Polysilazanes are excellent coating materials, because of their self‐crosslinking in air at low temperatures, high chemical and thermal stability, elevated hardness, and excellent adhesion to many different substrates. Therefore, coatings of two chemically different polysilazanes (crosslinked Durazane 1800 (HTTS)/perhydropolysilazane (PHPS)) are deposited by either dip or spray coating and crosslinked at 200 or 300 °C in air to investigate the chemical composition, surface energy, and coating adhesion in dependency on the precursor type and crosslinking temperature. The silazane HTTS possesses a higher amount of nonpolar organic groups resulting in a lower surface free energy. The anti‐adherence properties are investigated by using a phenolic resin via pull‐off adhesion, which is slightly reduced from 13 MPa for uncoated aluminum to less than 10 MPa for HTTS coated substrates. The addition of different amounts of poly(tetrafluoroethylene) (PTFE) particles causes a remarkable reduction of the surface free energy leading to a strongly reduced pull‐off adhesion of less than 4 MPa of the phenolic resin from the HTTS/PTFE coated substrates. The anti‐adherent properties remain even after repeated pull‐off tests. Because of the excellent properties, the HTTS/PTFE coatings are a very suitable system for easy mold release of plastic parts from metal molds and to replace commercial nonstick PTFE coatings.

Microsystems recently have been introduced as tools for screening in modern chemistry, biochemistry and biology. It has been shown that new microsystems can be implemented in the biomedical laboratory by using the microsystemic approach for the sample carrier -the miniaturized microtiter plate (''the nanotiter plate'') -or the production of nanodroplets with ink jetters and to integrate those systems in macrodevices like xyz tables and detection devices like CCD-cameras. We show in this paper that decisive problems of the approach -the evaporation problem and the problem of chemical/biochemical/biological compatibility of the assays and the used materials can be solved successfully. It is possible to realize chemical synthesis in miniaturized flow systems and to perform isothermal amplification of RNA in silicon wafers. Furthermore real high throughput screening with in vivo systems can be performed and all relevant parameters as evaporation, pipetting and detection can be controlled on reasonable time scales.

The NanoSynTest TM -system combines screening and synthesis in a highly integrated fashion. The central feature of the experimental system are nanotiterplates with a density of 100 wells/cm 2 and a volume of roughly 0.1 ll each. The wells are equipped with a microsieve membrane for removal of liquids. Substance transfer of liquids and beads for solid phase synthesis is performed in the nl range with special adapted dispensers and sorting wafers. Thus the successfully performed adaptation of such tools to automated synthesis and screening workstations leads to experiments in synthesis, single bead analysis of synthesis products (IR spectroscopy, HPL-chromatography of single beads) and the fluometry of biological substances in nanotiterplates. These proof of principle experiments open up the way to a completely new and modular design of an integrated synthesis and screening facility based on nanoand microtechnology.

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