Bioactive Silk-Like Protein Polymer Films on Silicon Devices

Abstract

ABSTRACTCoatings of genetically engineered protein polymers based on the crystalline segment of B. Mori silk fibroinand cell binding domains from extracellular matrix proteins (ProNectin™ by Protein Polymer Technologies, Inc.) were applied to bare silicon wafers used to mimic microcircuit devices. These silicon devices have applications in the stimulation and monitoring of central nervous system activity but need bioactive coatings for integration into nervous tissue. Gel point coating technology was developed by preparing solutions at the onset of phase separation in protein polymer/formic acid/ ethanol systems. Dipping silicon wafer substrates into such solutions produced homogeneous thin protein polymer coatings. Quench coating techniques that create rough surfaces in a controlled manner were explored by driving protein polymer solutions through different regions of the protein polymer/formic acid/methanol system before drying. Atomic force microscopy was used to characterize the protein films.