derivado c6-c18 acilatado de ácido hialurônico, método de preparação de um derivado de ácido hialurônico, composição nanomicelar com base em um derivado c6-c18 acilatado de ácido hialurônico, método de preparação da composição nanomicelar, uso de composição nanomicelar, método de preparação de composição nanomicelar estabilizada

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. Hyaluronic nanomicelles support the penetration of bound substances in topical applications and enable the bound substances to be transferred into the individual cells. The nanomicelles obtained from hydrophobized hyaluronan derivatives are usable in cosmetic and pharmaceutical applications.