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Preparation and Characterization of Individual and Multi-drug Loaded Physically Entrapped Polymeric Micelles
Published on: August 28, 2015
Optimisation and characterisation of bioadhesive controlled release tetracycline microspheres
S Govender1, V Pillay, D J Chetty
1School of Pharmacy and Pharmacology, University of KwaZulu-Natal, Private Bag X54001, Durban 4000, South Africa.
International Journal of Pharmaceutics
|October 26, 2005
Summary
This study optimized tetracycline microspheres using a Box-Behnken design for enhanced bioadhesion and controlled release. The ideal formulation demonstrated effective antimicrobial activity against Staphylococcus aureus.
Area of Science:
- Pharmaceutical Sciences
- Materials Science
Background:
- Developing effective drug delivery systems is crucial for improving therapeutic outcomes.
- Microspheres offer potential for controlled release and targeted delivery of active pharmaceutical ingredients.
- Tetracycline is an antibiotic requiring optimized delivery for sustained efficacy.
Purpose of the Study:
- To optimize the formulation of tetracycline microspheres for maximum bioadhesivity and controlled drug release.
- To predict the quantitative effects of formulation parameters on bioadhesion and drug release.
- To characterize the optimal tetracycline microsphere preparation.
Main Methods:
- Box-Behnken experimental design for statistical optimization.
- Formulation of chitosan-tripolyphosphate microspheres loaded with tetracycline hydrochloride.
- Characterization including hydration dynamics, release kinetics, antimicrobial activity, thermal analysis, morphology (SEM), and surface pH.
- Analysis of drug release using kinetic models (Fickian diffusion).
Main Results:
- An optimal formulation of 3% chitosan, 10% tetracycline HCl, and 9% tripolyphosphate was identified.
- Drug release followed Fickian diffusion kinetics with minimal hydration.
- Antimicrobial studies confirmed concentrations above the minimum inhibitory concentration for Staphylococcus aureus.
- Scanning electron microscopy revealed microsphere integrity and morphological changes post-drug release.
- Surface pH remained stable and similar to salivary pH.
Conclusions:
- The optimized tetracycline microspheres exhibit excellent bioadhesivity and controlled release properties.
- The formulation demonstrates sustained antimicrobial efficacy, suitable for potential oral or mucosal applications.
- Further investigation into drug-polymer interactions and in vivo performance is warranted.
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