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Simultaneous drug release at different rates from biodegradable polyurethane foams
Wesley N Sivak1, Jianying Zhang, Stephané Petoud
1Department of Bioengineering, School of Engineering, University of Pittsburgh, Pittsburgh, PA, USA.
Acta Biomaterialia
|April 29, 2009
Summary
Researchers developed degradable polyurethane foams for controlled, simultaneous release of anti-cancer drugs like doxorubicin and DB-67. Drug release rates depend on temperature and drug structure, enabling tailored therapeutic delivery.
Area of Science:
- Biomaterials Science
- Polymer Chemistry
- Drug Delivery Systems
Background:
- Polyurethane foams offer potential for controlled drug release applications.
- Simultaneous delivery of multiple therapeutic agents requires sophisticated material design.
- Covalent incorporation of drugs allows release linked to material degradation.
Purpose of the Study:
- To develop a single-phase, degradable polyurethane foam for simultaneous, differential release of multiple drugs.
- To investigate the covalent incorporation and release kinetics of anti-cancer drugs DB-67 and doxorubicin.
- To explore the influence of temperature and drug chemical structure on release rates.
Main Methods:
- Lysine diisocyanate (LDI) and glycerol were used to synthesize polyurethane foams.
- Anti-cancer drugs DB-67 and doxorubicin were covalently attached to the polyurethane matrix.
- Infrared spectroscopy and fluorescence spectroscopy were employed for reaction monitoring and drug quantification.
- Drug release profiles were assessed at various temperatures (4-70°C) over 10 weeks.
Main Results:
- DB-67 and doxorubicin formed urethane linkages with LDI.
- Foam characteristics (sol content, porosity, drug distribution) were consistent across samples.
- Drug release was temperature-dependent and varied based on the incorporated drug's chemical structure.
- Simultaneous release of both drugs from the same foam was achieved.
Conclusions:
- Degradable LDI-glycerol polyurethane foams can be engineered for simultaneous, differential drug release.
- Covalent drug incorporation enables controlled release synchronized with material degradation.
- This approach holds promise for advanced combination cancer therapy delivery systems.
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