Moxifloxacin-gelrite In Situ ophthalmic gelling system against photodynamic therapy for treatment of bacterial corneal inflammation

Abstract

In this study, six in situ gelling formulations based on Gelrite were prepared and evaluated for the retained ophthalmic delivery of Moxifloxacin (Mox). The effectiveness of the best developed formula G5 was compared with photodynamic therapy (PDT), the recent expanding approach for the treatment of ophthalmologic disorders after the assessment of optimum photodynamic inactivation parameters that permit efficient pathogens eradication. It was found that, Staphylococcus aureus (S. aureus) (Gram-positive) was more susceptible to effective lethal photosensitization that reaches 93.5% reduction in viable count than Escherichia coli (E. coli) (Gramnegative) of 76.1% using 3 mg/mL Hematoporphyrin (HP), illuminated by 630 nm Light Emitting Diode (LED) at 9 J/cm(2) and incubated for 15 min. Following topical instillation of G5 to rabbits corneas, higher amount of Mox was retained in the aqueous humor up to 24 h with significant 6-fold increase in the C(max) and AUC((0-∞)) compared to vigamox commercial eye drops. After post corneal infection with S. aureus, both approaches were effectively treating the infection without causing ocular irritation or collateral damage to corneal tissue where G5 showed remarkable improvement after four days compared to seven days of PDT treatment.

Development of loteprednol etabonate-loaded cationic nanoemulsified in-situ ophthalmic gel for sustained delivery and enhanced ocular bioavailability

“…Ketamine hydrochloride (50 mg/kg) in combination with a relaxing agent xylazine (10 mg/kg) was used intramuscularly to anesthetize the rabbits (El-Laithy et al, 2011). 0.1 ml of aqueous humor samples was withdrawn at the time interval of 0.25, 0.5, 1, 1.5, 4, 8 and 10 h post instillation after giving local anesthetics Benoxinate HCl (0.4%, w/v, 2 drops).…”

Positively Charged Polymeric Nanoparticle Reservoirs of Terbinafine Hydrochloride: Preclinical Implications for Controlled Drug Delivery in the Aqueous Humor of Rabbits

“…The NP suspension (F5) was instilled (50 μl) in the lower conjunctival sac of the right eye of each rabbit belonging to the first group (Treatment A) while the same volume of the oily drug solution was applied to those of the second group (Treatment B). The rabbits were systemically anaesthetized with ketamine hydrochloride (intramuscular injection, 50 mg/ kg) along with xylazine as a muscle relaxant (intramuscular injection, 10 mg/kg) (30). At 5 min intervals, the loading of formulae was performed in two instillations using a micropipette.…”

“…Care was taken to avoid touching the eye surface (8). At 0.5, 1, 2, 4, and 8 h post-instillation, the rabbits were locally anaesthetized (benoxinate HCl, 0.4% (w/v)) and aqueous humor samples (0.15 ml) were withdrawn by anterior chamber paracentesis (30)(31)(32). Following each sampling point, an ophthalmologist examined the ocular surfaces via a slit lamp to detect the presence of any damage and/or inflammation based on a scoring system ranging from (0, no inflammation to +4, and severe inflammation/damage).…”

“…The results were statistically evaluated, using one-way ANOVA, at P<0.05. The increase in the ocular drug bioavailability (folds) was estimated by dividing the AUC (0-8) of the NPs (F5) over that of the oily drug solution (30).…”

Chlorin e6 mediated photodynamic inactivation for multidrug resistant Pseudomonas aeruginosa keratitis in mice in vivo

“…However, they did not assess the impact of PDI as a single treatment. In the same year, El-Laithy et al 40. treated Staphylococcus aureus keratitis in rabbits with the photosensitizer hematoporphyrin and red light (λ = 630 nm).…”