Table 1.

CTC Detection Technologies

Principle	Material/Device	Characteristic	Target	Tumor Type	Sensitivity%	Specificity%	Viability%	Ref
Immunoaffinity	Immunomagnetic	Immunonanocomposites equipped with fluorescence and magnetic properties (ZnS:Mn2+ quantum dots and Fe3O4/SiO2), which achieved capture and identification of CTCs simultaneously.	EpCAM	CRC/BC	90.8	–	–	[23]
	Nanofibers	Poly ethylene oxide(PEO) was blended into nylon-6 through electrospinning to produce a fibrous mat-based CTCs detection method. High cell-substrate affinity and low leukocyte adsorption.	EpCAM	CRC	66.7–70.6	> 99	–	[24]
	bio-microchip	ZnO nanowire coated polydimethylsiloxane (PDMS) pillar microchips with a gear structure. More binding sites and rough surface.	EpCAM	CRC/BC	91.11 ± 5.53	–	96	[25]
	Immunomagnetic	Tumor-targeting molecule FA and magnetic nanoparticles (MNPs) coated red blood cells. Natural cell membrane avoided absorption by leukocytes.	FR	BC	> 90	> 75	> 90	[26]
	Nanovesicles	FA and fluorescein Cy5 coated erythrocyte-derived nanovesicles. Achieving Tumor targeting and fluorescence imaging simultaneously.	FR	CRC/BC	> 95	> 90	–	[27]
	Fluorescent probe	FA functionalized terbium-doped dendritic fibrous nanosilica fluorescence spectrometry. Fluorescence microscopy and flow cytometry were utilized to verify the uptake of the fluorescent probe with FR-positive tumor cells.	FR	CRC	85	–	> 80	[28]
	Immunomagnetic	rVAR2 protein coated micromagnetic beads. rVAR2 binding is unaffected by phenotypic plasticity.	ofCS	HCC/LC/PAAD/PC	86.0–91.9	–	–	[30]
	Immunomagnetic	rVAR2 protein coated micromagnetic beads.	ofCS	GBMLGG	54–75	–	–	[31]
	Microfluidic	Membrane protein O-glycan sialyl-Tn (STn) glycan-affinity microfluidic devices.	sTn	CRC	22	> 99.5	–	[36]
	Immunomagnetic	EpCAM incombination with EGFR and HER3 based enrichment can significantly improve the detection rate of CTCs.	EpCAM/EGFR/HER3	NSCLC	66.7	–	–	[37]
	Immuno-microbeads	Anti-EpCAM and anti-CD146 antibodies functionalized gelatin nanoparticle-coated silicon microbeads (SiO2@Gel MBs). SiO2@Gel MBs have large size and high density. The gelatin coating allows the release of captured CTCs with low damage and high efficiency.	EpCAM/CD146	BC/CRC	> 80	> 85	92.5	[38]
	Immunomagnetic	FA and anti-EpCAM antibody functionalized magnetic hyaluronan capsules.	EpCAM/FR	BC	> 88	95	–	[39]
	Microfluidic	A platform integrated of dendrimer-mediated multivalent binding, a mixture of antibodies and biomimetic cell rolling.	EPCAM/EGFR/CA9/c-Met	RCC	80	–	–	[40]
	Magnetic dynamic microbiointerface	A saccharide-sensitive biomimetic microplatform, which can mimick the dynamic properties of natural excellular matrix. Good biocompatibility, high capture efficiency, excellent cell selectivity.	mussel-inspired cancer cell-targeting peptide	BC	85	–	–	[42]
	AuNPs Electrochemical	Gold nanoparticle-based multipedal DNA walker. TCEP-mediated electrochemical amplification is used to further enhance the electrochemical signal. High sensitivity and anti-interference ability.	DNA probes	ALL	> 96.3	–	–	[43]
Biophysical Properties	Microfluidic	A spiral microchannel with inherent centrifugal force. Taking advantage of two phenomena: Dean migration and inertial focusing. Only the larger CTC undergo inertial focusing and be collected.		LC	100	10	> 98	[52]
	Microfiltration	A 3D palladium filter with an 8 mm-sized pore and a 30 mm-sized pocket. A device driven by gravity flow.		BC/GC/CRC/PAAD	> 85	–	–	[53]
	Microfiltration	A high-density microporous (HDM) chip. High sensitivity and specificity, simplicity, and low cost, enables subsequent single cell molecular characterization and analysis.		CRC	65.8	96	–	[54]
	Density gradient centrifugation	The unique separation tube and collector of AccuCyte system enable the complete separation of the buffy coat layer of white blood cells and platelets.		BC/PC/CRC	90.5	81	–	[57]
	Microfluidic	Consist of deterministic lateral displacement (DLD) isolating structure, an automatic purifying device with CD45-labeled immunomagnetic beads and a rat-tail collagen coated capturing platform.		LC	90	50	> 90	[58]
	Microfluidic	A sequential ensemble decision aliquot ranking (eDAR) chip with two sorting nodes. CTCs are detected by laser-induced fluorescence(PE-EpCAM), then the CTC-detection signals activate a solenoid and change the pressure of flow to achieve sorting at two junctions.		BC	> 90	70	–	[61]