Denaturing and refolding of protein molecules on surfaces.

Keeping protein molecules in the active state on a solid surface is essential to protein microarrays and other protein-based biosensors. Here, we show that the 2-D chemical environment controls the refolding of the denatured green fluorescent proteins tethered to solid surfaces. Refolding occurs readily on the repulsive PEG functionalized surface but is inhibited on the attractive--NH(2) functionalized surface. This result shows the critical importance of the 2-D chemical environment in the maintenance and revival of protein activity on surfaces and opens the door to designing 2-D molecular chaperones for protein folding.