Capture and Selective Release of Viable Circulating Tumor Cells.

Selectively capturing and releasing viable circulating tumor cells (CTCs) from the peripheral blood of cancer patients is advantageous for investigating the molecular hallmarks of metastasis and developing personalized therapeutics. CTC-based liquid biopsies are flourishing in the clinical setting, offering opportunities to track the real-time responses of patients during clinical trials and lending accessibility to cancers that are traditionally difficult to diagnose. However, CTCs are rare compared to the breadth of cells that reside in the circulatory network, which has encouraged the engineering of novel microfluidic devices. Current microfluidic technologies either extensively enrich CTCs but compromise cellular viability or sort viable CTCs at low efficiencies. Herein we present a procedure to fabricate and operate a microfluidic device capable of capturing CTCs at high efficiencies while ensuring high viability. The microvortex-inducing microfluidic device functionalized with nanointerfaces positively enriches CTCs via cancer-specific immunoaffinity, while a thermally responsive surface chemistry releases the captured cells by raising the temperature to 37 °C.