Sol-Gel Synthesized Silica/Sodium Alginate Hybrids: Comprehensive Physico-Chemical and Biological Characterization
Antonio D'Angelo1, Cecilia Mortalò2, Lara Comune3
1Department of Engineering, University of Campania "Luigi Vanvitelli", Via Roma 29, 81031 Aversa, Italy.
Molecules (Basel, Switzerland)
|September 13, 2025
Summary
Amorphous silica/sodium alginate hybrids were synthesized for biomedical uses. Higher sodium alginate content improved biocompatibility, with SiO2/SA5% showing the best balance of properties.
Area of Science:
- Materials Science
- Biomaterials Engineering
- Nanotechnology
Background:
- Biomaterials with tailored properties are crucial for biomedical applications.
- Developing novel organic-inorganic hybrid materials is an active area of research.
Purpose of the Study:
- To synthesize and characterize amorphous silica/sodium alginate (SiO2/SA) hybrids.
- To evaluate the structural, surface, thermal, moisture-responsive, and biological properties of these hybrids.
- To determine the optimal sodium alginate content for balancing functional properties and biocompatibility.
Main Methods:
- Sol-gel synthesis of SiO2/SA hybrids with varying SA content (2%, 5%, 8%).
- Characterization using FTIR, XRD, BET surface area analysis, thermal analysis (TGA/DSC), and moisture sorption tests.
- In vitro cytotoxicity assessment using HaCaT cells.
Main Results:
- FTIR and XRD confirmed the formation of amorphous organic-inorganic networks.
- Specific surface area decreased from 325 m²/g (SiO2/SA2%) to 104.3 m²/g (SiO2/SA8%).
- Moisture sorption capacity and thermal stability increased with SA content.
- Cytotoxicity decreased with increasing SA content, with SiO2/SA8% showing ~15% CVI, within non-toxic ranges.
- SiO2/SA5% exhibited the best balance of properties and biocompatibility.
Conclusions:
- Silica/sodium alginate hybrids show tunable properties and reduced cytotoxicity with increased SA content.
- The SiO2/SA5% hybrid presents a promising candidate for biomedical applications.
- Further optimization of SA concentration could enhance biocompatibility while maintaining desirable material characteristics.
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