Detection and Separation of Circulating Tumor Cells Using Magnetic Fluorescent Nanoparticles.

Circulating tumor cells (CTCs) have emerged as indispensable biomarkers in liquid biopsy, offering critical insights for early cancer diagnosis, therapeutic monitoring, and prognostic evaluation. Current immunomagnetic separation methods are prized for their operational simplicity, high specificity, and favorable sensitivity; however, they contend with several significant drawbacks, including the need for complex ligand modification, suboptimal capture efficiency of heterogeneous CTC populations, and the risk of impairing cell viability during subsequent analytical procedures. To address these limitations, we have developed a novel core-shell magnetic fluorescent nanoparticle (FR@Z-pTA NPs) by integrating an Fe3O4 magnetic core with a ZIF-8 shell and tannic acid coating. These engineered nanoparticles facilitate broad-spectrum, high-efficiency capture and in situ fluorescent labeling of diverse CTCs while remaining responsive to both pH and ATP stimuli, enabling mild, non-destructive release of intact cells. By preserving cell viability and improving downstream analytical reliability, this innovative nanoplatform opens new avenues for the clinical implementation of CTC-based liquid biopsy.