Formulation, Scaled & Controlled Engineering of Fibrous Dosage Technologies for Ocular Drug Delivery

Although directly accessible, the eye presents a plethora of complex static, dynamic and metabolic barriers which significantly hinder efficient ocular drug delivery. The use of conventional formulations e.g. eyedrops, although widely used, are limited in their retention time and poor bioavailability with less than 5% of the administered dose reaching intraocular tissues. As a result, systemic administration is often employed but there is an increased risk of toxicity associated with this. It is vital to address these limitations, given the projected global rise in age-related ocular diseases such as glaucoma and age-related macular degeneration both of which are leading causes of irreversible vision loss. With over 70 million adults expected to be affected by posterior segment diseases in the coming decades, there is a dire need for advancements in drug delivery strategies which enhance bioavailability, prolong residence time and overcome ocular barriers to enable effective, targeted treatment. Electrohydrodynamic atomisation was used to allow for the controlled engineering of fibrous dosage technologies for ocular drug delivery. A novel custom-built collection chamber was introduced to circumvent the impact of environmental parameters on the EHDA process. When used, environmental conditions were stabilised and as a result denser, more controlled spray patterns were obtained in comparison to those produced in open lab conditions thus highlighting the importance of environmental control in the enhancement of the EHDA process. Electrospinning, a brand of EHDA technologies, was explored for the fabrication of drug loaded nanofibers for sustained ocular drug delivery targeting treatments for AMD and glaucoma. Process optimisation of flow rate, applied voltage and collection distance enabled the successful encapsulation of pilocarpine HCl into PLGA nanofibers and ovalbumin into PVP nanofibers highlighting the platforms potential in the fabrication of controlled, biodegradable ocular drug delivery systems. Novel multilayered polymeric drug delivery systems were fabricated by combining solvent casted PLGA and PVP matrices with an electrosprayed coating within a novel collection chamber. Effective drug encapsulation was observed and several formulations achieved desirable release patterns suitable for ocular application.

Name dc:type.qualificationname

PhD

Level dc:type.qualificationlevel

Doctoral

Grantor dc:publisher.institution

De Montfort University

Year dc:date.issued

2025

Author dc:creator

• Zaman, Mohammed

Licence

• https://dora.dmu.ac.uk/bitstreams/46dd0966-cde2-463b-aa56-7fd1f5bf61cc/download