Abstract: Device for the production of nanofibrous and/or microfibrous layers having an increased thickness uniformity by spinning a liquid material (3), said device comprising: a collecting electrode (6), a spinning nozzle (1) for dispensing the liquid material (3) to be spun, an assembly for guiding the collecting electrode (6) and/or for guiding a base strip (5) along the collecting electrode (6) or adjacent to it, such that—in the area faced by the outlet orifice (10) of the spinning nozzle (1)—the collecting electrode (6) and/or the base strip (5) move(s) in the direction (MD) spaced from the outlet orifice (10) of the spinning nozzle (1), a power supply for generating a voltage of 10 to 150 kV between the collecting electrode (6) and the spinning nozzle (1), at least one body (2), which moves along the liquid surface to destabilize the locations of the points where fibres (4) are formed on the surface of the liquid material (3) at the outlet orifice (10) of the spinning nozzle (1).

Abstract: The invention discloses a method of preparation of crosslinked materials based on polysaccharides using electromagnetic radiation in an aqueous solution containing a polysaccharide with a bound carbamate photoremovable protecting group (PPG with group —NH—CO—O—) and a polysaccharide containing an aldehyde group —CHO. The crosslinking process itself is carried out by means of a condensation reaction of the photochemically released amino group (—NH2) with the aldehyde group (—CHO) forming a bond of imine type (—N?CH—). Both processes proceed simultaneously and they can be performed under physiological conditions. The advantage of the suggested solution is the temporal and spatial control of crosslinking that allows the preparation of advanced materials for tissue engineering where the crosslink density and thus the mechanical properties in the material structure can be tailored.

Abstract: The invention relates to a self-supporting, biodegradable film comprising a C10-C22-acylated derivative of hyaluronic acid according to the general formula (I), where R is H+ or Na+, and where R1 is H or —C(?O)CxHy, where x is an integer within the range from 9 to 21 and y is an integer within the range from 11 to 43 and CxHy is a linear or branched, saturated or unsaturated C9-C21 chain, wherein in at least one repeating unit one or more of R1 is —C(?O)CxHy and where n is within the range from 12 to 4000; a method of preparation thereof and use thereof.

Abstract: The invention relates to an antitumor composition based on hydrophobized hyaluronan and inorganic nanoparticles stabilized by oleic acid. The hydrophobized hyaluronan in the form of an acylated hyaluronan serves in the composition as a carrier of inorganic nanoparticles. Out of the group of inorganic nanoparticles, the composition may comprise superparamagnetic nanoparticles, nanoparticles of ZnO and moreover, upconversion nanoparticles. Said composition is selectively cytotoxic with respect to both suspension and adherent tumor cell lines, especially with respect to tumor cell lines of colorectum carcinoma and adenocarcinoma, lung carcinoma, hepatocellular carcinoma and breast adenocarcinoma. The highest cytotoxic effects were observed in case of the composition based on an oleyl derivative of hyaluronan with SPIONs. The composition of acylated hyaluronan with SPIONs may also be advantageously used for an in vivo detection of accumulation of the composition in the body, preferably in a tumor or in liver.

Abstract: The invention relates to the preparation of new polysaccharide derivatives comprising a double bond in the positions 4 and 5 of the pyranose cycle. The method of preparation consists in the oxidation of OH group in the position 6 to an aldehyde, followed by the elimination to form a double —C?C— bond in the positions 4 and 5, and the final reduction of the aldehyde group in the position 6 into the original alcohol. The derivatives of polysaccharides prepared according to the invention show an enhanced antioxidant activity and some of them also a selective negative influence on carcinoma cell viability. (formula) where R represents —NH—CO—CH3 or —OH.

Abstract: The invention relates to the preparation and the use of ?,?-unsaturated aldehydes in the structure of sulfated polysaccharides. It concerns the derivatives with a conjugated double bond in the 4th and 5th positions of the galactopyranose part situated in the 6th position with respect to the aldehyde, according to the general structural formula (I) or its hydrated form according to the general structural formula (II). The preparation of these derivatives derives from sulfated polysaccharides containing a galactopyranose ring sulfated in the 4th position that is bound in the polymer chain via ?(1?3) or ?(1?3) O-glycosidic bond. In the described solution, the sulfated polysaccharides undergo a regio- and chemoselective oxidation to form C6-saturated aldehyde, which, via a direct elimination of the sulfate group, provides the ?,?-unsaturated derivative according to the general formula (I) or (II).

Abstract: The invention relates to the preparation of new polysaccharide derivatives comprising a double bond in the positions 4 and 5 of the pyranose cycle. The method of preparation consists in the oxidation of OH group in the position 6 to an aldehyde, followed by the elimination to form a double —C?C— bond in the positions 4 and 5, and the fmal reduction of the aldehyde group in the position 6 into the original alcohol. The derivatives of polysaccharides prepared according to the invention show an enhanced antioxidant activity and some of them also a selective negative influence on carcinoma cell viability. (formula) where R represents —NH—CO—CH3 or —OH.

Abstract: The present invention relates to pharmaceutical compositions for the treatment or prevention of ophthalmologic diseases or disorders, wherein the pharmaceutical composition comprises a solid carrier in form of a non-woven or woven made of water-soluble fibers and at least one therapeutically active agent, wherein said solid carrier is impregnated with said at least one therapeutically active agent, wherein the solid carrier readily disintegrates upon contact with the eye. Also encompassed are such composition for use in the treatment or prevention of ophthalmologic conditions and the use of the non-wovens/wovens described herein as carriers for at least one therapeutically active agent in an ophthalmologic pharmaceutical composition.

Abstract: The invention relates to conjugates of hyaluronic acid oligomer according to the general formulae I, II III or IV, or a salt thereof, the method of preparation thereof and use thereof, where the oligomer is bonded to the respective substrate by its ending anomeric center via a bi-functional amino linker by means of an amino or imino bond. This type of conjugates allows releasing oligomers in their native form. The prepared systems exhibited an enhanced biological activity against selected lines of cancer cells.

Abstract: The invention relates to a method of preparation hydrophobized hyaluronic acid (Formula I) and further to a method of encapsulating biologically active substances into the nanomicelles of hydrophobized hyaluronan serving as carriers of biologically active hydrophobic substances. The hydrophobization of hyaluronan is carried out through an esterification reaction of hyaluronan with long-chain carboxylic acids, the latter being activated by a halogenide derivative of 2,4,6-trichlorobenzoic acid or by another organic chloride. In an aqueous environment, water-soluble hydrophobized derivatives can form nanomicelles in which nonpolar substances can be bound by means of non-covalent physical interactions. The core of a nanomicelle is formed by hydrophobic acyl functional groups while the shell of a nanomicelle is formed by hyaluronic acid. The encapsulation of the substances into nanomicelles can be performed by means of the solvent exchange method or by means of sonication.