Effect of cell-nanostructured substrate interactions on the capture efficiency of HeLa cells.

Circulating tumor cells (CTCs) are regarded as an effective biomarker for cancer detection, diagnosis and prognosis monitoring. CTCs capture based on nanostructured substrates is a powerful technique. Some specific adhesion molecule antibody coated on the surface of nanostructured substrates, such as EpCAM, is commonly used to enhance the CTCs capture efficiency. Substrate nanotopographies regulate the interaction between the substrates and captured cells, further influencing cell capture efficiency. However, the relationship between cell capture efficiency and cell-substrate interaction remains poorly understood. Here, we explored the relationship between cell capture efficiency and cell-substrate interaction based on two sets of nanostructures with different nanotopographies without antibody conjugation. Given the urgent demand for improving the capture efficiency of EpCAM-negative cells, we used HeLa (EpCAM-negative) cells as the main targets. We demonstrated that HeLa cells could be more effectively captured by two nanostructural substrates, especially by double-layer composite nanoforests. Therefore, the morphological and migrating interaction between HeLa cells and distinct substrates was associated with cell capture efficiency. Our findings demonstrated the potential mechanism for optimizing the nanotopography for higher capture efficiency, and provide a potential foundation for cancer detection, diagnosis and treatment.