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Double Emulsion Generation Using a Polydimethylsiloxane PDMS Co-axial Flow Focus Device
Published on: December 25, 2015
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A continuous flow method for estimation of drug release rates from emulsion formulations
Lotta Salmela1, Clive Washington1
1Pharmaceutical Development, AstraZeneca, Hurdsfield Road, Macclesfield, Cheshire SK10 2NA, UK.
International Journal of Pharmaceutics
|June 20, 2014
Summary
A new continuous-flow method measures drug release from colloidal carriers in milliseconds. This confirms rapid diffusion controls release from lipid emulsions, challenging their use as sustained-release formulations.
Area of Science:
- Pharmaceutical Sciences
- Materials Science
- Chemical Engineering
Background:
- Assessing drug release kinetics from colloidal carriers is crucial for formulation development.
- Traditional methods like dialysis and centrifugation lack the temporal resolution for rapidly releasing systems.
Purpose of the Study:
- To develop and validate a continuous-flow method for millisecond-timescale drug release analysis.
- To investigate the release mechanism of tetracaine from lipid emulsions.
Main Methods:
- A novel continuous-flow technique was employed for real-time drug release measurements.
- The method was applied to study tetracaine release from submicron lipid emulsions.
Main Results:
- The study successfully measured drug release on a millisecond timescale.
- Results indicated that drug release from lipid emulsions is primarily governed by rapid intra-droplet diffusion.
- The findings validate the limitations of slower conventional release assay methods.
Conclusions:
- Continuous-flow analysis provides critical insights into rapid drug release mechanisms.
- Simple lipid emulsions are unlikely to function as effective sustained-release formulations due to rapid diffusion.
- The developed method offers a superior alternative for characterizing fast-releasing drug delivery systems.
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