Double-Tetrahedral DNA Probe Functionalized Ag Nanorod Biointerface for Effective Capture, Highly Sensitive Detection, and Nondestructive Release of Circulating Tumor Cells

Abstract

Circulating tumor cells (CTCs) are indicative of tumorigenesis, metastasis, and recurrence; however, it is still a great challenge to efficiently analyze the extremely rare CTCs in peripheral blood. Herein, a novel nanobiointerface integrating high affinities of arrayed silver nanorods (Ag NRs) and doubletetrahedral DNA (DTDN) probes by a clever strategy is proposed for the efficient capture, highly sensitive detection, and nondestructive release of CTCs. Under the optimal conditions, the DTDN-probe-functionalized Ag NRs nanobiointerface can capture 90.2% of SGC-7901 cells in PBS, and the capture efficiency is 2.8 times and 50 times those of a DTDN-probe-functionalized Ag film and unfunctionalized Ag NRs, respectively, benefiting from the nanorough interface of the Ag NRs array and multivalent recognition of the DTDN probe. In addition, 93.4% of cells was released via Zn 2+ -assisted DNAzyme cleavage, and the viability of the postreleased CTCs is about 98.0%. The potential practicality of the nanobiointerface for testing CTCs in blood was further characterized by spiking SGC-7901 cells in leukocytes collected from human blood, and the results show that 83.8% capture efficiency, 91.2% release efficiency, and single-cell detection limit were achieved, which indicates that the nanobiointerface has great potential in clinical applications for reliable CTC analyses.

Recent progress of nanostructure-based enrichment of circulating tumor cells and downstream analysis

“…Song et al fabricated silver nanorod arrays by oblique deposition and modified double-tetrahedral DNA (DTDN) probes on their surfaces for the efficient capture, highly sensitive detection and lossless release of CTCs. 100 Under the best conditions, the capture efficiency of the biological interface is 90.2%. A total of 93.4% of the cells are released by Zn 2+ -assisted DNAzyme cutting, and the survival rate of the released CTCs is about 98.0%.…”

Recent advances of liquid biopsy: Interdisciplinary strategies toward clinical decision‐making

“…Similarly, Wang and colleagues utilized DNA probes for capture and nondestructive release of CTCs. 98 After capturing 90.2% of SGC-7901 cells in PBS, 93.4% of cells were released via Zn 2þ -assisted DNAzyme cleavage, with the viability of post-released CTCs reaching approximately 98.0%. These specialized aptamers, specifically targeting the designed site, offer a unique perspective on efficient CTC isolation and lowdamage release, by simultaneously constructing the structure and composition of the aptamer.…”

“…By functionalizing double-tetrahedral DNA probes on nanorough Ag nano-biointerfaces, the synergetic effects of molecules and topographies improved the capture efficiency to 90.2% for SGC-7901 cells in PBS. 98 Pei et al utilized dual aptamers targeting EpCAM and N-cadherin proteins to enhance the capture sensitivity of both epithelial and mesenchymal CTCs, 89 achieving capture efficiencies of 91% for A2780 cells (high N-cadherin and low EpCAM) and 89% for OVCAR-3 cells (low N-cadherin and high EpCAM).…”

“…developed a microfluidic chip modified with three‐dimensional DNA structures (TDNs) as frameworks, 97 enhancing capture efficiency to around 87% due to the highly precise dimensions and rigid framework of TDNs. By functionalizing double‐tetrahedral DNA probes on nanorough Ag nano‐biointerfaces, the synergetic effects of molecules and topographies improved the capture efficiency to 90.2% for SGC‐7901 cells in PBS 98 . Pei et al.…”

“… 120 The aptamer nanostructures enhance the accessibility of nucleases, enabling cell release with an efficiency of nearly 80% and a viability of 90.42%, while also maintaining molecular integrity. Similarly, Wang and colleagues utilized DNA probes for capture and nondestructive release of CTCs 98 . After capturing 90.2% of SGC‐7901 cells in PBS, 93.4% of cells were released via Zn 2+ ‐assisted DNAzyme cleavage, with the viability of post‐released CTCs reaching approximately 98.0%.…”