In Situ ATR‐FTIR Spectroscopy on the Deposition and Protein Interaction of Polycation/Alginate Multilayers

Abstract We report in situ ATR‐FTIR spectroscopy studies of the deposition of biocompatible polyelectrolyte multilayers (PEMs) consisting of the polycation chitosan (CHT) or poly(ethyleneimine) (PEI) and the polyanion sodium alginate (ALG) and their interactions with model‐protein human serum albumin (HSA). HSA‐adsorption data for PEI/ALG and CHT/ALG PEMs show the importance of the outermost polyelectrolyte (PEL) layer for protein interactions: CHT‐ or PEI‐terminated PEMs are highly attractive to HSA, while ALG‐terminated PEMs are repulsive, relevant for the generation of protein‐active or protein‐inert biomedical surfaces. The bound HSA is found to be located at the surface rather than the inner region of the PEM.