A microfluidic electrochemical sensor array for characterizing protein interactions with various surface chemistries

We present a unique microfluidic platform to allow for quick and sensitive probing of protein adsorption to various functionalized surfaces. The ability to tailor a sensor surface for a specific analyte is crucial for the successful application of portable gas and fluid sensors and is of great interest to the drug screening community. However, choosing the correct surface chemistry to either block or bind biomolecules typically requires repeated trial and error experiments. The presented device incorporates an array of integrated electrochemical sensors for fast, sensitive, label-free detection of these binding interactions. The layout of the electrodes allows for loading various surface chemistries in one direction while sensing their interactions with particular compounds in another without any cross contamination. Impedance data is collected for two commonly used surface assembled monolayer (SAM) compounds, and demonstrates their interaction with a common bacterial gene regulator, cyclic adenosine monophosphate (cAMP) receptor protein (CRP). The ability to quickly characterize various surface interactions provides knowledge for selecting optimal functionalization for any biosensor.