Ophthalmic-targeted brinzolamide-laden cubosomal solid lipid nano-vesicular system (Cube-SLNV): design, development, and in vitro and ex vivo characterization.

A better functional and site-specific drug delivery system for ophthalmic disease is necessary for the treatment of glaucoma. The present study aimed to design a brinzolamide (BRZ)-loaded cubosomal solid lipid nano-vesicular system (Cube-SLNV) that accomplished advanced statistical tools. Another objective was to overcome the problem of burst release associated with Glyceryl monooleate (GMO) Cube-SLNV by incorporating Gelucire 43/01 (GC43/01). The emulsification method was used to synthesize BRZ Cube-SLNV. The Plackett-Burman design (PBD) was utilized to screen the critical material (CMAs) and process attributes (CPPs). The optimization of the Cube-SLNV was accomplished through Box-Behnken design (BBD). Multivariate tools were applied to estimate the correlation between screened CMAs and critical quality attributes (CQAs). The Cube-SLNV was characterized by size, its size distribution, stability, thermal behavior, chemical interactions, BRZ release, entrapment efficiency, pH, sterility testing, and ex vivo irritation study. GMO and GC43/01 were chosen as solid lipids, whereas Poloxamer 407 (PLX) was a stabilizer for Cube-SLNV in preliminary trials. PBD-the Pareto chart suggested the significant influence of the amount of GMO, GC43/01, and PLX on the performance of Cube-SLNV, so chosen as CMAs for further optimization. BBD identified a crucial relationship between chosen CMAs and CQAs - Cube-SLNV size, poly-dispersibility index (PDI), and BRZ release. The optimized Cube-SLNV size was determined to be 101.2 nm, with a zeta potential of - 34.6 mV, a PDI of 0.253, and more than 90% entrapment efficiency. Cube-SLNV can release more than 90% BRZ within 8 h. DSC and FTIR confirmed the formation of Cube-SLNV-loaded BRZ. HATCAM study revealed that the formulation has no irritancy. The controlled release behavior from optimized BRZ with higher entrapment efficiency was observed. Cube-SLNV was developed with the amalgamation of PBD for screening and BBD for correlating CMAs and CQAs. This novel delivery system is a revitalized formulation that promises to give a potential molecule a new lease of life.