Deposition and characterisation of Langmuir-Blodgett films of an azo-modified polypeptide : azobenzene-containing poly-L-lysine

Langmuir-Blodgett (LB) films of a photosensitive polypeptide, prepared by i ntroducing 31 mol% azobenzene moieties into the side chains of poly-L-lysin e, have been deposited and studied using circular dichroism, infrared spect roscopy. X-ray reflection and surface plasmon resonance. The macroscopic st ructure of freshly prepared LB films consists of deformed polypeptide helic es arranged in layers, with a layer thickness of about 2.0 nm. Infrared mic roscopy measurements in polarised light reveal some local order which decre ases with increasing film thickness. (C) 1998 Elsevier Science S.A. All rig hts reserved.