Abstract
The research work was driven to develop novel nanostructured liquid crystalline particles of vancomycin for its improved pre-ocular residence time, ocular bio-availability, enhanced targeting, increased permeability, reduced dosing frequency, controlled drug release and reduced systemic side-effects. Formulation was developed by fragmenting cubic crystalline phase of glycerol monooleate, water and poloxamer 407. A four-factor, three-level Taguchi statistical experimental design was constructed to optimize the formulation. Formulations exhibited internal-cubic structure of the vesicles with particle size in the range of 51.11 ± 0.96 nm to 158.73 ± 0.46 nm and negative zeta potential. Ex-vivo transcorneal permeation studies demonstrated that the optimized cubosomes had 2.4-fold increase in apparent permeability co-efficient as compared to vancomycin solution. Whereas, in-vivo studies in rabbits demonstrated that the severity of keratitis was considerably lowered in day 3 with optimized cubosomes. Ocular pharmacokinetic studies evaluated level of drug in aqueous humor and results revealed that the time to peak concentration (Tmax) of vancomycin loaded cubosomal formulation was about 1.9-fold higher and mean residence time was 2.2-fold greater than vancomycin solution. Furthermore, histological examination revealed that the corneal layers displayed well-maintained morphology without any stromal swelling, consequently indicating safety of formulation. In conclusion, results manifested that the developed vancomycin loaded cubosomes could be a promising novel ocular carrier and an ideal substitute for conventional eye-drops for the management of bacterial-keratitis.
Quality by design (QbD) in the formulation and optimization of liquid crystalline nanoparticles (LCNPs): A risk based industrial approach