Data · dataset · 2026
Intrascleral implants for posterior segment drug delivery
Listed in ZivaHub and Deakin Research Online and DMU Figshare — shown once because both records carry DOI 10.17034/32805866.v1
Age-related macular degeneration (AMO) and diabetic retinopathy (DR) are chronic ocular diseases that can cause vision loss, primarily affecting the elderly and diabetic populations worldwide.
Description
In these conditions, abnormal blood vessels grow at the back of the eye, damaging the posterior segment. These immature vessels leak blood into the retina, exacerbating the condition.
Clinical biomarkers for these disorders include elevated levels of inflammatory markers and growth factors like vascular endothelial growth factor (VEGF), indicating chronic inflammation and pathologic angiogenesis. <br><br>Current treatments involve frequent intravitreal injections of anti-VEGF antibodies directly into vitreous humor. While achieving high drug concentrations with fewer side effects than systemic delivery, these injections carry risks of serious eye infections, retinal detachment, and intravitreal hemorrhage. <br><br>This thesis hypothesises that episcleral and intrascleral routes offer minimally invasive methods for delivering sustained-release formulations to the posterior segment.
Read the rest (3 more)
Two novel drug delivery platforms were developed and characterized: poly (glycerol sebacate):gelatin (PGS:gelatin) electrospun inserts loaded with sunitinib, and hydroxypropyl-β-cyclodextrin (HPβCD)-based electrospun inserts loaded with fenofibrate. <br>The PGS: gelatin system was optimized for polymer ratio, with the 3:2 PGS:gelatin ratio showing the most favourable release profile over an eight-day period. Both episcleral and intrascleral applications were were investigated, with episcleral administration showing higher initial drug permeation (12.5% across sclera within 24 h) compared to intrascleral delivery (10%), while intrascleral implants provided more uniform daily drug release.
The formation of inclusion complexes between fenofibrate and HPβCD, confirmed through multiple analytical techniques, significantly enhanced drug solubility in the second system. This polymer-free electrospun system maintained therapeutic activity while improving delivery efficiency, with higher drug loadings showing more sustained release profiles.<br><br><div>In vitro biocompatibility studies on ARPE-19 cells and the Hen's egg test-chorioallantoic membrane (HET-CAM) assay demonstrated both systems' safety for ocular application, with no signs of blood vessel rupture, hemorrhage, or coagulation.
Cell viability remained above 85% across all formulations tested. Both delivery systems demonstrated significant anti-angiogenic effects in multiple models, including wound healing assays, fibrin bead assays, and Ex vivo choroidal sprouting assays. The sunitinib-loaded system showed superior performance to clinically established VEGF inhibitors in the fibrin bead assay, in ex vivo models.</div><div><br></div><div>This research demonstrates the potential of episcleral and intrascleral routes for minimally invasive depot forming drug delivery systems, offering the potential for less frequent administration in the long-term manaoement of chronic posterior seoment ocular diseases like AMO and diabetic retinopathv.</div><div><br></div><div><i>Thesis is embargoed until 31 July 2028</i>.</div>
Links
Where it is published
- DOI doi.org/10.17034/32805866.v1 ↗
DOI / persistent id · from zivahub uct ac za
Catalogue records · 1
- OAI-PMH record api.figshare.com/v2/oai?verb=GetRecord&metadataPrefix=oai_dc&identifier=oai%3Af… ↗
metadata API · from zivahub uct ac za
Topics
Provenance · 3 source records, 8 field assertions
| Source | Key | Last seen | Raw |
|---|---|---|---|
| ZivaHub | oai:figshare.com:article/32805866 | 13 d ago | JSON v1 |
| Deakin Research Online | oai:figshare.com:article/32805866 | 13 d ago | JSON v1 |
| DMU Figshare | oai:figshare.com:article/32805866 | 13 d ago | JSON v1 |
| Field | Assertion | Extractor | Evidence |
|---|---|---|---|
| access_level | source · zivahub uct ac za | connector:zivahub_uct_ac_za@1.0.0 | |
| concepts[field].local:field:earth-environmental | mapping · figshare dmu ac uk | connector:figshare_dmu_ac_uk@1.0.0 | |
| concepts[field].local:field:earth-environmental | mapping · zivahub uct ac za | connector:zivahub_uct_ac_za@1.0.0 | |
| concepts[field].local:field:earth-environmental | mapping · dro deakin edu au | connector:dro_deakin_edu_au@1.0.0 | |
| description | source · zivahub uct ac za | connector:zivahub_uct_ac_za@1.0.0 | /metadata/dc/description |
| license_text | source · zivahub uct ac za | connector:zivahub_uct_ac_za@1.0.0 | |
| publication_date | source · zivahub uct ac za | connector:zivahub_uct_ac_za@1.0.0 | |
| title | source · zivahub uct ac za | connector:zivahub_uct_ac_za@1.0.0 | /metadata/dc/title |