Described herein is a beads-free bioprocessor as an automated and cost-effective T cell processing and manufacturing platform. T cells are a core component in CAR T cell therapies for cancer treatment, but are difficult to manufacture to scale in clinically relevant quantities. The 3D bioprocessor provides an alternative device that is scalable, beads-free, easy-to-use, and cost-effective for using CAR T cell therapy in cancer immunotherapy. Besides CAR T cell application, this platform technology has potential for many other applications such as cancer cell isolation.