OFLOXACIN ION PAIRING WITHIN SUBMICRON EMULSION: A POTENTIAL APPROACH FOR OCULAR DELIVERY

The aim of the work was to improve the entrapment of ofloxacin within the submicron emulsion by ion pairing with sodium deoxycholate to improve antimicrobial activity and precorneal retention. Partition coefficient of ofloxacin-sodium deoxycholate was found to be 3.788, compared to 0.113 for the drug alone. Formulation was characterized for globules size 0.143 ± 0.07 μm, viscosity 3.8 ± 0.2 cP and pH, 7.1 ± 0.3. The entrapment was 80 ± 1% for ofloxacin-sodium deoxycholate in submicron emulsion compared to 57 ± 2% for the drug alone. More than 90% drug remained after 90 days in optimized formulations and was found stable. SEM confirmed droplets size to be 200 nm and spherical. Drug released 53.16% after 24 h from optimized formulation. In vitro antimicrobial efficacy improved against S. aureus as compared to free drug. No toxicity of optimized formulation on HET-CAM test was observed. Designed formulation may hold some promise for severe ocular infections where frequent dosing is required.

FORMULATION AND EVALUATION OF SUBMICRON EMULSION CONTAINING ENTRAPPED FLUOROQUINOLONE FOR OCULAR DELIVERY

Objective: The objective of the present work was to develop and characterize the submicron emulsion bearing antimicrobial drug sparfloxacin for improvement of ocular activity by improved retention in eyes. The developed delivery system was results with prolonged drug release as compared to the conventional dosage form.Methods: SE prepared by high energy emulsification and sonication to obtain uniform globule size.Results: Average internal droplets size of the optimized formulation was 0.278±0.6 μm, pH of the optimized formulation was 6.9±0.6 (average of three determinations), and viscosity 2.9±0.5 cps suitable for ocular use. Entrapment of SF was 63±3.4%. Stable under accelerated and long-term at 4°C and 37°C. No major changes reported on pH and viscosity of optimized formulations. In vitro, drug release pattern showed sustain release of SF, a cumulative percent release of SF was found 87.8±1.7% within 24 h. Transmission electron microscopy showed spherical shape and size within 1 μm.Conclusion: Designed formulation can be a good candidate for ocular drug delivery for severe ocular infections where frequent dosing required for conditions such as endophthalmitis, corneal ulcer, and penetrating trauma.