Acyclovir-Loaded Nanoemulsions: Preparation, Characterization and Irritancy Studies for Ophthalmic Delivery

Objective: The main goal of the present work was to develop and evaluate nanoemulsions (NEs) containing acyclovir (ACV) for ophthalmic drug delivery.Method: Firstly, component screening was performed by determining ACV solubility in various oils, surfactants, and co-surfactants. Different NE formulations were developed based on pseudo-ternary phase diagrams, and physicochemical assets were evaluated. Selected formulations were subjected to the drug release efficacy, stability studies, and ex-vivo trans-corneal permeation test. The safety of NEs was investigated by the modified Draize test and hen's egg test-chorioallantoic membrane (HET-CAM).Results: Based on the solubility studies, Tween 20, Triacetin, and Tramsectol^®P were chosen to prepare NE formulations. Developed NEs showed desirable physiochemical properties, including a droplet size of less than 15 nm. Selected formulations (F1 and F2) exhibited a sustained drug release pattern compared to the control group (P < .001). ACV penetration from F1 and F2 to the excised bovine cornea was 2.85 and 2.9-fold more than the control, respectively. Furthermore, HET-CAM and modified Draize test confirmed that F1 and F2 were safe for ocular administration.Conclusion: Present investigation revealed that ACV-loaded NEs could be effective, and safe platform for ophthalmic delivery of ACV.