Physical vapor deposition of peptide nanostructures

Abstract

Biological units such as proteins and peptides have the intrinsic ability to self-assemble into natural biological nanostructures such as DNA strands, proteins and amyloid fibers. These assemblies have become an inspiration for development of new supramolecular nanostructural materials self-assembled from chemically synthesized peptides and proteins. Bioinspired materials are in the center of interest in research and development, as they are considered as a new generation of functional soft materials, which can be used in a variety of applications. Peptide nanostructure deposition technology is a key problem in the emerging field of bottom-up nanotechnology of these bioinspired nanomaterials. It has been mainly performed by solution deposition or by a vapor transport method. In this study, we describe a new technique of physical vapor deposition (PVD) of biomolecules compatible with microelectronic technology allowing fabrication of dense and homogeneous peptide nanostructural materials. We present a deep insight into the self-assembly mechanism of peptide nanostructures deposited by our developed PVD technique, a study of their elementary growth stages by investigation of fine morphological and packing structure, molecular composition, and their chemical and physical properties. These have enabled us to develop a controllable deposition technology for fabricating peptide nanostructures. A detailed study of physical vapor deposition (PVD) technique applied to diphenylalanine (FF) peptides is described, following the self-assembly mechanism of deposited peptide nanostructures.Control of their chemical and physical properties have enabled us to develop a controllable deposition technology for fabricating peptide nanostructures. The PVD process of FF consists of elementary stages: first linear-FF (L-FF) molecules adhere to the substrate forming an amorphous layer, which grows into nanoclusters. Second, either PNT of L-FF or peptide nano fiber of cyclo-FF are formed, depending on the PVD environment.