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Published on: December 27, 2013
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Drug release from PLGA microparticles can be slowed down by a surrounding hydrogel
L A Lefol1, P Bawuah2, J A Zeitler2
1Univ. Lille, Inserm, CHU Lille, U1008, Lille F-59000, France.
International Journal of Pharmaceutics: X
|December 26, 2023
Summary
Drug release from poly(lactic-co-glycolic acid) (PLGA) microparticles is significantly slower when encapsulated in a hydrogel. The hydrogel barrier hinders swelling and drug diffusion, extending release times for ibuprofen.
Area of Science:
- Biomaterials Science
- Drug Delivery Systems
- Polymer Chemistry
Background:
- Poly(lactic-co-glycolic acid) (PLGA) microparticles are widely used for controlled drug delivery.
- Understanding factors influencing drug release kinetics is crucial for optimizing therapeutic efficacy.
- Hydrogels can serve as tissue mimics, potentially altering drug release profiles.
Purpose of the Study:
- To investigate the effect of a surrounding hydrogel on ibuprofen release from PLGA microparticles.
- To elucidate the mechanisms behind altered drug release in the presence of a hydrogel.
- To compare drug release in a hydrogel environment versus agitated buffer.
Main Methods:
- Preparation of ibuprofen-loaded PLGA microparticles using emulsion solvent extraction/evaporation.
- Characterization of microparticle morphology and microstructure using optical microscopy, SEM, DSC, XRD, and X-ray μCT.
- Measurement of ibuprofen release kinetics in agarose hydrogel and agitated phosphate buffer (pH 7.4).
Main Results:
- PLGA microparticles exhibited a smooth surface and an internal porous network.
- Ibuprofen release was significantly slower in agarose gel (two weeks for complete release) compared to agitated buffer (a few days).
- Hydrogel presence likely hindered particle swelling and convective flow-induced damage, slowing drug diffusion.
Conclusions:
- Surrounding hydrogels can substantially reduce the rate of drug release from PLGA microparticles.
- The steric hindrance and reduced swelling caused by the hydrogel are key factors in slowing drug mobility.
- This finding has implications for designing drug delivery systems intended for specific tissue environments.
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