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Theophylline cocrystals prepared by spray drying: physicochemical properties and aerosolization performance
Amjad Alhalaweh1, Waseem Kaialy, Graham Buckton
1Pharmaceutical Materials Research Group, Department of Health Science, Luleå University of Technology, Luleå, 971 87, Sweden.
AAPS Pharmscitech
|January 9, 2013
Summary
Spray drying effectively produced theophylline (THF) cocrystals with varied properties for inhalation. Theophylline-nicotinamide cocrystals demonstrated superior aerosol performance, indicating spray drying
Area of Science:
- Pharmaceutical Sciences
- Materials Science
- Drug Delivery
Background:
- Theophylline (THF) is a drug commonly delivered via inhalation.
- Cocrystallization is a strategy to modify drug physicochemical properties.
- Spray drying is a potential method for producing inhalation particles.
Purpose of the Study:
- To characterize the physicochemical properties of theophylline cocrystals prepared by spray drying.
- To evaluate the in vitro inhalation performance of these cocrystals.
- To compare spray-dried cocrystals with milled counterparts.
Main Methods:
- Theophylline cocrystals with urea, saccharin, and nicotinamide were prepared using spray drying.
- Physicochemical properties (purity, particle size, morphology, surface energy) were analyzed.
- In vitro aerosol performance was assessed using multi-stage liquid impinger and next-generation impactor.
Main Results:
- Spray-dried particles exhibited varied size distributions, morphologies, and surface energies.
- Milled samples showed higher surface energy compared to spray-dried ones.
- Theophylline-nicotinamide cocrystals demonstrated the best aerosolization performance, followed by urea and saccharin cocrystals.
Conclusions:
- Spray drying is a viable technique for preparing theophylline cocrystals with tunable properties for inhalation.
- Micromeritic properties, rather than surface energy, were found to be dominant factors in aerosol performance.
- Theophylline-nicotinamide cocrystals show promise for dry powder inhaler formulations.
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