Ocular polymeric nanomicelles for the posterior eye segment in the management of retinoblastoma: formulation, optimization, <i>in vitro</i> and <i>ex vivo</i> evaluations

The existing study focuses on the development, optimization, and evaluation of sorafenib-loaded polymeric nanomicelles for posterior segment delivery in treating retinoblastoma. The formulation involved adjusting various process and product parameters to create effective drug-loaded polymeric nanomicelles. The particle size, PDI, and zeta potential of optimized formulation were found to be 65.52 ± 1.18 nm, 0.14 ± 0.01, and −3.26 ± 0.66 mV, respectively. The entrapment efficiency and drug release were estimated to be 98.84% ± 0.001 and 99.99% in 6 h, respectively. Additionally, the optimized formulation demonstrated acceptable outcomes for solid-state analysis, osmolality, pH, residual solvent, and morphological properties. After 8 h, the <i>ex vivo</i> transcleral permeation and scleral deposition were 629.05 ± 124.11 ng/cm² and 4.10 ± 0.54 µg, respectively. Y-79 (human retinoblastoma) cell line study using standard drug, test drug, and optimized formulation revealed anticancer potential at all time points (6, 12, 18, and 24 h) with comparable IC50 values. Furthermore, the optimized formulation exhibited no toxicity on the ARPE-19 (human retinal pigmented epithelium) cell line over 24 h. The optimized formulation was non-irritating to the eye (HET-CAM) and remained stable for 6 months. Thus, drug delivery to the posterior eye segment for the treatment of retinoblastoma appears to be possible with the help of established technology.