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The synthesis and structural characterization of the first dilithium salt of a tetrahydroxydisiloxane, [DmpSi(OH)OLi]2O (6), is described (Dmp = 2,6-dimesitylphenyl). The solid state structure reveals the presence of a dimeric motif where two disiloxane units are linked by coordinating lithium atoms which differs from those found for the sodium and potassium analogs. The arrangement imposed by the cluster formation leads to diastereomeric silicon atoms exhibiting (R,S) configuration in the solid state. In addition, the intermediates of the reaction, monolithiated and dilithiated silanetriol could be identified by means of high-resolution mass spectrometry and the formation of 6 is discussed. Moreover, the fully protonated tetrahydroxydisiloxane, [DmpSi(OH)2]2O has been obtained as well and its solid state structures with varying hydrogen bond acceptors have been surveyed.

The anticoagulant activity of surfaces decorated with cellulose nanocrystals (CNCs) prepared via sulfuric acid hydrolysis, is explored. Such surfaces bear a high amount of negatively charged sulfate groups, which mimic the naturally occurring anticoagulant heparin in terms of charge density. It is demonstrated that CNC decorated surfaces significantly enhance the coagulation times of blood plasma and whole blood as proven by QCM-D and simple clotting tests.

The formation of t-butyl substituted polyhedral silsesquioxanes (POSS) starting from the corresponding silanetriol is reported. Several intermediates involved in this complex condensation process could be identified spectroscopically. In addition, the initial condensation intermediate t-Bu(2)Si(2)O(OH)(4), as well as t-Bu(6)Si(6)O(9) and t-Bu(7)Si(7)O(9)(OH)(3), could be characterized by X-ray crystallography. Owing to the high crystal quality it was possible to experimentally determine the geometric parameters of the unusual cyclic hydrogen bond network in a dimeric POSS trisilanol for the first time. Furthermore, we investigated the structural changes concomitant with dimer formation/dissociation of the t-butyl substituted POSS trisilanol and its methyl analogue.

The first gas phase structure of a silanetriol, tert-butylsilane-triol [(t)BuSi(OH)(3)], determined by gas electron diffraction (GED), is reported. Quantum chemical calculations have been performed to elucidate potential intermolecular interactions between silanetriol molecules in the gas phase. The results are set into contrast to solid state structures of (t)BuSi(OH)(3) and related compounds.

The rational design of silver nanoparticles encapsulated in an anticoagulant, hemocompatible polysaccharide, 6-O-chitosan sulfate, is presented. Three different approaches are described for the immobilization of these core shell particles on cellulosic surfaces. The mass of the immobilized particles is quantified using a quartz crystal microbalance with dissipation (QCM-D). The antimicrobial activity of the surfaces towards E. coli MG 1655 [R1-16] is investigated by live/dead assays using fluorescence staining. All surfaces treated with the designed nanoparticles exhibit excellent antimicrobial activity towards E. coli MG 1655 [R1-16]. Anticoagulant properties of blood plasma on the nanoparticle treated surfaces have been determined using QCM-D. In comparison with the unmodified substrates, the total coagulation time as well as the thrombin formation time and fibrin clotting time of surfaces modified with nanoparticles are significantly increased.

The behavior of amorphous cellulose model thin films upon heat treatment is investigated. Upon heat treatment, a structural rearrangement in the films from a featureless to a fibrillar structure is observed which correlates with the regeneration time and total cellulose content as proven by atomic force microscopy and X-ray photoelectron spectroscopy. ATR-IR spectroscopy proves the presence of stronger hydrogen bonds in the heat treated surfaces which originate from a reorganization of the cellulose chains and pore structure. The rearrangement is accompanied with an increased surface hydrophobicity, a reduced swelling capacity and a reduction in the water content of the films. An increase in crystallinity of the films is not observed.