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Sustained Administration of β-cell Mitogens to Intact Mouse Islets Ex Vivo Using Biodegradable Poly(lactic-co-glycolic acid) Microspheres
Published on: November 5, 2016
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Risperidone Controlled Release Microspheres Based on Poly(Lactic Acid)-Poly(Propylene Adipate) Novel Polymer Blends
Stavroula Nanaki1, Panagiotis Barmpalexis2, Alexandros Iatrou3
1Laboratory of Polymer Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece. sgnanaki@chem.auth.gr.
Pharmaceutics
|August 15, 2018
Summary
This study developed novel biodegradable microspheres for controlled release risperidone injections. These poly(lactic acid)⁻poly(propylene adipate) (PLA/PPAd) blends offer promising long-acting injectable formulations.
Area of Science:
- Polymer Science and Engineering
- Pharmaceutical Technology
- Biomaterials Science
Background:
- Biodegradable and biocompatible polymers are crucial for developing effective long-acting injectable drug delivery systems.
- Poly(lactic acid) (PLA) and poly(propylene adipate) (PPAd) are promising candidates for such applications due to their tunable degradation properties.
- Risperidone is an antipsychotic medication often requiring long-acting injectable formulations for improved patient compliance.
Purpose of the Study:
- To prepare and characterize risperidone-loaded microspheres using novel biodegradable PLA/PPAd polymer blends.
- To evaluate the potential of these microspheres as long-acting injectable formulations for risperidone.
- To investigate the influence of polymer blend composition on drug release kinetics.
Main Methods:
- Synthesis and characterization of PPAd via melt polycondensation, including 1H-NMR, DSC, and XRD.
- Preparation of PLA/PPAd blends using the solvent evaporation method.
- Fabrication of risperidone-loaded microspheres using the oil-water emulsification/solvent evaporation technique.
- Characterization of microspheres using DSC, XRD, FTIR, and particle size analysis.
- In vitro drug release studies and statistical moment analysis of release kinetics.
Main Results:
- PLA/PPAd blends were found to be immiscible, with PPAd exhibiting faster enzymatic hydrolysis than PLA.
- Risperidone-loaded microspheres exhibited smooth spherical morphology with particle sizes ranging from 1 to 15 μm.
- The active pharmaceutical ingredient (risperidone) was dispersed in an amorphous state within the polymer matrices.
- All PLA/PPAd formulations demonstrated controlled in vitro release of risperidone.
- Polyester hydrolysis significantly impacted drug release, with diffusion being the primary release mechanism in high PLA content blends.
Conclusions:
- Novel biodegradable PLA/PPAd polymer blends are suitable for developing risperidone-controlled release microspheres.
- These microspheres show potential as effective long-acting injectable formulations.
- The drug release profile can be modulated by adjusting the PLA/PPAd blend ratio, offering tunable drug delivery.
Keywords:
controlled releaselong-acting injectablemicrospherespoly(lactic acid)poly(propylene adipate)polyester blendsrisperidoneMore Related Videos
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