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Preparation of Chitosan-based Injectable Hydrogels and Its Application in 3D Cell Culture
Published on: September 29, 2017
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pH-responsive chitosan based hydrogels affect the release of dapsone: Design, set-up, and physicochemical
Luíse L Chaves1, Alessandro Silveri2, Alexandre C C Vieira1
1LAQV-REQUIMTE, Laboratory of Applied Chemistry, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal.
International Journal of Biological Macromolecules
|April 30, 2019
Summary
This study developed pH-responsive hydrogels for controlled dapsone (DAP) release, improving leprosy treatment. These chitosan-based materials offer a promising approach to enhance DAP solubility and combat microbial resistance.
Area of Science:
- Polymer Science and Drug Delivery
- Materials Science
- Pharmaceutical Technology
Background:
- Dapsone (DAP) is crucial for treating leprosy but suffers from low solubility, limiting its therapeutic index and efficacy.
- Low solubility of DAP leads to challenges in achieving effective drug concentrations and contributes to microbial resistance.
- Interpenetrating polymer network (IPN)-hydrogels based on chitosan (CS) offer a potential solution for controlled DAP release due to tunable swelling properties.
Purpose of the Study:
- To synthesize and characterize novel pH-responsive chitosan/polymer hydrogels for controlled dapsone (DAP) release.
- To investigate the influence of different polymer combinations and cross-linking concentrations on hydrogel properties.
- To evaluate the in vitro release kinetics of DAP from the developed hydrogels at varying pH conditions.
Main Methods:
- Synthesis of chitosan-based IPN-hydrogels incorporating polyvinyl pyrrolidone, polyethylene glycol, and hydroxypropyl methylcellulose.
- Physicochemical characterization including swelling studies, rheological analysis, Fourier-transformed infrared (FT-IR) spectroscopy, and scanning electron microscopy (SEM).
- In vitro release studies of dapsone (DAP) from the hydrogels across a pH range of 1.2 to 6.8.
Main Results:
- Successfully synthesized pH-responsive hydrogels with varying polymer compositions and cross-linking densities.
- Demonstrated significant changes in hydrogel swelling properties in response to pH variations.
- Characterization confirmed successful incorporation of DAP and the structural integrity of the hydrogels.
- In vitro release studies showed pH-dependent dapsone (DAP) release profiles, with higher release at acidic pH.
Conclusions:
- pH-responsive chitosan/polymer hydrogels offer a viable strategy for the controlled release of dapsone (DAP).
- These developed hydrogels show potential for improving the therapeutic efficacy of DAP in leprosy treatment.
- The findings suggest that these hydrogels could form the basis for novel oral formulations against Mycobacterium leprae infections.
Keywords:
Anti-leprosy drugsControlled releaseDapsoneOral drug delivery systemsSwelling propertypH-responsive hydrogelsMore Related Videos
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