Reversible capture and release of circulating tumor cells on a three‐dimensional conductive interface to improve cell purity for gene mutation analysis

• Published in: View (Beijing, China) Vol. 4; no. 1
• Main Authors: Wang, Yi‐Ke, Wang, Ming, Cheng, Shi‐Bo, Chen, Yi‐Jing, Li, Cui‐Wen, Xie, Min, Huang, Wei‐Hua
• Format: Journal Article
• Language: English
• Published: Beijing John Wiley & Sons, Inc 01.02.2023; Wiley
• Subjects: Biomarkers; Biopsy; Biotechnology; Blood; Cancer; circulating tumor cells; conductive scaffold; gene mutation analysis; microfluidic chip; Microscopy; Monoclonal antibodies; Mutation; purity; reversible capture and release; Semiconductors; Tumors; Beijing China; China
• ISSN: 2688-3988; 2688-268X; 2688-268X
• DOI: 10.1002/VIW.20220054

Rare circulating tumor cells (CTCs) are always harvested with large numbers of white blood cells (WBCs) by current CTC isolation techniques, which influences the accuracy of CTC‐related gene and protein analysis. Therefore, it is very urgent to develop a method for efficient isolation of CTCs with high purity. In this work, we fabricated a reversibly assembled interface by layer‐by‐layer assembly of biotinylated poly‐(L‐lysine‐graft‐ethylene glycol) (PLL‐g‐PEG‐biotin), streptavidin, and CTC‐specific antibody on a three‐dimensional conductive scaffold, and further embedded it into a customized microchip for CTC capture. The assembled multilayers increased the roughness of the scaffold, which improved the capture efficiency. Importantly, the PLL‐g‐PEG‐biotin covalently coupled with CTCs could be detached from the scaffold by electrostatic repulsion, and the released CTCs could be recaptured on the conductive scaffold via electrostatic attraction while the WBCs were continuously drifted away. This reversible capture and release strategy significantly improved the purity of CTCs, and pure CTCs were obtained from cancer patients’ blood samples for gene mutation assay, which will be of great significance for assisting cancer diagnosis and treatment in a noninvasive way. Rare circulating tumor cells (CTCs) are always co‐collected with large numbers of blood cells, influencing the accuracy of CTC‐related downstream analysis. Here, a new type of 3D scaffold microchip with biofunctionalized conductive interface was prepared for the reversible capture and release of CTCs, which highly improved the purity of CTCs. This method has been successfully applied to cancer patients’ blood samples and ultrapure CTCs were obtained for gene mutation assay, benefiting cancer diagnosis in a noninvasive way.