Fig. 6. The calibration curve of the immunosensor (the embedded figure is the i–t curve response of the sensor to different concentrations of CRP, (a) blank; (b) 0.01 ng mL⁻¹; (c) 1 ng mL⁻¹; (d) 10 ng mL⁻¹; (e) 40 ng mL⁻¹; (f) 60 ng mL⁻¹; (g) 80 ng mL⁻¹; (h) 100 ng mL⁻¹).