Microfabricated quill-type surface patterning tools for the creation of biological micro/nano arrays

Novel quill-type cantilever-based surface patterning tools (SPTs) were designed and constructed for use in controlled placement of femtoliter volumes of biological molecules on surfaces for biological applications. These tools were fabricated from silicon dioxide using microelectromechanical systems (MEMS) techniques. They featured a 1 microm split gap, fluidic transport microchannels and self-replenishing reservoirs. Experimental trials were performed using these tools on NanoArrayer molecular deposition instrumentation. Cy3-streptavidin was loaded as a biological sample and patterned on an amine-reactive dithiobis-succinimidyl undecanoate (DSU) monolayer on gold. Results showed these tools were capable of generating high quality biological arrays with routine spot sizes of 2-3 microm. The spot size could potentially achieve sub-micron dimensions if these SPT designs are reduced in size by more precise microfabrication techniques. The geometric designs of these tools facilitated sample replenishment from the local reservoir on the cantilever which allowed printing of large numbers of spots without sample reloading.