Fabrication of silicate-based bioactive glass-containing sodium alginate hydrogel microfibers for tissue engineering applications
摘要
Sodium alginate (SA) is a natural anionic polysaccharide widely used in tissue engineering due to its biocompatibility and hydrogel-forming ability in the presence of multivalent cations. However, conventional calcium ion-based crosslinking methods often result in low bioactivity and poor printing precision. In this study, silicate-based bioactive glass (BG) particles were incorporated into SA to enhance bioactivity and crosslinking efficiency. Composite SA-BG hydrogel microfibers were fabricated via extrusion-based 3D printing and cross-linked using CaCl₂ solution.
Morphological analysis showed fiber diameters ranging from 282 ± 23 μm to 385 ± 34 μm, increasing with BG content. Mineralization behavior was evaluated in simulated body fluid (SBF) and phosphate-buffered saline (PBS), confirming hydroxyapatite (HA) formation dependent on BG concentration. HA deposition began on day 3 in PBS and day 14 in SBF. In addition, degradation behavior and the controlled release of amoxicillin (AMOX) were investigated. Kinetic modeling indicated that AMOX release followed the Korsmeyer–Peppas model during the initial 48 h. The maximum cumulative release reached 26.42% after 408 h. Increasing BG content reduced both degradation and drug release rates. 13–93 bioactive glass–containing alginate microfibers exhibited good cytocompatibility with both human intestinal fibroblasts and HT-29 colon adenocarcinoma cells, while significantly enhancing fibroblast metabolic activity at higher glass contents, supporting their potential for tissue engineering applications.