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Acyclovir delivery matrices based on poly(ethylene glycol)/chitosan semi-interpenetrating networks
O Diez-Sales1, M Dolz, M J Hernandez
1Department of Pharmacy and Pharmaceutical Technology, Faculty of Pharmacy, University of Valencia, Avda Vicente Andrés Estellés s/n, 46100-Burjassot, Valencia, Spain. octavio.diez@uv.es
Journal of Pharmaceutical Sciences
|February 9, 2007
Summary
This study explored chitosan matrix systems for prolonged acyclovir (ACV) release. Complex viscosity effectively predicted drug release rates, offering a valuable tool for formulation development.
Area of Science:
- Materials Science
- Pharmaceutical Sciences
- Polymer Chemistry
Background:
- Chitosan matrix systems show promise for sustained drug delivery.
- Acyclovir (ACV) is an antiviral medication requiring effective delivery systems.
- Understanding formulation properties is crucial for controlled drug release.
Purpose of the Study:
- To investigate the impact of chitosan concentration and glyoxal crosslinking on the viscoelastic properties of chitosan-poly(ethylene glycol) 400 formulations.
- To analyze the acyclovir (ACV) release kinetics from these matrix systems.
- To correlate viscoelastic parameters with ACV diffusion coefficients for predictive modeling.
Main Methods:
- Formulations were prepared using varying chitosan concentrations (0.83%–1.67%) with and without glyoxal crosslinking.
- Viscoelastic properties were analyzed by measuring storage modulus (G') and loss modulus (G'').
- Acyclovir (ACV) release rates and diffusion coefficients (D) were determined experimentally.
Main Results:
- Chitosan-poly(ethylene glycol) 400 formulations without glyoxal exhibited non-structured system behavior (G'' > G').
- Addition of glyoxal resulted in gelled matrices (G' > G'') for higher chitosan concentrations, indicating crosslinking.
- Acyclovir (ACV) diffusion coefficients were lower in crosslinked matrices and dependent on crosslink density.
- Complex viscosity (eta*) showed a strong correlation with ACV diffusion coefficients (D).
Conclusions:
- Viscoelastic properties, particularly complex viscosity, can predict acyclovir (ACV) release rates from chitosan-based matrices.
- Glyoxal crosslinking significantly influences the matrix structure and drug release characteristics.
- Chitosan matrix systems offer tunable properties for controlled antiviral drug delivery.
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