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A particulate pulse-release system and mathematical description with the Maxwell-Stefan theory
P J Hartman Kok1, P Vonk, N W Kossen
1Department of Industrial Pharmacy, University of Groningen, 9713 AV, Groningen, The Netherlands. P.J.A.Hartman.Kok@farm.rug.nl
Summary
This study presents a novel delayed-release system using UV-crosslinked coatings that swell in water to control drug release. The system achieves a pulse-release profile after a tunable lag-time, validated by a mathematical model.
Area of Science:
- Pharmaceutical Technology
- Materials Science
- Chemical Engineering
Background:
- Developing controlled drug delivery systems is crucial for optimizing therapeutic efficacy.
- Delayed-release formulations require precise control over drug release kinetics.
- Swelling-controlled coatings offer a promising mechanism for achieving predictable drug release profiles.
Purpose of the Study:
- To develop a multi-particulate delayed-release system with swelling-dependent release properties.
- To create and validate a mathematical model describing the release characteristics of the developed system.
- To investigate the influence of coating parameters on lag-time and release profiles.
Main Methods:
- Formulation of a water-soluble core coated with a copolymer of methacrylic acid and ethyl acrylate.
- Incorporation of pentaerythritol triacrylate for UV crosslinking to form a swellable network.
- Characterization of swelling kinetics and release profiles in aqueous environments.
- Development and application of a mathematical model to predict release behavior.
- Estimation of Maxwell-Stefan diffusion coefficients for water in the coating.
Main Results:
- The UV-crosslinked coating swells upon hydration, increasing its permeability and enabling drug release.
- A pulse-release profile, characterized by a lag-time followed by rapid release, was achieved.
- Coating thickness and UV crosslinking duration were identified as key parameters to adjust lag-time.
- The developed mathematical model accurately predicted the experimental release times.
- Observed relationships between Maxwell-Stefan diffusion coefficients and water mole fraction differed from existing literature.
Conclusions:
- The developed multi-particulate system effectively provides delayed and pulse-like drug release.
- The mathematical model offers a reliable tool for predicting and optimizing the performance of such delivery systems.
- The findings contribute to the understanding of swelling-controlled release mechanisms and diffusion in polymer coatings.
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