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Spatio-Temporal In Vivo Imaging of Ocular Drug Delivery Systems using Fiberoptic Confocal Laser Microendoscopy
Published on: September 27, 2021
Injectable, in situ forming poly(propylene fumarate)-based ocular drug delivery systems.
H Ueda1, M C Hacker, A Haesslein
1Department of Bioengineering, Rice University, Houston, Texas 77251-1892, USA.
Journal of Biomedical Materials Research. Part A
|May 22, 2007
Summary
This study developed an injectable poly(propylene fumarate) (PPF) matrix for sustained ocular delivery of fluocinolone acetonide (FA). The formulation enables long-term, controlled intraocular drug release for up to 400 days.
Area of Science:
- Biomaterials Science
- Ophthalmology
- Drug Delivery Systems
Background:
- Long-term ocular drug delivery is challenging due to rapid clearance and systemic side effects.
- Biodegradable polymers offer potential for sustained intraocular drug release.
Purpose of the Study:
- To develop an injectable, in situ forming poly(propylene fumarate) (PPF) matrix for long-term ocular delivery of fluocinolone acetonide (FA).
Main Methods:
- Fluocinolone acetonide (FA) and PPF were dissolved in N-methyl-2-pyrrolidone (NMP) to form an injectable solution.
- In situ matrix formation was achieved via NMP diffusion in aqueous media.
- In vitro release studies were conducted in PBS at 37°C, analyzing FA release using HPLC.
- Investigated effects of drug loading, PPF content, and photo-crosslinking on release kinetics.
Main Results:
- Achieved drug loadings up to 5% with sustained FA release for up to 400 days.
- Observed an initial burst release (22-68%) followed by controlled release via diffusion and bulk erosion.
- Demonstrated therapeutic drug release rates dependent on formulation parameters.
Conclusions:
- Injectable, in situ formed PPF matrices are promising for long-term, controlled intraocular drug delivery.
- The formulation offers a viable strategy for sustained delivery of anti-inflammatory drugs like FA.
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