Protein microarrays on ITO surfaces by a direct covalent attachment scheme

We describe the use of an indium tin oxide (ITO) thin film on a solid support serving as an effective generic immobilization platform to achieve one-step direct covalent attachment of arrayed proteins with good reproducibility and uniformity. Potential functional analyses on these surfaces involving protein-protein and protein-ligand interactions have been demonstrated. We also show that the approach can be adapted, via a photolithography-derived microwell route, to produce high-density protein microarrays which typically could accommodate a significantly higher density while occupying a comparatively smaller footprint than that achievable using currently existing high-precision robotic microarrayer systems, suggesting its potential applications in simultaneous parallel biological assays.