Abstract: Microparticles based on ester derivatives of hyaluronan and related methods and compositions are disclosed. The microparticles comprise a conjugate of all-trans retinoic acid and a particular hyaluronan comprising from 1 to 5000 dimer units; where the microparticles comprise a degree of substitution of all-trans retinoic acid residues in the conjugate of hyaluronan in the range of from 0.1 to 8%. Methods of preparing the microparticles and related compositions are also disclosed.

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 present invention relates to the fluorescent conjugate of hyaluronic acid containing cypate or salts thereof, the hydrophobized conjugate, methods of the preparation and use thereof in medicinal applications for in vivo imaging and the treatment of neoplasms.

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.

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 nanofibers containing photocurable ester derivatives of hyaluronic acid or its salt, the method of preparation thereof, and the photocured preparation made from the nanofibers by light irradiation and the use thereof

Abstract: The invention relates to a new method of preparation of a hyaluronan derivative with an aldehydic group in the position (6) of the polysaccharide glucosamine part. The hyaluronic acid oxidation can be performed by means of TEMPO/NaCIO or TEMPO/TCC systems in a protic environment with or without the presence of anorganic salts. Thus prepared aldehyde can be used for binding amines, diamines, amino acids, peptides and other compounds containing an amino group, e.g. by means of the reductive amination with NaBH3CN in water or in a water-organic solvent system. When a diamine or compounds containing three or more amino groups are used, cross-linked hyaluronan derivatives can be prepared. Cross-linked derivatives can be also prepared by a reaction of the aldehyde with a hyaluronan substituted by an amino-alkyl group HA-alkyl-NH2.

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.

Abstract: The invention relates to a new method of preparation of a hyaluronan derivative with an aldehydic group in the position (6) of the polysaccharide glucosamine part. The hyaluronic acid oxidation can be performed by means of TEMPO/NaCIO or TEMPO/TCC systems in a protic environment with or without the presence of anorganic salts. Thus prepared aldehyde can be used for binding amines, diamines, amino acids, peptides and other compounds containing an amino group, e.g. by means of the reductive amination with NaBH3CN in water or in a water-organic solvent system. When a diamine or compounds containing three or more amino groups are used, cross-linked hyaluronan derivatives can be prepared. Cross-linked derivatives can be also prepared by a reaction of the aldehyde with a hyaluronan substituted by an amino-alkyl group HA-alkyl-NH2.

Abstract: The invention relates to a crosslinked hyaluronan derivative in the form of a hydrogel or microfibers, and to a method of preparation thereof, consisting in a C—C coupling reaction. The C—C coupling reaction is performed via reaction of a hyaluronan derivative carrying a terminal aryl-halide and/or aryl-borate group, and a hyaluronan derivative carrying an alkenyl or alkynyl group, in water, phosphates buffer or a mixture of an organic acid and an alcohol, and in the presence of a palladium active catalyst. The palladium active catalyst may be e.g. a complex of palladium (II) acetate and an inorganic or organic base, or a complex of palladium (II) and 2-amino-4,6-dihydroxypyrimidine.

Abstract: The present invention describes novel amphoteric materials based on crosslinked hyaluronic acid, according to the general formula (I), and a method of preparation of said materials. Further, the invention relates to the material containing entrapped active agents (e.g. drugs, growth factors etc.) and a method of preparation thereof. Moreover, the present invention relates to the use of said materials for controlled release systems, in tissue engineering, wound dressing or tissue regeneration.

Abstract: The invention relates to a new method of preparation of a hyaluronan derivative with an aldehydic group in the position (6) of the polysaccharide glucosamine part. The hyaluronic acid oxidation can be performed by means of TEMPO/NaCIO or TEMPO/TCC systems in a protic environment with or without the presence of anorganic salts. Thus prepared aldehyde can be used for binding amines, diamines, amino acids, peptides and other compounds containing an amino group, e.g. by means of the reductive amination with NaBH3CN in water or in a water-organic solvent system. When a diamine or compounds containing three or more amino groups are used, cross-linked hyaluronan derivatives can be prepared. Cross-linked derivatives can be also prepared by a reaction of the aldehyde with a hyaluronan substituted by an amino-alkyl group HA-alkyl-NH2.