Plasma Polymerized Pyrrole Films for Biological Applications: Correlation Between Protein Adsorption Properties and Characteristics

The present work describes the fabrication, characterization, and optimization of plasma polymerized pyrrole films, PPpy, prepared by continuous wave for application as the adhesion layers of bovine serum albumin (BSA). Plasma conditions used throughout the work produced significant differences in the chemical, physical, and electrochemical properties of the resultant PPpy films. Structural analysis and property characterizations of PPpy were carried out using Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and electrochemical workstation. Surface plasmon resonance spectroscopy was used to investigate the adsorption kinetics of BSA onto PPpy films. Moreover, when immersed in solutions or after BSA adsorption, the differences of electron transfer at the interfaces between the PPpy and the electrolyte solutions were determined by electro impedance spectroscopy. While there is a clear dependence of the protein adsorption affinity on the plasma polymerization condition employed during the film preparation. The relationship between film structure, electrochemical properties, polymer stability in aqueous buffer, and protein binding affinities are discussed.