Table 4.

Specifications and electrochemical performance of CTCs aptasensors

CTCs	Sensor Specification	Method	Sensing Strategy	Sample Matrices/ Interferents	Detection Range	Limit of Detection (LOD)	Ref.
MEAR cancer cells	dual-apt. TLS1c, TLS11/amide bond/GCE	DPV [Fe(CN)6]3−/4−	label-free	blood cells	1−14 MEAR cells	single MEAR cell/109 whole blood cells	[110]
CTCs	EpCAM apt./MCH/Au electrode	EIS [Fe(CN)6]3−/4−	label-free	real blood sample	30–1 × 106 cells L−1	10 cells mL−1	[111]
acute leukemia CCRF-CEM	Apt./array nanochannel–ionchannel hybrid	LSV	label-free	k562 cells, Ramos cells	1 × 102–2 × 106 cells mL−1	100 cells mL−1	[112]
MCF-7 circulating tumor cells	MUC-1 apt./rGO/AuNPs composites	DPV CuO NPs, H2O2	label-free	serum sample	50–7 × 103 cells mL−1	27 cells mL−1	[64]
Ramos, CCRF-CEM cells	Apt.–AuNPs Array/Magnetic Gr Nanosheets	SWASV multiplexed detection	label-free	human whole blood	5–500 cells mL−1	Ramos 4 cells mL−1 CCRF-CEM cells 3 cells mL−1	[62]
CTCs K562 cell	AuNPs/Au electrode, MB–apt.	Alternating current voltammetry (ACV) MB	signal-off	U937, Jurkat cells	1 × 102–1 × 106 cells mL−1	23 cells mL−1	[114]
Breast cancer cell MCF-7	Fe3O4 magnetic nanospheres (MNs)/EpCAM antibody	SWV molybdophosphate (PMo12O40) redox label	antibody–aptamer sandwich type	whole blood samples	3–10,000 cell mL−1	1 cell mL−1	[115]
MCF-7 cells	Membrane protein MUC1-targeting apt.	dual signal, (Ce@IrNRs) enzyme-free DNA walker	enzyme-free DNA walker	whole blood samples	2–2 × 106 cells mL−1	1 cell mL−1	[116]
CTCs MCF-7	Apt. magnetic beads MBs	DPV ferroceneboronic acid (FcBA)	label-free strategy	blood sample	50−2 × 104 cells	50 cells	[117]