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Flash NanoPrecipitation for the Encapsulation of Hydrophobic and Hydrophilic Compounds in Polymeric Nanoparticles
Published on: January 7, 2019
Supercritical antisolvent precipitation of PHBV microparticles
Mariana Sousa Costa1, Ana Rita C Duarte, M Margarida Cardoso
1REQUIMTE/CQFB, Departamento de Química, FCT-UNL, 2829, 516 Caparica, Portugal.
International Journal of Pharmaceutics
|September 15, 2006
Summary
Supercritical antisolvent (SAS) technique successfully micronized poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) into microspheres. Optimal conditions yielded 3-9 micrometer particles, with lower hydroxyvalerate content improving sphericity.
Area of Science:
- Materials Science
- Chemical Engineering
- Polymer Science
Background:
- Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is a biodegradable polymer with potential applications in various fields.
- Micronization is crucial for controlling the properties and applications of PHBV-based materials.
- Supercritical antisolvent (SAS) technology offers a promising route for polymer micronization.
Purpose of the Study:
- To achieve the micronization of PHBV using the supercritical antisolvent (SAS) technique.
- To evaluate the influence of operational parameters on particle size and distribution.
- To investigate the effect of hydroxyvalerate (HV) content on the morphology of PHBV microspheres.
Main Methods:
- Micronization of PHBV was performed using the SAS technique with dichloromethane (DCM) as the solvent.
- Experiments were conducted under varying conditions of CO(2) and liquid flow rates, temperature, and pressure.
- Particle size, particle size distribution, and morphology were analyzed.
Main Results:
- Microspheres with mean diameters ranging from 3 to 9 micrometers were successfully obtained.
- Optimal process conditions were identified as 40°C, 100 bar, 1 mL min⁻¹ liquid flow, and 10 L min⁻¹ carbon dioxide flow.
- Microsphere sphericity increased with a decrease in the hydroxyvalerate (HV) content of the polymer.
Conclusions:
- The SAS technique is effective for the micronization of PHBV.
- Process parameters significantly influence the characteristics of the resulting PHBV microspheres.
- Controlling HV content offers a method to tailor the morphology of PHBV powders for specific applications.
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