Delivery of Hydrophobic Drugs to the Posterior Ocular Region by Gel-in-Water Nanoemulsion

Abstract

Purpose The aim of this study was to develop a nanogel emulsion as a minimally invasive, safe, and effective treatment alternative for posterior ocular diseases. Methods A gel-in-water (G/W) nanoemulsion was developed by ultrasonication using beeswax as an organogelator. Different physicochemical properties were evaluated along with particle size analysis by dynamic light scattering. In vitro biocompatibility of G/W nanoemulsion using rat hepatocytes and human umbilical vein endothelial cells (HUVECs) and in vivo corneal permeability as eye drops were investigated. Results The nanogel emulsion was monodispersed with a polydispersity index and particle diameter of approximately 0.2 and 200 nm, respectively. The zeta potential value of −8.1 mV suggested enhanced stability and improved retinal permeability of nanoparticles. The prepared nanoemulsion was found to be biocompatible with hepatocytes and HUVECs in vitro. Moreover, in vivo study demonstrated high permeability of G/W nanoemulsion to the retinal layer with no ocular irritation. Conclusions G/W nanoemulsions have the potential for topical drug delivery in the posterior eye segment with maximum therapeutic efficacy. Translational Relevance Organogel nanodispersion is a new concept to deliver hydrophobic drugs to the posterior segment of eyes as a novel drug delivery system.

Recent Advances in Nanomedicine for Ocular Fundus Neovascularization Disease Management

“…It effectively delivers hydrophobic drugs to the fundus, which allows for a single administration, eliminating the need for repeated injections that can cause tissue damage and enhancing patient compliance. [156] Another example is a composite nanoemulsion for the treatment of AMD, including the combination of lutein (an antioxidant agent), stearyl penetration (a cell-penetrating agent), a nanoemulsion (a water-soluble enhancer), and gellan gum (an in situ gelling agent), which can safeguard retinal cells against the damage resulting from hydrogen peroxide (H 2 O 2 ) and scavenge intracellular ROS. [157] Furthermore, for rational drug combination and sustained retinal drug delivery, Su et al have successfully created Bor/RB-M@TRG, an intravitreal-injectable nanoemulsion depot designed for efficient permeation into the posterior ocular segment and prolonged distribution in the RPE layer for at least 14 days (Figure 7c).…”

Overview of Recent Advances in Nano-Based Ocular Drug Delivery

“…In vitro testing demonstrated the biocompatibility of the G/W NE. Meanwhile, in vivo, application as eye drops revealed no signs of ocular irritation [99]. Despite the growing literature and products in this field, there are still challenges with NEs, including the need for significant amounts of surfactants and concerns about their potential toxicity, limited capacity to solubilize high-melting-point substances, and susceptibility to environmental factors affecting stability.…”