| Popis: |
Cyclodextrins are cyclic oligosaccharides linked by α-1,4-glycosidic bonds. Among the natural cyclodextrins there are α-, β- and γ-cyclodextrins. By introducing various functional groups into the cyclodextrin ring, derivatives can be formed in order to improve their physicochemical properties. Due to the hydrophilic outer surface, the CDs are well soluble in water, while the inner space is hydrophobic and may contain another hydrophobic substance. Thanks to their various properties, they are used in various industries. Cyclodextrins are widely used in the pharmaceutical, cosmetic and food industries. The physicochemical properties of the free drug as well as the free cyclodextrin differ from the properties of the prepared inclusion complex. They increase the stability and solubility of poorly soluble substances in water. They reduce the unpleasant, bitter taste of substances such as diltiazem or ranitidine. Moreover, they may increase the thermal stability of drugs. In complexes with antibiotics, they can increase their antibacterial activity. In cosmetics, cyclodextrins are often used to eliminate odor, minimize skin irritation, and improve the solubility and stability of the active ingredient. Cyclodextrins also have the ability to form complexes with cholesterol or pesticides, which allows the production of products with a reduced cholesterol content and a positive impact on the environment. This article presents several typical methods of complexation with cyclodextrins, their potential influence on the change of physicochemical properties of compounds, and some techniques used in terms of examination of their structure, interaction, stability or solubility. Nowadays, it has been observed that research groups focused on analyze the structure, interaction, stability in various environmental conditions (including photostability) and solubility of combinations active substances with cyclodextrins. The work also concentrates on various analytical techniques that are used in the research of complexes of cyclodextrins with ingredients of medicinal products, food and cosmetics. |
