Multiple microarrays of non-adherent cells on a single 3D stimuli-responsive binary polymer-brush pattern.

We have developed a 3D smart binary polymer-brush pattern on the polymer substrate for inducing multiple cell microarrays aided by a lectin and temperature. The binary polymer-brush pattern composed of poly(N-isopropylacrylamide) (PNIPAM) and poly(d-gluconamidoethyl methacrylate) (PGAMA) brushes is fabricated by combining the photolithography technique with a surface-initiated photo-polymerization (SIPP) method. We demonstrate that well-defined binary polymer-brush patterns with high resolution are fabricated using this facile method. The patterned hierarchical PNIPAM brushes exhibit reversible switching to the adhesion of red blood cells (RBCs) induced by thermo-responsiveness. The PGAMA brush domains resist adhesion of RBCs but bind specifically with concanavalin A (Con A), forming a lectin pattern to capture RBCs in a site-specific manner. Therefore, multiple cell microarrays on a single platform are generated with the aid of Con A and temperature. This novel platform composed of a smart binary polymer-brush pattern is versatile and specific, which opens up pathways to potential applications such as microsensors, biochips and bioassays.