This research is devoted to the development and optimization of fine purification processes realized on short monolithic columns (CIM disks), using influenza vaccine and viruslike synthetic particles as model objects. The pseudoaffinity mode of liquid chromatography has been used as a tool for dynamic adsorption experiments. Viruslike particles, close to the dimensions of influenza viruses, were developed by means of main antigen of influenza viruses (hemeagglutinin) covalent binding to the outer aminated surface of synthetic latex particles. The natural receptor analogues of sialic acid were used as affinity ligands immobilized on the surface of the CIM disk by different ways to achieve a high adsorption capacity. Also, some other ligands were tested as possible candidates for virus capturing. The affinity binding parameters for influenza A virus were obtained by frontal elution method at optimized chromatographic conditions and immobilization schemes. The experimental data pointed out the possibility of selective isolation of hemeagglutinin from a mixture of vaccine proteins. The results obtained by fast affinity chromatography have shown functional and sterical correspondence viruslike synthetic models to influenza viruses. Additionally, the optimization of chromatographic conditions allowed isolation of influenza virus A while maintaining its virulence. The maximum value of adsorption capacity was registered for a monolithic disk, modified subsequently by chitosan and 2,6-sialyllactose and found to be equal to 6.9 x 10(12) virions/mL support.

The main objective of the present paper was to test the recently developed new type of 3-D protein microarray system based on glycidyl methacrylate-co-ethylene glycol dimethacrylate (GMA-EDMA) monolithic material for efficient and fast virus detection. The large-size synthetic particles bearing adsorption-responsible biomolecules on their surface were used as a virus model. Two affinity pairs were chosen for present study. Model virus-like particles, close to the dimensions of human viruses, were developed by means of protein (one of affinity partners) covalent binding to the outer carboxylated surface of polymer latexes (polystyrene based, 80-nm diameter). Recently, it was shown that the adsorption of similar synthetic particles was defined by a protein covering the particle surface. The corresponding complement was immobilized on the surface of prepared by photoinitiated polymerization GMA-EDMA macroporous layers. The detection of a formed biocomplementary complex between protein-bearing latex particle and immobilized affinity partner was carried out by two different methods: (1) similar to an ELISA approach using horse radish peroxidase conjugated with monoclonal antibodies and (2) direct method using two markers. In parallel, the pairing of native proteins was also evaluated. The adsorption behavior of studied particles has been additionally investigated by affinity adsorption at static and dynamic (frontal elution) conditions using the same GMA-EDMA material shaped as a short monolithic column (CIM Disk, BIA Separations, Ljubljana, Slovenia). The results obtained for these virus-mimicking supramolecular structures can be further used for the construction of a rapid, highly sensitive, and highly specific test intended for precise diagnostics of some respiratory tract infection viruses.

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This paper describes the preparation of oxidized hyaluronan crosslinked gelatin microspheres for drug delivery. Microspheres were prepared by a modified water-in-oil-emulsion crosslinking method, where 3-dimensional crosslinked hydrogel microspheres formed in the absence of any extraneous crosslinker. SEM analyses of the microspheres showed rough surfaces in their dried state with an average diameter of 90 µm. Lyophilization of fully-swollen microspheres revealed a highly porous structure. Guanidinoethyl disulfide (GED) was used as a model drug for incorporation into the microspheres; encapsulation of GED was confirmed by HPLC. There was an inverse correlation between the diameters of the microspheres with their GED loading. Macrophage was used as a model cell to evaluate the in vitro efficacy of GED release from the microspheres. The in vivo efficacy of the microspheres was further validated in a mouse full-thickness transcutaneous dermal wound model through suppression of cell infiltration.

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The recent studies in nanotechnology resulted in the development of novel formulations with improved bioavailability. This is especially important for oral administered drugs as the most convenient formulations. The current review deals with the processes occurring at the gastro-intestinal (GI) tract and their influence on the drug form. The increase of bioavailability of the drug may be achieved through designing novel formulations according to the specific drug properties. They include capsules that release pharmaceutical agents at various parts of the GI tract, floating systems that prolong the presence of the drug in the GI tract, dispersed forms with surface-active soluble polymers, micelles that carry poor-soluble drugs inside their non-polar core, agents that facilitate tight junction opening, such as caprate and chitosan, and lipid-based formulations. The own data show the stimulating influence of phospholipid nanoparticles on peroral absorption of drug indomethacin in rats and on passage of transport marker and drugs through Caco-2 cell monolayer in vitro. The review summarizes current understanding of factors that influence the bioavailability of the oral drug forms, currently used models for pharmacokinetic studies, and various approaches to developing novel pharmaceutical forms that increase the bioavailability of the drugs.

Dimethylformamid (I) wird in Tetrahydrofuran in Gegenwart von Katalysatoren durch Trialkyl‐ und Alkylchlorsilane (II) zu Trimethylamin (III) reduziert.