Surface engineering with poly(ethylene glycol) photolithography to create high-density cell arrays on glass

This manuscript presents a microfabrication-derived approach for controlling mammalian cell−surface interactions. Poly(ethylene glycol)-diacrylate (PEG-DA) was patterned, in a process analogous to photolithography, to manufacture high-density arrays of micrometer-scale PEG hydrogel wells on glass. Individual wells consisted of PEG walls and glass attachment pads; thus, as a result of the biological inertness of PEG, microwell patterning created a highly ordered biointerface with modulating-cell or protein-repellent properties. Fabricated hydrogel microstrucures proved very effective in guiding and confining adhesion of transformed 3T3 fibroblasts and primary rat hepatocytes to defined regions on the glass substrate. PEG-patterned glass surfaces were selectively modified with collagen (type I) to induce hepatocyte attachment. Localization of the fluorescein-conjugated collagen within the glass attachment pads of PEG hydrogel microwells was visualized by fluorescence microscopy. Further surface analysis was...