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We report on a novel approach to identify genetic variations based on the detection of specific polymerase-chain-reaction products by surface plasmon resonance. We use a recently developed, home-made spectrometer which exploits chips with integrated optics and microfluidics. The gold film at the chip surface is locally functionalized with single-stranded, thiol-modified probe DNA by applying a nanoliter dispenser. We discuss the chemical conditions for the achievement of maximum SPR signal strength and spot array density, and evaluate the SPR detection of selective binding of a set of 17 PCR products

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The catalytic properties of highly dispersed, bacterial surface layer supported nanoscale platinum clusters immobilized at alumina particles are studied with respect to carbon monoxide oxidation. Compared to samples prepared from platinum impregnated alumina, the templated metal clusters are catalytically active at lower temperatures. The catalytic behaviour of the samples is discussed with respect to their cluster morphology studied by TEM.

Self‐assembling surface layer (SL) proteins of bacteria have been widely studied, in particular their use as molecularly defined, 2D coatings of technical surfaces. An important prerequisite is the availability of a sufficient amount of protein. However, a detailed and optimized protocol for the complete SL extraction is so far not available. Here, we describe the complete purification and reassembly procedure of an SL protein of Lysinibacillus sphaericus NCTC 9602, starting from the cultivation of cells, the preparation and purification of SL proteins up to the long‐term storage and in vitro self‐assembly of the proteins. All crucial steps of the procedure are assessed by different microscopic techniques, such as light microscopy, atomic force microscopy, and scanning electron microscopy as well as by SDS‐PAGE as a biochemical method. We demonstrate that storage of the protein in the presence of sodium azide or upon lyophilization allows the preservation of the self‐assembly properties for at least 9 years. Additionally, we describe a method allowing the extraction of intact flagella with lengths in the range up to 4 μm. Flagella may have applications in bio‐nanotechnology, for example as templates for metallic nanowires.

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To achieve a regular quadratic particle arrangement, gas phase prepared FePt nanoparticles which were annealed in flight in order to obtain the highly anisotropic tetragonal 1 0 structure are deposited onto the regular 2-D bacterial surface-protein layer (S layer) of Bacillus sphaericus NCTC 9602 which exhibits a four-fold lattice symmetry with a lattice constant of 12.5 nm. The degree of regularity is studied by the statistical evaluation of the particles positions observed by transmission electron microscopy. Although the obtained regularity for the annealed hard magnetic particles is less than for previously studied disordered fcc FePt nanoparticles, a template-directed transfer of both lattice symmetry and periodicity from the 2-D protein crystal to the particle arrangement is observed. In addition, particle agglomeration which has been shown to have a strong effect on the arrangement's regularity, is clearly reduced for the annealed particles because of the mutual magnetic repulsion of adjacent particles.