A new hybrid scaffold constructed of solid freeform-fabricated PCL struts and collagen struts for bone tissue regeneration: fabrication, mechanical properties, and cellular activity

We propose a new technique for the fabrication of hybrid scaffolds using melt-plotting and a low temperature plate. This method is useful for the fabrication of a scaffold composed of heterogeneous biomaterials. We applied the new technique to collagen and polycaprolactone (PCL), which are stacked in interdigitated struts in successive layers to acquire a three-dimensional (3D) shape. The fabricated scaffolds exhibited a two-phase structure consisting of collagen struts to enhance the biological activity and PCL struts to increase the mechanical stability. They also exhibited a pore size under 100% pore interconnectivity appropriate for bone tissue regeneration. The fabricated hybrid scaffolds were assessed not only for mechanical properties, but also for biological capabilities by culturing osteoblast-like cells (MG63) on pure PCL, collagen, and hybrid scaffolds. Compared with the pure PCL scaffold, the hybrid scaffold exhibited higher biological activity, such as cell viability (an increase of about 27% at 7 days), alkaline phosphatase (ALP) activity (an increase of about 36% at 14 days), and calcium deposition. The pure collagen exhibited the highest value for most biological activities studied. In addition, the hybrid scaffolds exhibited a dramatic increase of Young's modulus compared to those of pure collagen scaffolds. These results suggest that this hybrid scaffold is potentially useful as a biomedical scaffold for bone tissue regeneration.

[1]  J. Sanders,et al.  Control of in vivo microvessel ingrowth by modulation of biomaterial local architecture and chemistry. , 2002, Journal of biomedical materials research.

[2]  Liu Yaxiong,et al.  Preparation of chitosan-gelatin hybrid scaffolds with well-organized microstructures for hepatic tissue engineering. , 2009, Acta biomaterialia.

[3]  Lorenzo Moroni,et al.  3D Fiber‐Deposited Electrospun Integrated Scaffolds Enhance Cartilage Tissue Formation , 2008 .

[4]  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.

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

[6]  Hyeongjin Lee,et al.  Three-dimensional plotted PCL/β-TCP scaffolds coated with a collagen layer: preparation, physical properties and in vitro evaluation for bone tissue regeneration , 2011 .

[7]  Xiaohong Li,et al.  Electrospun fibrous mats with high porosity as potential scaffolds for skin tissue engineering. , 2008, Biomacromolecules.

[8]  J. Mao,et al.  Study of novel chitosan-gelatin artificial skin in vitro. , 2003, Journal of biomedical materials research. Part A.

[9]  Guoping Chen,et al.  Tissue engineering of cartilage using a hybrid scaffold of synthetic polymer and collagen. , 2004, Tissue engineering.

[10]  S. Hollister.  Porous scaffold design for tissue engineering , 2005, Nature materials.

[11]  Dietmar W Hutmacher,et al.  The three-dimensional vascularization of growth factor-releasing hybrid scaffold of poly (epsilon-caprolactone)/collagen fibers and hyaluronic acid hydrogel. , 2011, Biomaterials.

[12]  A. Boccaccini,et al.  Biodegradable and bioactive porous polymer/inorganic composite scaffolds for bone tissue engineering. , 2006, Biomaterials.

[13]  Hyeongjin Lee,et al.  Three-Dimensional Collagen/Alginate Hybrid Scaffolds Functionalized with a Drug Delivery System (DDS) for Bone Tissue Regeneration , 2012 .

[14]  T. Kohgo,et al.  Effects of geometry of hydroxyapatite as a cell substratum in BMP-induced ectopic bone formation. , 2000, Journal of Biomedical Materials Research.

[15]  Peter X Ma,et al.  Biomimetic nanofibrous scaffolds for bone tissue engineering. , 2011, Biomaterials.

[16]  Hyeongjin Lee,et al.  Three-dimensional hierarchical composite scaffolds consisting of polycaprolactone, β-tricalcium phosphate, and collagen nanofibers: fabrication, physical properties, and in vitro cell activity for bone tissue regeneration. , 2011, Biomacromolecules.

[17]  Tetsuya Tateishi,et al.  A cell leakproof PLGA‐collagen hybrid scaffold for cartilage tissue engineering , 2009, Biotechnology progress.

[18]  W. L. Francis,et al.  A multiscale modeling approach to scaffold design and property prediction. , 2010, Journal of the mechanical behavior of biomedical materials.

