Octacalcium Phosphate/Calcium Citrate/Methacrylated Gelatin Composites: Optimization of Photo-Crosslinking Conditions and Osteogenic Potential Evaluation
Abstract
1. Introduction
2. Results
2.1. Influence of Photoinitiator Volumetric Ratio and Blue Light Exposure Time on Crosslinking of 35% OCP/35% CC/30% GelMA
2.2. Assessment of Initial Structural Stability of the 35% OCP/35% CC/30% GelMA Composite After Soaking in SBF and Ultrapure Water
2.3. Conversion of 35% OCP/35% CC/30% GelMA and 35% OCP/35% CC/30% Pig Gel Immersed in Simulated Body Fluid
2.4. Comparison of Functional Groups in GelMA and Pig Gel After Crosslinking
3. Discussion
4. Materials and Methods
4.1. Synthesis of the 35% OCP/35% CC/30% GelMA Composite, 35% OCP/35% CC/30% Pig Gel Composite, Pure GelMA Film, and Pig Gel Film
4.2. Soaking in Simulated Body Fluid
4.3. Characterization
5. Conclusions
- The composite exhibits superior structural stability in SBF compared to pig Gel-based composites, which degrade rapidly in SBF.
- Optimized photo-crosslinking with LAP and blue light enables uniform gelation of 35% OCP/35% CC/30% GelMA.
- The composite sustains HAp formation in SBF, supporting osteoconductivity; however, its nucleation efficiency is lower than that observed in pig Gel composites.
- The reduced carboxy content in GelMA possibly contributes to the decreased HAp nucleation, providing insights for further material optimization.
- The enhanced stability, controlled synthesis, and ability to form HAp in SBF position the composite as a promising scaffold material for bone regeneration applications.
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
Abbreviations
OCP | octacalcium phosphate |
CC | calcium citrate |
Gel | gelatin |
GelMA | methacrylated gelatin |
SBF | simulated body fluid |
HAp | hydroxyapatite |
XRD | X-ray diffraction |
SEM | scanning electron microscopy |
FTIR | Fourier-transform infrared |
ATR | attenuated total reflectance |
EDS | energy-dispersive X-ray spectroscopy |
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Volumetric Ratio (v/v) of LAP Photoinitiator in GelMA | Blue Light Exposure Time (min) | Sample Status After Blue Light Exposure |
---|---|---|
0.02 | 2 | Fluid |
4 | Fluid | |
0.06 | 1 | Fluid |
1.5 | Fluid | |
0.08 | 1 | Fluid |
1.5 | Upper side gelled Bottom side fluid | |
0.1 | 1 | Fluid |
1.5 | Upper side gelled Bottom side fluid | |
2 | Upper side gelled Bottom side fluid | |
2.5 | Both sides gelled |
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Wang, Y.; Yokoi, T.; Shimabukuro, M.; Kawashita, M. Octacalcium Phosphate/Calcium Citrate/Methacrylated Gelatin Composites: Optimization of Photo-Crosslinking Conditions and Osteogenic Potential Evaluation. Int. J. Mol. Sci. 2025, 26, 6889. https://doi.org/10.3390/ijms26146889
Wang Y, Yokoi T, Shimabukuro M, Kawashita M. Octacalcium Phosphate/Calcium Citrate/Methacrylated Gelatin Composites: Optimization of Photo-Crosslinking Conditions and Osteogenic Potential Evaluation. International Journal of Molecular Sciences. 2025; 26(14):6889. https://doi.org/10.3390/ijms26146889
Chicago/Turabian StyleWang, Yuejun, Taishi Yokoi, Masaya Shimabukuro, and Masakazu Kawashita. 2025. "Octacalcium Phosphate/Calcium Citrate/Methacrylated Gelatin Composites: Optimization of Photo-Crosslinking Conditions and Osteogenic Potential Evaluation" International Journal of Molecular Sciences 26, no. 14: 6889. https://doi.org/10.3390/ijms26146889
APA StyleWang, Y., Yokoi, T., Shimabukuro, M., & Kawashita, M. (2025). Octacalcium Phosphate/Calcium Citrate/Methacrylated Gelatin Composites: Optimization of Photo-Crosslinking Conditions and Osteogenic Potential Evaluation. International Journal of Molecular Sciences, 26(14), 6889. https://doi.org/10.3390/ijms26146889