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A Facile and Eco-friendly Route to Fabricate Poly(Lactic Acid) Scaffolds with Graded Pore Size
Published on: October 17, 2016
Synthesis and properties of poly(lactic acid).
A G Andreopoulos1, E Hatzi, M Doxastakis
1Department of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Str., 157 80 Zografou, Greece.
Journal of Materials Science. Materials in Medicine
|September 7, 2004
Summary
High molecular weight poly(D,L lactic acid) exhibits controlled degradation, suggesting its potential as a carrier for prolonged drug delivery systems.
Area of Science:
- Polymer Science
- Materials Science
- Biomaterials
Background:
- Poly(D,L lactic acid) (PDLLA) is a biodegradable polymer with potential applications in controlled release.
- Understanding the relationship between molecular weight and degradation is crucial for designing effective drug delivery systems.
Purpose of the Study:
- To synthesize PDLLA via bulk polymerization under varying pressures.
- To characterize PDLLA's properties, including molecular weight, thermal behavior, and swelling.
- To investigate the hydrolytic degradation behavior of PDLLA with different molecular weights.
Main Methods:
- Bulk polymerization of D,L-lactide under atmospheric pressure and vacuum.
- Characterization using viscosimetry (for molecular weight), differential scanning calorimetry (for thermal properties), and swelling tests.
- Hydrolytic degradation studies in buffer solutions.
Main Results:
- Amorphous PDLLA products were obtained with molecular weights ranging from 2x10^3 to 9x10^4 g/mol.
- Melting points varied between 90-210°C.
- Low molecular weight PDLLA degraded rapidly, while high molecular weight PDLLA showed a slower, potentially two-stage degradation mechanism.
Conclusions:
- PDLLA's degradation rate is dependent on its molecular weight.
- High molecular weight PDLLA demonstrates potential as a carrier for controlled release applications requiring prolonged drug delivery.
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