Infill-Modulated, Bioerodible, and Biocompatible Ocular Inserts for Tunable Acyclovir Release via Direct Powder...

Area of Science:

• Ophthalmology
• Materials Science
• Pharmaceutical Sciences

Background:

• Conventional herpetic keratitis treatments face challenges like rapid drug elimination and poor patient adherence.
• Sustained-release ocular drug delivery systems are needed to improve therapeutic efficacy and patient compliance.

Purpose of the Study:

• To develop and characterize sustained-release, dissolvable ocular inserts for acyclovir using direct powder extrusion (DPE) 3D printing.
• To evaluate the impact of infill density on drug release kinetics, transcorneal permeation, and biocompatibility.

Main Methods:

• Fabrication of acyclovir-loaded ocular inserts via DPE 3D printing with varying infill densities (30%, 60%, 90%).
• In vitro drug release studies, transcorneal permeation assays, and biocompatibility assessments (HET-CAM, hemocompatibility, cell viability).
• Confocal laser scanning microscopy (CLSM) to evaluate drug penetration and retention in corneal layers.

Main Results:

• Lower infill density inserts showed faster erosion and higher acyclovir release (~95% in 24h) with enhanced transcorneal permeation.
• Higher infill density inserts exhibited slower release (~58% in 24h) and reduced permeation.
• All formulations demonstrated good biocompatibility, physiological pH, flexibility, and Weibull release kinetics, with 3D-printed inserts showing significantly enhanced corneal penetration and retention.

Conclusions:

• DPE 3D printing is a viable method for creating customizable, bioerodible ocular inserts for sustained drug delivery.
• These inserts offer potential for improved treatment of herpetic keratitis through tailored release, enhanced corneal retention, and better patient compliance.