Self-assembled films, supramolecular nanotechnology

In this chapter we describe the basic principles involved in the controlled production and modification of two-dimensional protein crystals. These are synthesized in nature as the outermost cell surface layer (S-layer) of prokaryotic organisms and have been successfully applied as basic building blocks in a biomolecular construction kit. Most importantly, the constituent subunits of the S-layer lattices have the capability to recrystallize into iso-porous closed monolayers in suspension, at liquid-surface interfaces, on lipid films, on liposomes, and on solid supports (e.g., silicon wafers, metals, and polymers). The self-assembled monomolecular lattices have been utilized for the immobilization of functional biomolecules in an ordered fashion and for their controlled confinement in defined areas of nanometer dimension. Thus, S-layers fulfill key requirements for the development of new supramolecular materials and enable the design of a broad spectrum of nanoscale devices, as required in molecular nanotechnology, nanobiotechnology, and biomimetics [1-3]. 

The inherent ability of block copolymers to self-assemble into various well-ordered supramolecular structures makes them attractive for numerous technological applications. For instance, thin films self-assembled from block copolymers have been used as building blocks in nanotechnology and materials science [89-91 ]. Block copolymers have been employed directly without further manipulation as nanomaterials [92], or used as self-organized templates for the creation of nanos-tructured materials [92, 93]. Block copolymer blends demonstrated their applicability as patterning templates for the fabrication of well-ordered arrays [94], as well as for nanoscale manufacturing of more complex patterns [95]. The use of amphiphilic block copolymers for templating applications has been reviewed by FOrster [96]. 

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