Development of ganciclovir/resveratrol coloaded bilosomes for improvement of ophthalmic delivery and therapeutic efficacy

Bilosomes have been investigated as potential carrier for ocular delivery. Ocular viral infection may lead to direct or autoimmune damages, uveoretinitis, and disturbed vision. In this work, we fabricated ganciclovir (antiviral agent) and resveratrol (natural antioxidant and anti-inflammatory) coloaded bilosomes. The influence of bile salt concentration and chitosan coating was investigated. Formulations were subjected to physicochemical characterizations and the selected formulations were assessed for structural analyses, <i>in vitro</i> release, <i>ex vivo</i> corneal permeation, and <i>in vivo</i> appraisal. Increasing bile salt concentration resulted in an increase in particle diameter and zeta-potential negativity, while chitosan coating increased vesicular size and shifted the zeta potential to positive values. F3 (containing 10 mg/mL sodium taurocholate) and F4 (chitosan coated F3) showed satisfying results of physicochemical characteristics. Structural analyses proved that lipophilic resveratrol was located in lipid bilayer while hydrophilic ganciclovir was located in aqueous core of the vesicles and both of them were in an amorphous state. F4 provided excellent ocular delivery of resveratrol and ganciclovir presented by higher transcorneal flux (3.27 ± 0.28 and 2.31 ± 0.17 μg/cm²/h, respectively) and permeability coefficient (1.64 ± 0.09 and 1.15 ± 0.08 cm²/h, respectively) when compared to F3 and drugs' suspension. Histological evaluation demonstrated that F4 surpassed F3, showing non-irritant properties and marked anti-inflammatory activity. Conclusively, these findings suggested that F4 coloaded with ganciclovir and resveratrol might be a promising strategy for the feasible treatment of ocular viral infection and its accompanying inflammatory symptoms.