Effect of Cu- and Zn-Doped Bioactive Glasses on the In Vitro Bioactivity, Mechanical and Degradation Behavior of Biodegradable PDLLA Scaffolds
Abstract
:1. Introduction
2. Materials and Methods
2.1. Materials
2.2. Production of PDLLA/Metal-Doped Bioactive Glass Porous Scaffolds
2.3. Characterization
2.3.1. Scaffold Porosity
2.3.2. Mechanical Evaluation
2.3.3. In Vitro Bioactivity Evaluation in Simulated Body Fluid (SBF)
2.3.4. Degradation Studies in Phosphate Buffer Solution (PBS)
3. Results and Discussion
3.1. Porosity and Pore Morphology
3.2. Mechanical Properties
- (I)
- Associated with the elastic deformation of the dense material forming the pore walls. This elastic deformation is reversible meaning that the polymer chains return to their equilibrium position when the stress is retired. After around 5–8% of strain, this elastic zone gradually disappears without a defined yield point because of the high porosity of these scaffolds. This transition indicates a second zone
- (II)
- Characterized by a change in the stress variation with the deformation due to the bending of the pore walls and their plastic deformation [46]. Ending the plastic deformation, the pore structure collapses starting a third zone
- (III)
- ICharacterized by the densification of the specimen at around 30–40% deformation. This denser specimen can support more load, and thus the compressive strength becomes notably higher with an exponential behavior.
3.3. Apatite Formation in SBF
3.4. Degradation Behavior
4. Conclusions
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Scaffold Sample | ρ (g/cm3) | ρ0 (g/cm3) | p (%) |
---|---|---|---|
Neat PDLLA | 0.083 | 1.26 | 93.4 |
PLA/10-BG | 0.086 | 1.31 | 93.5 |
PLA/30-BG | 0.090 | 1.42 | 93.7 |
PLA/10-CuBG | 0.091 | 1.33 | 93.2 |
PLA/30-CuBG | 0.102 | 1.49 | 93.2 |
PLA/10-ZnBG | 0.095 | 1.33 | 92.8 |
PLA/30-ZnBG | 0.106 | 1.49 | 92.9 |
PLA/10-CuZnBG | 0.099 | 1.33 | 92.5 |
PLA/30-CuZnBG | 0.112 | 1.48 | 92.4 |
Scaffold | Compressive Strength at 10% Deformation (kPa) | Young’s Modulus (kPa) |
---|---|---|
PDLLA | 30 ± 3 | 2.3 ± 0.3 |
PLA/10-BG | 48 ± 7 | 5.3 ± 0.3 |
PLA/30-BG | 29 ± 4 | 3.1 ± 0.3 |
PLA/10-CuBG | 32 ± 4 | 4 ± 1 |
PLA/30-CuBG | 29 ± 3 | 3.5 ± 0.4 |
PLA/10-ZnBG | 24 ± 3 | 2.8 ± 0.6 |
PLA/30-ZnBG | 41 ± 6 | 5 ± 1 |
PLA/10-CuZnBG | 26 ± 3 | 2.8 ± 0.6 |
PLA/30-CuZnBG | 27 ± 3 | 2.8 ± 0.5 |
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Bejarano, J.; Boccaccini, A.R.; Covarrubias, C.; Palza, H. Effect of Cu- and Zn-Doped Bioactive Glasses on the In Vitro Bioactivity, Mechanical and Degradation Behavior of Biodegradable PDLLA Scaffolds. Materials 2020, 13, 2908. https://doi.org/10.3390/ma13132908
Bejarano J, Boccaccini AR, Covarrubias C, Palza H. Effect of Cu- and Zn-Doped Bioactive Glasses on the In Vitro Bioactivity, Mechanical and Degradation Behavior of Biodegradable PDLLA Scaffolds. Materials. 2020; 13(13):2908. https://doi.org/10.3390/ma13132908
Chicago/Turabian StyleBejarano, Julian, Aldo R. Boccaccini, Cristian Covarrubias, and Humberto Palza. 2020. "Effect of Cu- and Zn-Doped Bioactive Glasses on the In Vitro Bioactivity, Mechanical and Degradation Behavior of Biodegradable PDLLA Scaffolds" Materials 13, no. 13: 2908. https://doi.org/10.3390/ma13132908