Application of infrared spectroscopy for structural analysis of thin molecular films under electrochemical control

In this work in situ spectroscopic studies aiming at the determination of the structure of biomolecules in multicomponent supramolecular assemblies under electrochemical control are described. Biological membranes or extracellular matrix protein films are bioaggregates, which have a complex composition and structure. Therefore, their models are used in biomimetic studies. Methods of the preparation of biomimetic models of biological membranes are reviewed. Structure sensitive techniques applicable for the analysis of models of biological membranes are described. Due to a well-defined orientation of biomolecules in their biological assemblies, high electric fields appear at their surfaces. The deposition of models of biologically relevant assemblies on electrode surfaces ensures their exposition to physiological electric fields. Electrochemical methods provide the information concerning the stability, compactness and permeability of model membranes. However, they are not suitable for the analysis of the structure of molecules adsorbed on electrode surfaces. In order to provide the structure of molecules adsorbed on an electrode surface, a surface analyzing technique has to be adapted to probe in situ the metal liquid interface. Infrared spectroscopy techniques applicable for structural analyses of biomolecules in various supramolecular assemblies adsorbed on an electrode surface are described.