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Protein spheres prepared by drop jet freeze drying
Sören N Eggerstedt1, Mathias Dietzel, Martin Sommerfeld
1Laboratory of Pharmaceutical Technology and Biopharmaceutics, University of Bonn, Gerhard-Domagk-Str. 3, 53121 Bonn, Germany.
International Journal of Pharmaceutics
|September 11, 2012
Summary
Spray freeze drying using a novel drop jet nozzle produces uniform, free-flowing protein particles. This advanced method preserves enzyme activity, offering new pharmaceutical applications for lyophilizates.
Area of Science:
- Pharmaceutical Technology
- Biotechnology
- Materials Science
Background:
- Spray freeze drying (SFD) enables the production of flowable lyophilizates, expanding pharmaceutical applications beyond conventional freeze drying.
- Standard SFD methods often result in particles with broad size distributions, limiting their utility.
- Precise control over particle characteristics is crucial for developing advanced drug delivery systems.
Purpose of the Study:
- To introduce a drop jet nozzle for spray freeze drying to generate highly monodisperse particles.
- To investigate the impact of formulation and process parameters on particle properties.
- To evaluate the preservation of protein activity in the produced lyophilizates.
Main Methods:
- Utilized a drop jet nozzle for precise droplet generation in a spray freeze drying tower.
- Tested various formulations including lysozyme (model protein) with stabilizers (albumin, polyvinylpyrrolidone, dextran) and mannitol.
- Analyzed particle size distribution, morphology, and lysozyme activity post-drying.
Main Results:
- Achieved excellent free-flowing, nearly monodisperse, porous particles with controlled diameters (231 ± 3 μm to 310 ± 10 μm).
- Demonstrated full preservation of lysozyme activity (>94 ± 5%) across all tested formulations.
- Particle characteristics were successfully modulated by adjusting formulation composition and process conditions.
Conclusions:
- The novel drop jet nozzle spray freeze drying method effectively produces high-quality, monodisperse particulate lyophilizates.
- This technique ensures excellent protein stability and offers significant potential for pharmaceutical applications.
- The controlled particle properties make it suitable for various therapeutic uses requiring precise drug formulation.
