Nanoparticles of thiolated gum ghatti for the controlled ocular delivery of Ciprofloxacin.

Abstract

Background: Conjunctivitis is the most prevalent ocular disorder and characterized by irritation, swelling and inflammation of the conjunctiva. Fluoroquinolones are the most promising classes of antibiotics and among them; ciprofloxacin (CFX) is used to treat conjunctivitis.

Objectives: To provide a controlled-release approach for extended antibacterial action, CFX-loaded thiolated gum ghatti (TGG) nanoparticles were developed to overcome the drawbacks of traditional eye medications (rapid elimination, low bioavailability).

Methods: Gum ghatti (GG) was thiolated with 3-mercaptopropionic acid (3-MPA) to enhance the mucoadhesion. The nanoprecipitation technique was applied to produce nanoparticles of TGG loaded with CFX. Particle size, zeta potential, FTIR, DSC, TGA, and XRD were employed to characterize GG, TGG, and nanoparticles. Permeation, mucoadhesion, ocular irritation and pharmacokinetics were performed.

Results: TGG and nanoparticles contained 0.09 and 0.13 mmoL of thiol groups/mg of polymer, respectively. Nanoparticles showed a diameter of < 200 nm and PDI of < 0.3, and showed improved CFX penetration by 80% compared to pure CFX. Nanoparticulate formulation showed no ocular irritation and sustained release of CFX with improved pharmacokinetic parameters.

Conclusion: Thiolation is responsible for the improved mucoadhesion of TGG (1-fold) and nanoparticle (2-fold) compared to GG, making it suitable for creating eye formulations for the treatment of bacterial infections.