Stability of the Magnesium Carbonate Apatite/Anionic Collagen Scaffolds: Effect of the Cross-Link Concentration

Abstract:

Natural bone constitutes of an inorganic phase (a biological nanoapatite) and an organic phase (mostly type I collagen). The challenge is to develop a material that can regenerate lost bone tissue with degradation and resorption kinetics compatible with the new bone formation. The aim of this study was to prepare self-organized magnesium and carbonate substituted apatite/collagen scaffolds, cross-linked with glutaraldehyde (GA). Bovine tendon was submitted to alkaline treatment resulting in a negatively charged collagen surface. The scaffolds were prepared by precipitation: simultaneous dropwise addition of solution containing calcium (Ca) and magnesium (Mg) ions and collagen into a buffered solution containing carbonate and phosphate ions in reaction vessel maintained at 37 °C, pH=8. The reaction products were cross-linked with 0.125 and 0.25% (v/v) glutaraldehyde (GA) solution and freeze-dried. The samples were characterized by Fourier-transformed infrared spectroscopy (FTIR). In vitro cytotoxicity (based on three parameters assays) and scaffolds degradation in culture medium and osteoblastic cells culture were performed in the cross-linked materials. No cytotoxic effects were observed. The cross-linked samples with the lower GA concentration showed a lower stability when placed in contact with culture medium. Human osteoblasts attached on the scaffolds surface cross-linked with 0.25% GA, forming a continuous layer after 14 days of incubation. These results showed potential application of the designed scaffolds for bone tissue engineering.

• Periodical: Key Engineering Materials (Volumes 493-494)
• Pages: 844-848
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.493-494.844
• Online since: October 2011
• Authors: Marcia S. Sader, Gutemberg Alves, Racquel Z. LeGeros, Gloria Dulce de Almeida Soares
• Keywords: 3D Scaffolds, Cross-Linked Scaffold, Substituted Apatite

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