REFLECTION-ABSORPTION FOURIER-TRANSFORM INFRARED-SPECTROSCOPY (RAIRS) STUDY OF THE CONFORMATION AND ORIENTATION OF POLY(AMINO ACID) LANGMUIR-BLODGETT-FILMS

A quantitative study by reflection-absorption infrared spectroscopy (RAIRS) on multilayer systems of Langmuir-Blodgett (LB) poly(amino acid) films has been carried out. Thickness measurements of monolayer and multilayer systems have been made and the results obtained by two well-known equations have been compared. Evolution of the alpha-helix conformation as a function of temperature in the case of polybenzyl aspartate (PEA) and polybenzyl glutamate LB systems has also been studied by RAIRS. Finally, a Fourier transform infrared transmission study on PEA LB multilayers as a function of temperature has allowed us to draw some conclusions on the orientation of the C=O bonds (amide I) with respect to the dipping direction.