Laser and Interfacial Nanoengineering of the S-Layer/Solid System

Wolfgang Kautek1, Angela Neubauer2, and Uwe. B. Sleytr3

1Laboratory for Thin Film Technology, Federal Institute for Materials Research and Testing, Unter den Eichen 44-46, D-12205 Berlin, Germany,
2Nanosearch Membrane GmbH, Hettenkofergasse 13/45, A-1160 Vienna, Austria, and
3Center for Ultrastructure Research, Ludwig Boltzmann Institute for Molecular Nanotechnology, University of Agricultural Sciences, Gregor-Mendel-Str. 33, A-1180 Vienna, Austria



Two-dimensional crystalline bacterial cell protein surface layers (S-layers) on solid substrates are of fundamental and technological interest in biotechnology, biomineralization, biosensorics, and bottom-up nanostructuring technologies. Their recrystallization, deposition, delamination and electrochemical modification on various solid substrates has become the object of intensive research. A study with the electrochemical quartz-microbalance, the scanning force microscope, and ex-situ x-ray photoelectron emission spectroscopy measurements at emersed electrode systems showed that electrochemical processes control the bonding conditions between the S-layer biomolecules and the substrate. Besides such fundamental investigations, international interdisciplinary projects with substantial industrial involvement have been undertaken. Nanometer-range calibration artefacts on the basis of S-layer templates for scanning probe microscopes were approached with electrochemical template deposition combined with pulse-laser and electron beam deposition. S-layers have been and are being also employed as immobilization matrices for binding biologically functional molecules on solid surfaces. Pulse-laser deposition of precious metals under inert gas conditions allowed to establish e.g. efficient electronic contacts on S-layer based enzyme electrodes in amperometric sensors. An outlook will be presented about the potentials of laser and interfacial electrochemical nanoengineering of S-layer/solid systems.