Chemically Crosslinked Alginate Hydrogel with Polyaziridine: Effects on Physicochemical Properties and Promising
Chaehoon Lee1,2, Giacomo Fiocco2,3, Barbara Vigani4
1Department of Chemistry, University of Pavia, Via Taramelli 12, 27100, Pavia, Italy.
Chempluschem
|December 10, 2024
Summary
Chemically cross-linked calcium-alginate hydrogels (CA-CHEM) were developed using pentaerythritol tris[3-(1-aziridinyl)propionate] (PTAP). These enhanced gels show improved stability and controlled water release, ideal for sensitive surfaces.
Area of Science:
- Biomaterials Science
- Polymer Chemistry
- Materials Engineering
Background:
- Alginate biopolymers offer biodegradability, biocompatibility, and low toxicity, making them versatile for various industrial applications.
- Calcium-alginate hydrogels are widely used but can be enhanced for tailored mechanical and moisture properties.
- Chemical cross-linking presents an opportunity to improve the performance of alginate-based hydrogels.
Purpose of the Study:
- To develop novel chemically cross-linked calcium-alginate hydrogels (CA-CHEM) with enhanced properties.
- To investigate the effect of pentaerythritol tris[3-(1-aziridinyl)propionate] (PTAP) cross-linking on alginate hydrogel characteristics.
- To evaluate the potential of these new hydrogels for controlled delivery applications.
Main Methods:
- Synthesis of CA-CHEM gels by reacting alginate with varying ratios of PTAP.
- Monitoring the cross-linking reaction using Nuclear Magnetic Resonance (NMR).
- Characterization using Fourier-Transform Infrared Attenuated Total Reflectance (FTIR-ATR), Scanning Electron Microscopy (SEM), thermogravimetric analysis (TGA), and mechanical testing.
- Assessment of water absorption and release properties.
Main Results:
- Successful chemical cross-linking of alginate with PTAP was confirmed by NMR and FTIR-ATR.
- SEM analysis revealed altered porosity and network homogeneity in CA-CHEM gels.
- Thermogravimetric analysis and mechanical tests indicated improved degradation stability and structural strength with increasing PTAP content (up to 1% w/w).
- CA-CHEM gels demonstrated effective control over water absorption and release, with CA-CHEM-1 showing the most controlled system.
Conclusions:
- The developed CA-CHEM gels exhibit enhanced mechanical properties and degradation stability compared to plain calcium-alginate hydrogels.
- PTAP cross-linking effectively modifies the network structure and water management capabilities of alginate hydrogels.
- The CA-CHEM-1 formulation shows significant promise for controlled delivery of aqueous solutions, particularly for water-sensitive surfaces like historical wooden musical instruments.
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