A method for selecting aptamers with target cell binding specificity in a microfluidic device platform for co-culture of multiple cell cultures, the method comprising co-culturing cancerous target cells and non-cancerous non-target cells explanted from patients in an arrangement of microfluidic devices,
- wherein the co-culturing of the cancerous target cells and the non-cancerous non-target cells is carried out in a closed modular arrangement system with fluid circulation guided by combinations of microfluidic devices connected in parallel, in series, or a combination thereof;
- and
- wherein a step of injecting an aptamer combinatorial library in said closed system is carried out after a homeostatic balance has been established between the cancerous target cells and the non-cancerous non-target cells, and fluid components circulating through the closed system.