Surface characterization of porous, biocompatible protein polymer thin films

Genetically engineered protein polymer coatings are intended to improve the performance of implantable neural prosthetic devices. To facilitate device integration with tissue, three-dimensionally structured protein polymer fi lms were deposited on the devices using electrostatic atomization and gas-e volution foaming. Periodic features and the length-scale dependence of the surface roughness were identified in topographic data collected using scann ing probe microscopy. Using the power spectral density of surface data, the influence of process parameters on the surface roughness of protein polyme r thin films was examined. Details of surface topography are known to influ ence biological behavior, and the method presented was capable of quantifyi ng the evolution of surface features at biologically relevant length scales . This study provides a means for the quantitative exploration of the effec ts of topography on the performance of these devices and on biocompatibilit y in general. (C) 2001 Elsevier Science Ltd. All rights reserved.