New Materials, Compounds and Applications

Currently, nanopharmacology employs various approaches such as nanoparticles, nanocapsules, nanoemulsions and supramolecular complexes to improve drug solubility and bioavailability. Glycyrrhizic acid (GA), a natural triterpenoid from Glycyrrhiza glabra L., exhibits broad biological activities and due to its amphiphilic nature, can self-assemble into supramolecular structures. This property makes GA and its derivatives useful carriers for poorly soluble drugs. In this study, rutin, a flavonoid from Sophora japonica L., was selected to form complexes with GA and its monoammonium salt (MASGA) at molar ratios of 2:1, 4:1 and 9:1. The complexes were obtained by solvent evaporation and lyophilization and their structures were analyzed by UV and IR spectroscopy. Spectral shifts indicated hydrogen bonding and π→π* interactions between rutin and GA/MASGA molecules. Biological evaluation in mice demonstrated that the complexes significantly enhanced capillary-protective activity compared with free rutin. Among the tested systems, the GA:Rutin complex at 4:1 ratio showed the highest activity, providing a three-fold reduction in vascular permeability at a dose of 5 mg/kg, while requiring twelve times less rutin than the free compound. These findings suggest that GA-based supramolecular complexes are effective carriers for rutin and the GA:Rutin (4:1) formulation represents a promising candidate for further preclinical studies.