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It is well-known that protein-modified implant surfaces such as TiO2 show a higher bioconductivity. Fibronectin is a glycoprotein from the extracellular matrix (ECM) with a major role in cell adhesion. It can be applied on titanium oxide surfaces to accelerate implant integration. Not only the surface concentration but also the presentation of the protein plays an important role for the cellular response. We were able to show that TiOX surfaces modified with biotinylated fibronectin adsorbed on a streptavidin-silane self-assembly multilayer system are more effective regarding osteoblast adhesion than surfaces modified with nonspecifically bound fibronectin. The adsorption and conformation behavior of biotinylated and nonbiotinylated (native) fibronectin was studied by surface plasmon resonance (SPR) spectroscopy and atomic force microscopy (AFM). Imaging of the protein modification revealed that fibronectin adopts different conformations on nonmodified compared to streptavidin-modified TiOX surfaces. This conformational change of biotinylated fibronectin on the streptavidin monolayer delivers a fibronectin structure similar to the conformation inside the ECM and therefore explains the higher cell affinity for these surfaces.
The wireless data logger system “Cor/log® BAN BT” (CL) allows seamless 24/7 monitoring of relevant vital sign parameters. CL covers the entire period of acute point of care inside the hospital and the recovery period, when first mobility is achieved and when the patient is released into an ambulatory or homecare environment. The CL records the relevant vital signs such as ECG, respiration, pulse oximetry with plethysmogram and movement. The vital data collected with the CL data logger is saved on a memory card for further analysis and is simultaneously transmitted in real-time to a telemedicine server via a smartphone or tablet. The smartphone also provides GPS location information. In addition Cor/log View, an Android Application for viewing recorded vital sign data originating from the CL, was developed. CL has also a connector to the generic MedM health cloud. MedM is a generic patient data management system (PDMS) consisting of a cloud portal and a mobile health app. The app runs on Android, iOS and Windows. The app can connects wirelessly to the CL physiologic monitor and stores the vital signs in the cloud.
Creating chemo- & bioinformatics workflows, further developments within the CDK-Taverna Project
(2008)
To achieve high temperature stable insulation materials for the electrical insulation of fine copper wires two different bis(alkoxysilylalkyl)pyromellitamide acids 1 and 2 were prepared. These organic–inorganic sol–gel hybrid precursors were obtained via reactions of pyromellitic dianhydride and alkoxysilylalkylamines. The molecular single-source precursors 1 and 2 were comprehensively studied using FT-IR, 1H, 13C and 29Si NMR spectroscopy as well as elemental analyses. Besides, the hydrolysis and condensation processes of the different precursors were examined with solution 29Si NMR spectroscopy. The imidization process was investigated using 13C NMR spectroscopy, FT-IR spectroscopy as well as thermal analysis methods. The different precursors were applied to coat fine copper wires using an industrial coating device. The obtained coatings were cured at temperatures between 380 and 425 °C, and tested regarding thicknesses, number of pinholes, electrical breakdown voltage and elongation. FT-IR spectroscopy was used to determine the chemical structure and scanning electron microscopy to investigate the morphology of the coating materials. The obtained coatings showed very promising mechanical, thermal and electrical properties, i.e. highest breakdown voltage values well above 200 V/µm. They possess high flexibility without cracking and no pinholes or other defects were detected.
The biomodification of surfaces, especially titanium, is an important issue in current biomedical research. Regarding titanium, it is also important to ensure a specific protein modification of its surface because here protein binding that is too random can be observed. Specific nanoscale architectures can be applied to overcome this problem. As recently shown, streptavidin can be used as a coupling agent to immobilize biotinylated fibronectin (bFn) on a TiOX surface. Because of the conformation of adsorbed biotinylated fibronectin on a streptavidin monolayer, it is possible to adsorb more streptavidin and biotinylated fibronectin layers. On this basis, an alternating protein multilayer can be built up. In contrast to common layer-by-layer technology, in this procedure the mechanism of layer adsorption is very specific because of the interaction of biotin and streptavidin. In addition, we showed that the assembly of this multilayer system and its stability are dependent on the degree of labeling of biotinylated fibronectin. Hence we conclude that it is possible to build up well-defined nanoscale protein architectures by varying the degree of labeling of biotinylated fibronectin.