Fig. 5: Effect of spike protein coated gold electrode on the biosensor sensitivity.
From: Label-free impedimetric immunosensor for point-of-care detection of COVID-19 antibodies
a Impedance magnitudes recorded after different sequential stages of surface functionalization with APTES, MUA, SA, and S-protein immobilization. b As depicted schematically in Figure 1, Bode plot of the experimental EIS spectra before (black dashed line) and after (redline) incubation with the serum sample. c Magnified EIS spectra plotted to show the impedance change. d Plot of the detection signal ΔZRel % (ΔZRel % = ΔZ/Zbgr × 100). All EIS measurements were performed in 0.001× PBS.
