Fabrication of architectonic nanosponges for intraocular delivery of Brinzolamide: An insight into QbD driven optimization, in vitro characterization, and pharmacodynamics.

The intricate structure of the eye poses difficulties in drug targeting, which can be surmounted with the help of nanoformulation strategies. With this view, brinzolamide nanosponges (BNS) were prepared using the emulsion solvent evaporation technique and optimized via Box-Behnken statistical design. The optimized BNS were further incorporated into a poloxamer 407 in situ gel (BNS-ISG) and evaluated. The optimized BNS showed spherical morphology, entrapment efficiency of 83.12 ± 1.2 % with particle size of 114 ± 2.32 nm and PDI of 0.11 ± 0.01. The optimized BNS-ISG exhibited a pseudoplastic behavior and depicted a gelling temperature and gelation time of 35 ± 0.5 °C and 10 ± 2 s respectively. In-vitro release and ex- vivo permeation studies of BNS-ISG demonstrated a sustained release pattern as compared to Brinzox®. Additionally, the HET-CAM and in vitro cytotoxicity studies (using SIRC cell line) ensured that the formulation was non-irritant and nontoxic for ophthalmic delivery. The in vivo pharmacodynamic study using rabbit model depicted that BNS-ISG treatment significantly lowers the intra ocular pressure for prolonged period of time when compared with Brinzox®. In conclusion, the BNS-ISG is an efficient and scalable drug delivery system with significant potential as the targeted therapy of posterior segment eye diseases.