Controlled vapor deposition approach to generating substrate surface energy/chemistry gradients.

Substrate surface energy/chemistry gradients provide a means for high-throughput exploration of the surface interactions that are important in many chemical and biological processes. We describe the implementation of a controlled vapor deposition approach to surface modification that enables the facile production of substrate surface energy/chemistry gradients while maintaining versatility in both the gradient profile and the surface chemistry. In our system, gradient formation relies on the cross-deposition of functionalized chlorosilanes onto the substrate surface via vaporization of the deposition materials from liquid reservoirs under dynamic vacuum.