Low-density PDMS foams by controlled destabilization of thixotropic emulsions.

In the current study we demonstrate a method of preparation of low-density polydimethylsiloxane (PDMS) foams from emulsions by using water-based thixotropic fluids as porogens. Aqueous dispersions of synthetic hectorite clay and nanocellulose were used as thixotropic fluids, enabling the preparation of fine emulsions in bulk form with the droplet size down to few tens of microns by simple hand mixing. Contrary to conventional emulsion templating where stabilization of emulsion is required, a strategy was developed for obtaining foams by using controlled destabilization of an emulsion, induced during the curing of the PDMS matrix phase by adding a carefully selected surfactant in optimized concentration.

Deposition of low-density thick silica films from burning sol-gel derived alcogels.

In the current study we show that the combustion of sol-gel derived alcogels with specifically tailored composition leads to the release of silica nanoparticles from the burning alcogel in a controlled manner which enables direct deposition of the released nanoparticles into low-density silica thick films. The process has some similarities to flame spray pyrolysis but requires no aerosol generator or other sophisticated instrumental setup. By the proper choice of catalysts and mixture of silicon alkoxides for the synthesis of the alcogel, preferential hydrolysis and polycondensation of one of the alkoxides is achieved.

Fabrication of Gelatin-ZnO Nanofibers for Antibacterial Applications.

In this study, GNF@ZnO composites (gelatin nanofibers (GNF) with zinc oxide (ZnO) nanoparticles (NPs)) as a novel antibacterial agent were obtained using a wet chemistry approach. The physicochemical characterization of ZnO nanoparticles (NPs) and GNF@ZnO composites, as well as the evaluation of their antibacterial activity toward Gram-positive ( and ) and Gram-negative ( and ) bacteria were performed. ZnO NPs were synthesized using a facile sol-gel approach.

The alterations in the extracellular matrix composition guide the repair of damaged liver tissue.

While the cellular mechanisms of liver regeneration have been thoroughly studied, the role of extracellular matrix (ECM) in liver regeneration is still poorly understood. We utilized a proteomics-based approach to identify the shifts in ECM composition after CCl4 or DDC treatment and studied their effect on the proliferation of liver cells by combining biophysical and cell culture methods. We identified notable alterations in the ECM structural components (eg collagens I, IV, V, fibronectin, elastin) as well as in non-structural proteins (eg olfactomedin-4, thrombospondin-4, armadillo repeat-containing x-linked protein 2 (Armcx2)).

Effect of glucose content on thermally cross-linked fibrous gelatin scaffolds for tissue engineering.

Thermally cross-linked glucose-containing electrospun gelatin meshes were studied as possible cell substrate materials. FTIR analysis was used to study the effect of glucose on cross-linking reactions. It was found that the presence of glucose increases the extent of cross-linking of fibrous gelatin scaffolds, which in return determines scaffold properties and their usability in tissue engineering applications.

Fibroblast growth on micro- and nanopatterned surfaces prepared by a novel sol-gel phase separation method.

Physical characteristics of the growth substrate including nano- and microstructure play crucial role in determining the behaviour of the cells in a given biological context. To test the effect of varying the supporting surface structure on cell growth we applied a novel sol-gel phase separation-based method to prepare micro- and nanopatterned surfaces with round surface structure features. Variation in the size of structural elements was achieved by solvent variation and adjustment of sol concentration.