[19]  Li-Hsin Han,et al.  Fabrication of three-dimensional scaffolds for heterogeneous tissue engineering , 2010, Biomedical microdevices.

[20]  GeunHyung Kim,et al.  Designed three-dimensional collagen scaffolds for skin tissue regeneration. , 2010, Tissue engineering. Part C, Methods.

[21]  M. Stevens,et al.  Carbon nanotube-enhanced polyurethane scaffolds fabricated by thermally induced phase separation , 2008 .

[22]  Hyeongjin Lee,et al.  Cryogenically fabricated three-dimensional chitosan scaffolds with pore size-controlled structures for biomedical applications , 2011 .

[23]  Scott J Hollister,et al.  The pore size of polycaprolactone scaffolds has limited influence on bone regeneration in an in vivo model. , 2010, Journal of biomedical materials research. Part A.

[24]  A. Barbetta,et al.  Polysaccharide based scaffolds obtained by freezing the external phase of gas-in-liquid foams , 2010 .

[25]  K. Shakesheff,et al.  The influence of dispersant concentration on the pore morphology of hydroxyapatite ceramics for bone tissue engineering. , 2005, Biomaterials.

[26]  K J Gooch,et al.  Biomaterial-microvasculature interactions. , 2000, Biomaterials.

[27]  G. Bowlin,et al.  Incorporating platelet-rich plasma into electrospun scaffolds for tissue engineering applications. , 2011, Tissue engineering. Part A.

[28]  Dong-Yol Yang,et al.  Development of dual scale scaffolds via direct polymer melt deposition and electrospinning for applications in tissue regeneration. , 2008, Acta biomaterialia.

[29]  Amit Bandyopadhyay,et al.  Development of controlled porosity polymer-ceramic composite scaffolds via fused deposition modeling , 2003 .

[30]  E. Toyserkani,et al.  Solid freeform fabrication and characterization of porous calcium polyphosphate structures for tissue engineering purposes. , 2010, Journal of biomedical materials research. Part B, Applied biomaterials.

[31]  Rui L Reis,et al.  Three-dimensional plotted scaffolds with controlled pore size gradients: Effect of scaffold geometry on mechanical performance and cell seeding efficiency. , 2011, Acta biomaterialia.

[32]  Xiaobing Fu,et al.  Naturally derived materials-based cell and drug delivery systems in skin regeneration. , 2010, Journal of controlled release : official journal of the Controlled Release Society.

[33]  David J J de Gorter,et al.  Biphasic effects of transforming growth factor β on bone morphogenetic protein–induced osteoblast differentiation , 2011, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[34]  Shu-ying Gu,et al.  Preparation and characterization of porous PDLLA/HA composite foams by supercritical carbon dioxide technology. , 2007, Journal of biomedical materials research. Part B, Applied biomaterials.

[35]  D. Chappard,et al.  Effects of Roughness, Fibronectin and Vitronectin on Attachment, Spreading, and Proliferation of Human Osteoblast-Like Cells (Saos-2) on Titanium Surfaces , 1999, Calcified Tissue International.

[36]  Julie Glowacki,et al.  Collagen scaffolds for tissue engineering. , 2008, Biopolymers.

[37]  J. Vacanti,et al.  Tissue engineering : Frontiers in biotechnology , 1993 .

[38]  GeunHyung Kim,et al.  A cryogenic direct-plotting system for fabrication of 3D collagen scaffolds for tissue engineering , 2009 .

[39]  J. Feijen,et al.  Immobilization of heparin to EDC/NHS-crosslinked collagen. Characterization and in vitro evaluation. , 2001, Biomaterials.

[40]  Hyeongjin Lee,et al.  Designed hybrid scaffolds consisting of polycaprolactone microstrands and electrospun collagen-nanofibers for bone tissue regeneration. , 2011, Journal of biomedical materials research. Part B, Applied biomaterials.

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

[42]  Christian Jungreuthmayer,et al.  Development of a biomimetic collagen-hydroxyapatite scaffold for bone tissue engineering using a SBF immersion technique. , 2009, Journal of biomedical materials research. Part B, Applied biomaterials.

[43]  Johnny Huard,et al.  Synergistic enhancement of bone formation and healing by stem cell-expressed VEGF and bone morphogenetic protein-4. , 2002, The Journal of clinical investigation.