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Particle Surface Roughness Improves Colloidal Stability of Pressurized Pharmaceutical Suspensions
Hui Wang1, David S Nobes1, Reinhard Vehring2
1Department of Mechanical Engineering, 10-269 Donadeo Innovation Centre for Engineering, University of Alberta, Edmonton, Alberta, T6G 1H9, Canada.
Pharmaceutical Research
|February 1, 2019
Summary
Smaller particle size and increased surface roughness significantly enhance colloidal stability in pharmaceutical suspensions. Surface modification using trileucine improved suspension stability in pressurized metered dose inhalers.
Area of Science:
- Pharmaceutical Science
- Materials Science
- Colloid Science
Background:
- Pressurized pharmaceutical suspensions require stable colloidal formulations for effective drug delivery.
- Particle characteristics, including size and surface properties, critically influence suspension stability.
- Understanding these factors is crucial for developing robust inhalation products.
Purpose of the Study:
- To investigate the impact of particle size and surface roughness on the colloidal stability of pharmaceutical suspensions.
- To evaluate the efficacy of spray-dried monodisperse particles in pressurized systems.
- To explore surface modification strategies for enhancing suspension performance.
Main Methods:
- Characterized colloidal stability of suspensions in HFA227ea propellant using shadowgraphic imaging.
- Quantified stability using an instability index.
- Studied size-dependent stability with trehalose particles (5.98 µm, 10.1 µm, 15.5 µm).
- Assessed surface roughness effects by incorporating trileucine (shell former) at varying concentrations.
Main Results:
- Colloidal stability significantly improved with decreasing particle size (5.98 µm particles showed higher stability than 15.5 µm).
- Increased particle surface roughness, achieved with higher trileucine fractions (1.0% and 5.0%), substantially decreased the instability index.
- Low trileucine fractions (0.4%) did not significantly improve stability, indicating a threshold effect for surface modification.
Conclusions:
- Particle size is a critical determinant of colloidal stability in pressurized pharmaceutical suspensions.
- Surface modification via spray drying with shell formers like trileucine effectively enhances particle properties and improves suspension stability.
- This approach offers a promising strategy for optimizing pharmaceutical suspensions in metered dose inhalers.
Keywords:
monodisperse spray dryingparticle formationshadowgraphic imagingsurface roughnesssuspension stabilityMore Related Videos
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