Progress of three-dimensional macroporous bioactive glass for bone regeneration

Abstract

Bioactive glasses (BGs) are ideal materials for macroporous scaffolds due to their excellent osteoconductive, osteoinductive, biocompatible and biodegradable properties, and their high bone bonding rates. Macroporous scaffolds made from BGs are in high demand for bone regeneration because they can stimulate vascularized bone ingrowth and they enhance bonding between scaffolds and surrounding tissues. Engineering BG/biopolymers (BP) composites or hybrids may be a good way to prepare macroporous scaffolds with excellent properties. This paper summarizes the progress in the past few years in preparing three-dimensional macroporous BG and BG/BP scaffolds for bone regeneration. Since the brittleness of BGs is a major problem in developing macroporous scaffolds and this limits their use in load bearing applications, the mechanical properties of macroporous scaffolds are particularly emphasized in this review.

Keywords

bioactive glass / biopolymer / bone regeneration / macroporous scaffolds / tissue engineering

References

[1] Hench L L, Thompson I. Twenty-first century challenges for biomaterials. Journal of the Royal Society, Interface, 2010, 7(Suppl_4): S379–S391

[2] Arcos D, Vallet-Regi M. Sol-gel silica-based biomaterials and bone tissue regeneration. Acta Biomaterialia, 2010, 6(8): 2874–2888

[3] Boccaccini A R, Keim S, Ma R, Li Y, Zhitomirsky I. Electrophoretic deposition of biomaterials. Journal of the Royal Society, Interface, 2010, 7(Suppl_5): S581–S613

[4] Gorustovich A A, Roether J A, Boccaccini A R. Effect of bioactive glasses on angiogenesis: a review of in vitro and in vivo evidences. Tissue Engineering Part B: Reviews, 2010, 16(2): 199–207

[5] Hertz A, Bruce I J. Inorganic materials for bone repair or replacement applications. Nanomedicine; Nanotechnology, Biology, and Medicine, 2007, 2: 899–918

[6] Hench L L, Xynos I D, Polak J M. Bioactive glasses for in situ tissue regeneration. Journal of Biomaterials Science. Polymer Edition, 2004, 15(4): 543–562

[7] Hench L L, Splinter R J, Allen W C, Greenlee T K. Bonding mechanisms at the interface of ceramic prosthetic materials. Journal of Biomedical Materials Research, 1971, 5(6): 117–141

[8] Hulbert S F, Young F A, Mathews R S, Klawitter J J, Talbert C D, Stelling F H. Potential of ceramic materials as permanently skeletal prostheses. Journal of Biomedical Materials Research, 1970, 4(3): 433–456

[9] Gauthier O, Bouler J M, Aguado E, Pilet P, Daculsi G. Macroporous biphasic calcium phosphate ceramics: influence of macropore diameter and macroporosity percentage on bone ingrowth. Biomaterials, 1998, 19(1-3): 133–139

[10] Hutmacher D W. Scaffold design and fabrication technologies for engineering tissues—state of the art and future perspectives. Journal of Biomaterials Science. Polymer Edition, 2001, 12(1): 107–124

[11] Guarino V, Causa F, Ambrosio L. Bioactive scaffolds for bone and ligament tissue. Expert Review of Medical Devices, 2007, 4(3): 405–418

[12] Moroni L, De Wijn J R, Van Blitterswijk C A. Integrating novel technologies to fabricate smart scaffolds. Journal of Biomaterials Science. Polymer Edition, 2008, 19(5): 543–572

[13] Mourino V, Boccaccini A R. Bone tissue engineering therapeutics: controlled drug delivery in three-dimensional scaffolds. Journal of the Royal Society, Interface, 2010, 7(43): 209–227

[14] Baroli B. From natural bone grafts to tissue engineering therapeutics: brainstorming on pharmaceutical formulative requirements and challenges. Journal of Pharmaceutical Sciences, 2009, 98(4): 1317–1375

[15] Habraken W, Wolke J G C, Jansen J A. Ceramic composites as matrices and scaffolds for drug delivery in tissue engineering. Advanced Drug Delivery Reviews, 2007, 59(4-5): 234–248

