An overview of recently reported label-free biosensors for Aβ(1–42) detection^a.

Electrode materials	Receptor system	Detection techniques	Limit of detection (pg mL−1)	Ref.
Au	Anti-Aβ(1–42)/AuNPs/MPA/Au electrode	EIS, SWV	5.2	16
SiO2	Anti-Aβ(1–16)/glutaraldehyde/PVP-CHO/3-aminopropyl triethoxysilane	Electrical impedance	—	50
Graphene/rGO SPE	Anti Aβ(1–42) antibody (H31L21)/Pyr-NHS/graphene-rGO SPE	DPV	10.8*	40
Si/SiO2	(Range of antibodies**)/poly(DMA-co-NAS-co-MAPS)/silicon microarrays	Fluorescence	73	11
Carbon ink electrode of DEP chip	Monoclonal Aβ antibody/protein G/MHDA SAM/AuNPs/carbon DEP chip	EIS	2573.02*	21
ICE-Au	Anti-Aβ antibody (MOAB-2)/EDC-NHS/MHA SAM/ICE	EIS	70, 100	51
Graphene SPE	Anti Aβ(1–42) antibody (mOC64)/pDAN/graphene SPE	DPV	1.4	This work

^a*Values were converted from pM and nM to pg mL⁻¹. **SC-D17, NT-11H3, NT-8G7, Cov-4G8 and Cov-12F4.