Rapid Label-Free Isolation of Circulating Tumor Cells from Patients’ Peripheral Blood Using Electrically Charged Fe₃O₄ Nanoparticles

Abstract

Isolation of circulating tumor cells (CTCs) in peripheral blood from cancer patients bears critical importance for evaluation of therapeutic efficacy. The current CTC isolation strategies are majorly relying on either protein biomarkers or dimensional features of CTCs. In this study, we present a new methodology for CTC detection and isolation based on the surface charge of cancer cells, a bioelectrical manifestation of the “Warburg effect.” Negative surface charge is a direct consequence of glycolysis of cancer cells, which can be utilized as an effective biophysical marker for CTC detection and isolation. Upon cancer cells–nanoparticle interaction via optimum incubation, serum protein-coated electrically charged nanoparticles can trap different cancer cells independent of their epithelial protein expression. In fetal bovine serum , the poly­(ethyleneimine)-functionalized Fe3O4 nanoparticles, surface-decorated with protein corona, are able to efficiently capture CTCs from blood samples of colorectal cancer patients. 2–8 CTCs has been isolated from 1 mL of blood and identified by immunostaining fluorescence in situ hybridization and immunofluorescence staining in all 25 colorectal cancer patients at varied stages, while only 0–1 CTC was detected from blood samples of 10 healthy donors. Diverse CTC subpopulations of heteroploids and biomarker expression can also be detected in this strategy. The label-free, charge-based CTC method shows promise in cancer diagnosis and prognosis paving a new path for liquid biopsy.

Cancer nanotechnology: current status and perspectives

“…Gold NPs are ideal for creating highly selective, versatile, and sensitive biosensors, capable of optical and electrical detection, surface plasmon resonance, and fluorescence resonance energy transfer [ 84 , 85 ]. Nanomaterials can enable early detection of circulating tumor cells (CTCs) from peripheral blood, as was shown using magnetic NPs functionalized with polyethyleneimine/protein corona or in a separate study, tannic acid [ 86 , 87 ]. The vast range of nanotechnology applications can drastically improve cancer therapies and diagnostics, and this review provides an overview of current clinical applications and forthcoming technologies (Fig.…”

Microfluidic Chip-Based Cancer Diagnosis and Prediction of Relapse by Detecting Circulating Tumor Cells and Circulating Cancer Stem Cells

“…Using spiked blood samples, they found that the isolation of PC-3 cells using RBC-magnetic nanoparticles was superior to the non-functionalized magnetic nanoparticle, increasing efficiency from 60.22% to 95.71%. Wu et al demonstrated the superparamagnetic positively charged nanoparticle (SPPCN)-based isolation of CTCs from the real blood samples of 25 colorectal cancer patients [38]. Due to the negative surface charge of CTCs, serum protein-coated, positively charged magnetic nanoparticles can trap different types of CTCs according to their surface protein expression.…”

Recent Development of Nanomaterials-Based Cytosensors for the Detection of Circulating Tumor Cells

“…In addition, the difference in deformability and density can also be used to isolate cancer-derived CTCs [13]. The negative surface charge of cancer cells can be utilized as an effective biophysical marker for the isolation and detection of CTCs because of the excretion of lactic anions in glycolysis pathway [14]. Apart from different biophysical properties, protein biomarkers are always over-expressed on the surface of CTCs, which can be used as the targets for the isolation and analysis of CTCs from blood cells through the specific interaction between the membrane proteins and molecular probes, including antibodies, peptides and aptamers [15].…”