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Microviscosity and drug release from topical gel formulations
K I Al-Khamis1, S S Davis, J Hadgraft
1Department of Pharmacy, University of Nottingham, University Park, Nottingham, NG7 2RD, UK.
Pharmaceutical Research
|November 26, 2013
Summary
This study investigated gel microviscosity using dynamic light scattering to understand its impact on topical drug release. Findings link gel properties to the release rate of salicylate drugs.
Area of Science:
- Physical Chemistry
- Materials Science
- Pharmaceutical Sciences
Background:
- Gel formulations are crucial for topical drug delivery.
- Drug release from gels depends on drug activity and gel microviscosity.
Purpose of the Study:
- To probe the microviscosity of Carbopol gels using dynamic light scattering.
- To correlate gel microviscosity with the release of salicylate drugs.
Main Methods:
- Dynamic light scattering (DLS) was employed to measure the microviscosity of Carbopol gels.
- Polystyrene lattices of known particle size were dispersed in gels to observe scattering.
- The effects of gel concentration and temperature on microviscosity were analyzed.
Main Results:
- Gel microviscosity was successfully measured using DLS.
- Gel concentration and temperature significantly influenced microviscosity.
- A correlation was established between gel microviscosity and the release rate of salicylates.
Conclusions:
- Gel microviscosity is a key determinant of topical drug release.
- Controlling gel properties like concentration and temperature can modulate drug release kinetics.
- This research provides insights for optimizing gel-based topical drug delivery systems.
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