Self-Assembled Supramolecular Hydrogel Based on alpha-Cyclodextrin/Poloxamer Polypseudorotaxanes for Ocular Delivery of Ciprofloxacin

Background and Objectives: Ciprofloxacin (CIP) is a fluoroquinolone antibiotic used for the management of eye bacterial infections. To overcome the challenges like poor ocular residence time and poor bioavailability, this study aimed at formulating and optimizing ciprofloxacin Self-assembled supramolecular hydrogel based on alpha-cyclodextrin/Poloxamer polypseudorotaxanes to enhance the ocular availability of the drug. Materials and Methods: A Box-Behnken experimental design with three formulation factors including the concentration of poloxamer, cyclodextrin and their ratio were studied using Design-Expert software. In vitro permeation, ex vivo permeation, anti-bacterial studies and in vivo of precorneal concentration of drug was determined. Results: Both the viscosity and drug release were found to be dependent on poloxamer and cyclodextrin concentrations, while PLX:CD ratio was found to have a significant effect on the viscosity only. The optimized system with maximized viscosity and drug release exhibited a higher CIP permeation compared to conventional Carbopol (R) gel. The antibacterial studies with various bacterial strains indicated a significant improvement in the antibacterial activity of CIP when presented in the optimized formulation. Further, a higher amount of CIP was retained in the precorneal area for a prolonged period following the instillation of supramolecular gel as compared to the conventional gel. Conclusion: Overall, the proposed supramolecular gel could be regarded as an effective platform for improving the ocular retention and availability of ciprofloxacin. Further studies and clinical trials would help to explore this formulation for therapeutic use.