6421 28 26652 Semiconductor nanoparticles (so-called 'quantum dots ', QDs) are investigated for about 20 years because of their unique fluorescent and semiconductive properties. QDs were mainly used for analytical systems outside and inside a living organism. However, for most of these analytical systems, surface of QDs has to be modified. Immobilization techniques for semiconductor nanoparticles are showing wide interests within solar-cell technologies and biosensor development. A functional inorganic/organic hybrid nanosystem could be realized by combination of an inorganic synthesis of semiconductor nanoparticles with commonly used amino acid chemistry on the surface of extremely hydrophilic aluminium oxide filter membranes. 3-Aminopropyle-triethoxysilane (APTES), allyloxytrimethylsilane and Fmoc-(S-t-Bu)-cystine were used for surface modification. After cleavage of protective groups Fmoc and t-Bu, semiconductor nanoparticles were immobilized by self-assembly on filter surface. The immobilization can be explained according to commonly used ligand-exchange reactions. This technique results in strongly fluorescent surfaces presenting an additional amino-group for further functionalization. The obtained membranes are suitable for various diagnostic applications like multi-parameter immunoassays and array applications at nanoscale.

For the development of site specific liposomes, high stability and long circulation properties are very promising for the improvement of drug targeting and drug delivery system as well as improvement of bioavailability of efficient bioactive drugs. Tetraether lipids (TELs) are very stabile lipids, extracted from Thermoplasma acidophilum. Because of its high chemical stability and its biocompatibility, Tetraether lipid liposomes prepared with TELs are excellent candidates for liposomal drug delivery. In this study a model protein, Concanavalin A (ConA) was chosen for a simulation of a specific adsorbtion onto mannan surface. Concanavalin A (ConA) is a lectin, extracted from Canavalia ensiformis, which interacts with sugar domains localized on inflammatory active tissues or tumors. In this study, stable TEL liposomes were prepared and characterized. Furthermore to develop side specific liposomes, tetraether lipids were activated and, ConA was covalently bond onto the surface of the prepared liposomes. Interaction of ConA conjugated liposomes with mannan‐modified surfaces was investigated by Biomolecular Interaction Analysis (BIA) via Reflectometric Interference Spectroscopy (RIfS). This provides real time observation of interactions between carbohydrate structure and TEL liposomes. Specific interaction was also visualised by AFM imaging subsequent to the RIfS measurements. According to the results, with ConA conjugated liposomes, high specific adsorption efficiency was observed. Consequently, this specific adsorption assay between ConA and mannan surface can be considered as a model for the further studies utilized with specific biomarkers for a selective active agent transfer to tumors and inflammatory active tissues. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

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