Separation and subsequent culturing of MCF-7 breast cancer cells on self-assembled protein-coated magnetic beads in a microfluidic chip is demonstrated. The beads were patterned in situ inside a sealed microfluidic channel using magnetic-field-assisted electrostatic self-assembly. Hereafter, they were grafted by exposure to a solution of 5D10 monoclonal antibodies (mAb) and fibronectin (FN), with the first being used for immunospecific cell capture and the latter being used for cell adhesion and growth. A solution of target MCF-7 cells mixed with Jurkat cells was brought inside the microchannel, leading to specific MCF-7 cell capture; the latter were then cultured and evidenced by cell immuno-luminescence.