Controlling the processing of collagen-hydroxyapatite scaffolds for bone tissue engineering

Scaffolds are an important aspect of the tissue engineering approach to tissue regeneration. This study shows that it is possible to manufacture scaffolds from type I collagen with or without hydroxyapatite (HA) by critical point drying. The mean pore sizes of the scaffolds can be altered from 44 to 135 μm depending on the precise processing conditions. Such pore sizes span the range that is likely to be required for specific cells. The mechanical properties of the scaffolds have been measured and behave as expected of foam structures. The degradation rate of the scaffolds by collagenase is independent of pore size. Dehydrothermal treatment (DHT), a common method of physically crosslinking collagen, was found to denature the collagen at a temperature of 120∘C resulting in a decrease in the scaffold’s resistance to collagenase. Hybrid scaffold structures have also been manufactured, which have the potential to be used in the generation of multi-tissue interfaces. Microchannels are neatly incorporated via an indirect solid freeform fabrication (SFF) process, which could aid in reducing the different constraints commonly observed with other scaffolds.

[1]  D. Kaplan,et al.  Porosity of 3D biomaterial scaffolds and osteogenesis. , 2005, Biomaterials.

[2]  A. Boskey Will Biomimetics Provide New Answers for Old Problems of Calcified Tissues? , 1998, Calcified Tissue International.

[3]  R. Cortesini,et al.  Stem cells, tissue engineering and organogenesis in transplantation. , 2005, Transplant immunology.

[4]  S. Santoro,et al.  Identification of a tetrapeptide recognition sequence for the alpha 2 beta 1 integrin in collagen. , 1991, The Journal of biological chemistry.

[5]  U. Joos,et al.  Basic reactions of osteoblasts on structured material surfaces. , 2005, European cells & materials.

[6]  J. Orgel,et al.  Changes in collagen structure: drying, dehydrothermal treatment and relation to long term deterioration , 2000 .

[7]  B D Boyan,et al.  Role of material surfaces in regulating bone and cartilage cell response. , 1996, Biomaterials.

[8]  Anna Tampieri,et al.  Carbonated hydroxyapatite as bone substitute , 2003 .

[9]  I. Rehman,et al.  Characterization of hydroxyapatite and carbonated apatite by photo acoustic FTIR spectroscopy , 1997, Journal of materials science. Materials in medicine.

[10]  Alan Grodzinsky,et al.  Tissue-engineered composites for the repair of large osteochondral defects. , 2002, Arthritis and rheumatism.

[11]  Benjamin M. Wu,et al.  Scaffold fabrication by indirect three-dimensional printing. , 2005, Biomaterials.

[12]  Anthony Atala,et al.  Principals of neovascularization for tissue engineering. , 2002, Molecular aspects of medicine.

[13]  Wim E. Hennink,et al.  Novel crosslinking methods to design hydrogels , 2002 .

[14]  A J Bailey,et al.  Effect of chemical modifications on the susceptibility of collagen to proteolysis. II. Dehydrothermal crosslinking. , 1992, International journal of biological macromolecules.

[15]  S. Milz,et al.  Hydroxyapatite scaffolds for bone tissue engineering made by 3D printing , 2005, Journal of materials science. Materials in medicine.

[16]  W. Wallace,et al.  Clinical experience with a new artificial bone graft: preliminary results of a prospective study. , 1990, Injury.

[17]  F. Silver,et al.  Evaluation of collagen crosslinking techniques. , 1983, Biomaterials, medical devices, and artificial organs.

[18]  T. Vaimakis,et al.  Preparation of hydroxyapatite via microemulsion route. , 2003, Journal of colloid and interface science.

[19]  I. Brook,et al.  Tissue response to subperiosteal implantation of dense hydroxyapatite: case report. , 1989, Biomaterials.

[20]  P. Angele,et al.  Influence of different collagen species on physico-chemical properties of crosslinked collagen matrices. , 2004, Biomaterials.

[21]  J T Czernuszka,et al.  Collagen-hydroxyapatite composites for hard tissue repair. , 2006, European cells & materials.

[22]  Ioannis V. Yannas,et al.  Collagen and Gelatin in the Solid State , 1972 .

[23]  I. Heschel,et al.  Dendritic ice morphology in unidirectionally solidified collagen suspensions , 2000 .

[24]  Richard O C Oreffo,et al.  Bone tissue engineering: hope vs hype. , 2002, Biochemical and biophysical research communications.

[25]  Dietmar Werner Hutmacher,et al.  Application of micro CT and computation modeling in bone tissue engineering , 2005, Comput. Aided Des..

[26]  I. Yannas,et al.  Cross-linking of Gelatine by Dehydration , 1967, Nature.

[27]  F H Silver,et al.  Collagen fibres with improved strength for the repair of soft tissue injuries. , 1994, Biomaterials.

[28]  A. Bigi,et al.  Relationship between triple-helix content and mechanical properties of gelatin films. , 2004, Biomaterials.

[29]  P. Kelly Anatomy, physiology, and pathology of the blood supply of bones. , 1968, The Journal of bone and joint surgery. American volume.

[30]  H. Takita,et al.  Pore size of porous hydroxyapatite as the cell-substratum controls BMP-induced osteogenesis. , 1997, Journal of biochemistry.

[31]  B Derby,et al.  Novel collagen scaffolds with predefined internal morphology made by solid freeform fabrication. , 2003, Biomaterials.

[32]  H Shintani,et al.  Characterization of CO3Ap-collagen sponges using X-ray high-resolution microtomography. , 2004, Biomaterials.

[33]  S. Dedhar,et al.  A cell surface receptor complex for collagen type I recognizes the Arg- Gly-Asp sequence , 1987, The Journal of cell biology.

[34]  Yasuhiko Tabata,et al.  Effect of the fiber diameter and porosity of non-woven PET fabrics on the osteogenic differentiation of mesenchymal stem cells , 2004, Journal of biomaterials science. Polymer edition.

[35]  Giorgio Iannetti,et al.  Bone autografting of the calvaria and craniofacial skeleton: historical background, surgical results in a series of 15 patients, and review of the literature. , 2003, Surgical neurology.

[36]  K. E. Tanner,et al.  Interfaces in analogue biomaterials , 1998 .

[37]  K. Shakesheff,et al.  In vitro assessment of cell penetration into porous hydroxyapatite scaffolds with a central aligned channel. , 2004, Biomaterials.

[38]  L. Gibson,et al.  The effect of pore size on cell adhesion in collagen-GAG scaffolds. , 2005, Biomaterials.

[39]  A. Salgado,et al.  Nano- and micro-fiber combined scaffolds: A new architecture for bone tissue engineering , 2005, Journal of materials science. Materials in medicine.

[40]  M. Ashby,et al.  Engineering Materials 2: An Introduction to Microstructures, Processing and Design , 1986 .

[41]  S. Hollister,et al.  Optimal design and fabrication of scaffolds to mimic tissue properties and satisfy biological constraints. , 2002, Biomaterials.

[42]  E. J. Miller,et al.  Effect of physical crosslinking methods on collagen-fiber durability in proteolytic solutions. , 1996, Journal of biomedical materials research.

[43]  E. Sachlos,et al.  Making tissue engineering scaffolds work. Review: the application of solid freeform fabrication technology to the production of tissue engineering scaffolds. , 2003, European cells & materials.