Chitosan Hydrogel Improves Bioavailability of Megosin

Abstract Background The aim of this study was to obtain chitosan hydrogels containing megosin, an antiviral medicinal substance, to prolong its bioavailability. Megosin as an immunomodulating agent possesses at least twice higher virostatic and virucidal activities than gossypol, the megosin precursor, and other imine derivatives of gossypol. Materials and Methods Chitosan, used in this paper, was obtained by deacetylation of chitin; megosin was obtained on the bases of gossypol. Different concentrations of sodium tripolyphosphate (STPP) were used as the cross-linking agent. The release of megosin from hydrogel samples into blood was conducted on five white rats in four groups. Results Infrared spectral data demonstrated cross-linkage that the band responsible for NH bending of the uncross-linked chitosan reduced its intensity and moved to a lower wavelength, 1636 cm−1. It has been proven that megosin contained in gels does not penetrate into the blood and organs after vaginal administration. Release kinetics of megosin from chitosan hydrogels revealed that within 7 h, up to 52% of megosin is allowed into acidic solution (pH 4.5). Conclusion This study demonstrates the possibility to prolong bioavailability of megosin for at least 7 h, during which time it is not released into blood. The obtained results show the possibility to use the gel composition to treat vaginal herpes.