Hydrophilic polymeric nanoparticles prepared from Delonix galactomannan with low cytotoxicity for ocular drug delivery.

Delonix is a galactomannan polysaccharide extracted from the endosperm of Delonix regia plant. This study aims at the development of Delonix nanoparticle and assesses its potential for ocular delivery by evaluating its in-vitro stability, toxicity and cellular uptake. Fluorescent nanoparticles (BODIPY-loaded nanoparticles) were prepared by a Quality-by-Design modified nanoprecipitation technique. Optimized nanoparticles had mean sizes <240nm, PdI<0.2 and zeta potential of <-30mV. Mixture of surfactants with different hydrophilic-lipophilic balance controlled nanoparticle swelling. Nanoparticles, which were stable in the presence of simulated lachrymal fluid and lysozyme also sustained the release of BODIPY. In-vitro studies suggest no toxicity of the nanoparticles in concentration range of 100-1483.3µg/mL on retinal and corneal epithelial cells. Flow cytometry and confocal microscopy techniques showed that retinal cells but not corneal cells, uptake 18% of the nanoparticles. Therefore, Delonix nanoparticles could be a safe and promising tool for ocular drug delivery.