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Updated: Jul 6, 2026
07:12
Spatio-Temporal In Vivo Imaging of Ocular Drug Delivery Systems using Fiberoptic Confocal Laser Microendoscopy
Published on: September 27, 2021
Biodegradable fumarate-based drug-delivery systems for ophthalmic applications
M C Hacker1, A Haesslein, H Ueda
1Department of Bioengineering, Rice University, MS-142, P.O. Box 1892, Houston, Texas 77251-1892, USA.
Journal of Biomedical Materials Research. Part A
|April 4, 2008
Summary
New poly(propylene fumarate)/poly(N-vinyl pyrrolidone) matrices offer sustained ophthalmic drug delivery. These photocrosslinked carriers provide long-term release of acetazolamide, dichlorphenamide, and timolol maleate for over 200 days.
Area of Science:
- Biomaterials Science
- Polymer Chemistry
- Ophthalmic Drug Delivery
Background:
- Sustained drug release is crucial for effective ophthalmic treatments.
- Poly(propylene fumarate) (PPF) and poly(N-vinyl pyrrolidone) (PVP) are potential candidates for drug delivery matrices.
- Understanding drug diffusion and release kinetics is essential for optimizing delivery systems.
Purpose of the Study:
- To investigate the function of photocrosslinked PPF/PVP matrices for sustained release of ophthalmic drugs.
- To evaluate the release kinetics of acetazolamide (AZ), dichlorphenamide (DP), and timolol maleate (TM).
- To assess the biocompatibility and potential of these matrices for long-term ophthalmic drug delivery.
Main Methods:
- Fabrication of drug-loaded cylindrical PPF/PVP rods via photoinduced cross-copolymerization.
- Quantification of drug release using high-performance liquid chromatography (HPLC).
- Analysis of release kinetics, matrix water content, degradation, and structural changes using gravimetry and microcomputed tomography.
Main Results:
- Sustained in vitro release of AZ, DP, and TM over approximately 210, 270, and 250 days, respectively.
- Dual modality release (diffusion and bulk erosion) observed after an initial burst release (<10%).
- Preliminary rabbit studies showed promising ocular biocompatibility of drug-free PPF/PVP matrices.
Conclusions:
- Photocrosslinked PPF/PVP matrices demonstrate potential for long-term ophthalmic drug delivery.
- Release kinetics are influenced by drug properties and matrix loading.
- These matrices offer a promising platform for sustained delivery of various ophthalmic medications.
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