Related Experiment Video
Updated: Mar 17, 2026

Ocular Therapeutic Delivery and Advanced Tissue Retrieval in Adult Rats
Published on: May 23, 2025
Exploring the Effect of Surface Hydrophilicity of Nanoparticles on Ocular Posterior Transport Pathway via
Yidan Wei1, Renfang Zhu1, Ying Xu1
1School of Pharmacy, Shenyang Key Laboratory of Intelligent Mucosal Drug Delivery Systems, Shenyang Pharmaceutical University, Shenyang, China.
Abstract:
Short residence time and off-target accumulation restrict ocular posterior delivery via topical administration. How to improve posterior drug delivery through non-invasive method is the issue to be addressed. Inspired by the higher posterior delivery efficiency of conjunctival-scleral pathway and hydrophilicity-related tissue preference, the objective is to verify the feasibility of altering posterior tissue distribution via conjunctival-scleral pathway by tuning nanoparticles (NPs) hydrophilicity. Herein, triamcinolone acetonide-loaded NPs with different surface hydrophilicity were prepared by mixing poly(lactide-co-glycolide) and poly(lactide-co-glycolide)-polyethylene glycol (PLGA-PEG) at different ratios. 3.5% and 16.7% PEG NPs displayed 1.5- and 1.8-fold higher sclera Papp than 0% PEG NPs. Furthermore, the higher the surface hydrophilicity, the more NPs in conjunctiva but less in cornea, 3.5% and 16.7% PEG NPs showed 1.4- and 1.8-fold higher choroid-retina distribution than 0% PEG NPs via conjunctival-scleral pathway. The higher posterior delivery was confirmed by enhanced therapeutic efficacy in vascular endothelial growth factor-induced retinal neovascularization rabbit model. After dropped twice daily for 14 days, 3.5% and 16.7% PEG NPs reached comparable therapeutic effect with intravitreal injection. This study demonstrated the significance of NPs surface hydrophilicity in posterior delivery, providing theoretical basis for rational design of NPs for ocular posterior diseases therapy by topical dropping.
More Related Videos
Related Concept Videos
Ophthalmic Drug Delivery Systems
Drug Delivery: Miscellaneous Routes
Oral inhalation and nasal sprays swiftly transfer drugs across the respiratory epithelium's mucosal layer. Inhaled glucocorticoids and bronchodilators directly target lung conditions such as asthma, while fluticasone nasal spray mitigates allergic rhinitis.
Transdermal patches transport drugs...
Factors Affecting Dissolution: Particle Size and Effective Surface Area
Indirect-Acting Cholinergic Agonists: Pharmacokinetics
Reversible agents containing quaternary amines, such as neostigmine and edrophonium, are not easily absorbed orally because they...
Drug Delivery: Overview
Enteral delivery involves administering drugs directly through swallowing, sublingual placement, or buccal application. Orally administered drugs predominantly navigate the...
Bioavailability Enhancement: Drug Permeability Enhancement

