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Spatio-Temporal In Vivo Imaging of Ocular Drug Delivery Systems using Fiberoptic Confocal Laser Microendoscopy
Published on: September 27, 2021
Photocrosslinkable starch-based polymers for ophthalmologic drug delivery
A P Vieira1, P Ferreira, J F J Coelho
1Chemical Engineering Department, University of Coimbra, Pólo II, Rua Sílvio Lima, 3030-790 Coimbra, Portugal.
International Journal of Biological Macromolecules
|June 28, 2008
Summary
This study developed a novel starch-based polymer for controlled drug delivery. The biodegradable material shows promise for biomedical applications, offering tunable properties for drug release.
Area of Science:
- Biomaterials Science
- Polymer Chemistry
- Drug Delivery Systems
Background:
- Controlled drug delivery systems are crucial for enhancing therapeutic efficacy and patient compliance.
- Biocompatible and biodegradable polymers are highly sought after for biomedical applications.
- Starch-based materials offer a sustainable and versatile platform for developing novel biomaterials.
Purpose of the Study:
- To develop and characterize a novel starch-based polymer with urethane linkages for controlled drug delivery.
- To evaluate the physicochemical properties and in vitro degradation of the synthesized polymer.
- To assess the potential of the polymer for immobilizing and releasing model drugs.
Main Methods:
- Starch modification using 2-isocyanatoethyl methacrylate.
- Film formation via UV irradiation with Irgacure 2959 photoinitiator.
- Characterization using ATR-FTIR, swelling tests, water contact angle measurements, and SEM.
- In vitro biodegradation studies in artificial lachrymal fluid with lysozyme.
- Drug immobilization (Timolol maleate, sodium flurbiprofen) and spectroscopic release profile analysis.
Main Results:
- Successful synthesis of a starch-based polymer with urethane linkages and carbon-carbon double bonds.
- Characterization confirmed polymer structure and demonstrated tunable swelling properties in artificial lachrymal fluid at different temperatures.
- SEM revealed distinct material morphologies before and after biodegradation.
- The polymer exhibited in vitro biodegradation in the presence of lysozyme.
- Successful immobilization and controlled release of Timolol maleate and sodium flurbiprofen were observed.
Conclusions:
- The developed starch-based polymer is a promising candidate for controlled drug delivery applications.
- The material's tunable physicochemical properties and biodegradability support its use in biomedical devices.
- Further research can optimize drug loading and release kinetics for specific therapeutic needs.
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