Microfluidic Electrochemical Sensor Array for Characterizing Protein Interactions with Various Functionalized Surfaces

• Published in: Analytical chemistry (Washington) 2011-08, Vol.83 (15), p.5920-5927
• Main Authors: Dykstra, Peter H, Roy, Varnika, Byrd, Christopher, Bentley, William E, Ghodssi, Reza
• Format: Article
• Language: English
• Subjects: Adsorption; Analytical chemistry; Animals; Biological and medical sciences; Biosensing Techniques - methods; Biosensors; Biotechnology; Cattle; Chemistry; Cyclic AMP Receptor Protein - chemistry; Cyclic AMP Receptor Protein - metabolism; Electrochemical Techniques - methods; Electrodes; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; General, instrumentation; Lymphotoxin-alpha - chemistry; Lymphotoxin-alpha - metabolism; Methods. Procedures. Technologies; Microfluidic Analytical Techniques - instrumentation; Microfluidic Analytical Techniques - methods; Polyethylene Glycols - chemistry; Protein Interaction Mapping; Proteins; Serum Albumin, Bovine - chemistry; Serum Albumin, Bovine - metabolism; Surface chemistry; Surface Properties; Tumor Necrosis Factor-alpha - chemistry; Tumor Necrosis Factor-alpha - metabolism; Various methods and equipments
• ISSN: 0003-2700; 1520-6882
• DOI: 10.1021/ac200835s

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 successfully passivate against nonspecific binding 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 three commonly used passivation compounds (mercaptohexanol, polyethylene glycol, and bovine serum albumin) and demonstrates their interaction with three commonly studied proteins in genetic and cancer research (cAMP receptor protein, tumor necrosis factor α, and tumor necrosis factor β). The ability to quickly characterize various surface interactions provides knowledge for selecting optimal functionalization for any biosensor.