peak current and error bar with trend line equation and linear range (0.00025–5.0 mM) with a correlation coefficient of 0.9986; b amperometric response curves of Hb/DNA/NPGF addition of 30 nM, 62.5 nM, 125 nM, 250 nM and 500 nM H₂O₂ solution