Table 2.

Summary of representative sensors for detection of IgG and VEGF.

Sensing system	Sensing principle	Biomarker	Type of assay	Linear range	LOD	refs
Au array	fluorescence	IgG	direct	1 μM ~ 1 fM	0.3 fM	44
Au/protein	electrochemical	IgG	direct	10–104 ng/mL	3 ng/mL	45
Glass/Au	colorimetry	IgG	sandwich	1~ 5000 ng/mL	60 ng/mL	46
Magnetic NPs	Piezoelectricity	IgG	sandwich	0.6–34.9 μg/mL	0.36 μg/mL	47
Au/aptamer	Voltammetry	VEGF	direct	50~150 pM	50 pM	48
Carbon fiber microelectrode	Voltammetry	VEGF	direct	10~100 pg/mL	38 pg/mL	49
SiO2/protein	Fluorescence	VEGF	direct	0 ~50 ng/mL	1.0 ng/mL	50
Au film	SPR	VEGF	direct	20 ~ 600 ng/mL	3 ng/mL	51