A Magnetic Dynamic Micro-Biointerface with Biofeedback Mechanism for Cancer Cell Capture and Release.

Abstract

Dynamic biointerfaces with reversible surface bioactivities enable dynamic modulation of cell-material interactions, thus attracting great attention in biomedical science. Herein, we demonstrated a paradigm shift of dynamic biointerfaces from macroscopical substrates to micron-sized particles by reversible engineering a phenylboronic acid (PBA)-functionalized magnetic microbead with mussel-inspired cancer-cell-targeting peptide. Due to reversible catechol-boronate interactions between the peptides and microbeads, the micron-sized dynamic biointerface exhibited sugar-responsive cancer-targeting activity, showing the potential as a micro-platform for magnetic and non-invasive isolation of cancer cells through natural biofeedback mechanism (e.g., human glycemic volatility). Our results demonstrated that the dynamic magnetic platform was capable of selective cancer cell capture (~85 %) and sugar-triggered release of them (> 93 %) in cell culture medium with high efficiency. More importantly, by using this platform, a decent number of target cells (~23 on average) could be magnetically isolated and identified from artificial CTC blood samples (1 mL) spiked with 100 cancer cells. In view of the biomimetic nature, high capture efficiency, excellent selectivity, and the superiority in cell separation and purification processes, the dynamic magnetic micro-platform reported here would be a promising and general tool for rare cell detection, separation and cell-based disease diagnosis.