Fabrication of Adhesive Protein Micropatterns In Application of Studying Cell Surface Interactions

The development of techniques for immobilizing biomolecules on solid surfaces has attracted wide attention because of the broad potential applications of biofunctionalized surfaces in stem cell biology, tissue engineering, biosensor technology, and high-throughput screening for drug discovery. In particular, protein micropatterns on surfaces provide unprecedented spatial resolution to control cell shape and direct cell behavior. Combining with optical methods and functional assays, micropatterning techniques are one of the key tools for investigating cell molecular and mechanical mechanisms in basic cell behaviors, such as cell adhesion, cell migration, cell division and differentiation. In this work, we use a photolithographic approach to create cell adhesive micropatterns. We have designed different geometries to control and study cell adhesion. A pre-designed mask is fabricated for the photolithographic process. The designed features are transferred to a glass substrate by UV exposure of a protein solution containing a photoinitiator through the mask. Typically, patterns of fibronectin are produced in a nonadhesive background of poly-L-lysine grafted poly (ethylene glycol). Cells seeded on these substrates, can specifically adhere and spread on the adhesive protein micropatterns and display unique shapes according to the contour and size of the pattern.