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Synthesis of Monodisperse Cylindrical Nanoparticles via Crystallization-driven Self-assembly of Biodegradable Block Copolymers
Published on: June 20, 2019
Polymer-directed crystallization of atorvastatin.
Hyemin Choi1, Hyeseung Lee, Min Kyung Lee
1Department of Chemical Engineering and Materials Science, Chung-Ang University, Seoul 156-756, Republic of Korea.
Journal of Pharmaceutical Sciences
|May 26, 2012
Summary
This study demonstrates a novel polymer-directed crystallization method for atorvastatin. This technique engineers drug crystals for improved release and stability, offering an alternative to solid dispersions.
Area of Science:
- Materials Science
- Pharmaceutical Science
- Biomaterials
Background:
- Living organisms create mineral mesocrystals using peptides and proteins.
- Polymer-directed crystallization is a biomimetic technique applied to inorganic materials but rarely to drugs.
Purpose of the Study:
- To apply polymer-directed crystallization to atorvastatin (a drug).
- To investigate the characteristics of resulting atorvastatin composite crystals.
- To evaluate the potential for engineering drug release and stability.
Main Methods:
- Atorvastatin was crystallized using various polymers (polyethylene glycol, polyacrylic acid, polyethylene imine, chitosan, hydroxypropyl cellulose) via drowning-out crystallization.
- Composite crystal formation was analyzed using X-ray diffraction.
- Drug properties including melting point, heat of fusion, stability, and in vitro release were assessed.
Main Results:
- Composite crystals with significant polymer content and unusual properties were successfully produced.
- Atorvastatin crystals with polyethylene glycol, polyacrylic acid, polyethylene imine, and chitosan exhibited reduced melting points, improved stability, and sustained release.
- Hydroxypropyl cellulose resulted in enhanced in vitro release and improved drug stability under forced degradation.
Conclusions:
- Polymer-directed crystallization is a viable method for creating novel atorvastatin mesocrystal structures.
- This technique offers a new approach to enhance drug release, stability, and processability, distinct from solid dispersion methods.
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