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Influence of Alginate Properties and Calcium Chloride Concentration on Alginate Bead Reticulation and Size: A
Chanez Bennacef1,2, Stéphane Desobry1, Jordane Jasniewski1
1Université de Lorraine, Laboratoire d'Ingénierie des Biomolécules (LIBio), ENSAIA, 54000 Nancy, France.
Polymers
|October 28, 2023
Summary
This study optimized alginate bead production using electro-vibratory extrusion. Calcium chloride concentration, alginate molecular weight, and M/G ratio significantly influence bead size, enabling tailored material properties.
Area of Science:
- Biomaterials Engineering
- Polymer Science
- Chemical Engineering
Background:
- Alginate beads are versatile biomaterials used in drug delivery and tissue engineering.
- Controlling alginate bead size is crucial for optimizing their performance in various applications.
- Electro-vibratory extrusion offers a precise method for alginate bead formation.
Purpose of the Study:
- To investigate the key factors affecting alginate bead size produced by electro-vibratory extrusion.
- To establish a phenomenological model for alginate reticulation and bead formation.
- To provide insights for tailoring alginate materials for specific applications.
Main Methods:
- Production of alginate beads using two alginate types (AlgLF and AlgP) via electro-vibratory extrusion.
- Characterization of alginate properties, including Mannuronate/Guluronate (M/G) ratio and molecular weight, using NMR and SEC-MALS.
- Systematic variation of process parameters: calcium chloride concentration, flow rate, and vibration frequency.
- Mathematical modeling of the alginate reticulation process.
Main Results:
- Calcium chloride concentration was the dominant factor influencing bead size, with higher concentrations yielding smaller beads.
- Alginate molecular weight and M/G ratio also significantly impacted bead size; higher molecular weight and lower G-block content resulted in smaller beads.
- Flow rate and vibration frequency influenced bead size, while alginate solution aging had a minimal effect.
- A mathematical equation was developed to model alginate reticulation.
Conclusions:
- Alginate bead size is controllable through electro-vibratory extrusion by manipulating calcium ion concentration, alginate molecular weight, and M/G ratio.
- The findings offer a basis for optimizing alginate-based materials for diverse applications.
- A phenomenological model aids in understanding and tailoring the gelling process for customized alginate materials.
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