[16] Lee S H, Shin H. Matrices and scaffolds for delivery of bioactive molecules in bone and cartilage tissue engineering. Advanced Drug Delivery Reviews, 2007, 59(4-5): 339–359

[17] Chung H J, Park T G. Surface engineered and drug releasing pre-fabricated scaffolds for tissue engineering. Advanced Drug Delivery Reviews, 2007, 59(4-5): 249–262

[18] Ginebra M P, Traykova T, Planell J A. Calcium phosphate cements as bone drug delivery systems: a review. Journal of Controlled Release, 2006, 113(2): 102–110

[19] Seeherman H, Wozney J M. Delivery of bone morphogenetic proteins for orthopedic tissue regeneration. Cytokine & Growth Factor Reviews, 2005, 16(3): 329–345

[20] Saltzman W M, Olbricht W L. Building drug delivery into tissue engineering. Nature Reviews. Drug Discovery, 2002, 1(3): 177–186

[21] Stevens M M, George J H. Exploring and engineering the cell surface interface. Science, 2005, 310(5751): 1135–1138

[22] Rezwan K, Chen Q Z, Blaker J J, Boccaccini A R. Biodegradable and bioactive porous polymer/inorganic composite scaffolds for bone tissue engineering. Biomaterials, 2006, 27(18): 3413–3431

[23] Li R, Clark A E, Hench L L. An investigation of bioactive glass powders by sol-gel processing. Journal of Applied Biomaterials, 1991, 2(4): 231–239

[24] Jones J R, Lin S, Yue S, Lee P D, Hanna J V, Smith M E, Newport R J. Bioactive glass scaffolds for bone regeneration and their hierarchical characterisation. Journal of Engineering in Medicine,2010, 224(12): 1373–1387

[25] Qiu D, Martin R A, Knowles J C, Smith M E, Newport R J. A comparative study of the structure of sodium borophosphates made by sol-gel and melt-quench methods. Journal of Non-Crystalline Solids, 2010, 356(9-10): 490–494

[26] Li A, Wang D, Xiang J, Newport R J, Reinholdt M X, Mutin P H, Vantelon D, Bonhomme C, Smith M E, Laurencin D, Qiu D. Insights into new calcium phosphosilicate xerogels using an advanced characterization methodology. Journal of Non-Crystalline Solids, 2011, 357(19-20): 3548–3555

[27] Qiu D, Guerry P, Knowles J C, Smith M E, Newport R J. Formation of functional phosphosilicate gels from phytic acid and tetraethyl orthosilicate. Journal of Sol-Gel Science and Technology, 2008, 48(3): 378–383

[28] Li A, Qiu D. Phytic acid derived bioactive CaO-P₂O₅-SiO₂ gel-glasses. Journal of Materials Science. Materials in Medicine, 2011, 22(12): 2685–2691

[29] Brink M. The influence of alkali and alkaline earths on the working range for bioactive glasses. Journal of Biomedical Materials Research, 1997, 36(1): 109–117

[30] Vitale-Brovarone C, Verne E, Robiglio L, Appendino P, Bassi F, Martinasso G, Muzio G, Canuto R. Development of glass-ceramic scaffolds for bone tissue engineering: characterisation, proliferation of human osteoblasts and nodule formation. Acta Biomaterialia, 2007, 3(2): 199–208

[31] Liu X, Rahaman M N, Fu Q A. Oriented bioactive glass (13-93) scaffolds with controllable pore size by unidirectional freezing of camphene-based suspensions: microstructure and mechanical response. Acta Biomaterialia, 2011, 7(1): 406–416

[32] Vitale-Brovarone C, Di Nunzio S, Bretcanu O, Verne E. Macroporous glass-ceramic materials with bioactive properties. Journal of Materials Science. Materials in Medicine, 2004, 15(3): 209–217

[33] Saboori A, Sheikhi M, Moztarzadeh F, Rabiee M, Hesaraki S, Tahriri M, Nezafati N. Sol-gel preparation, characterisation and in vitro bioactivity of Mg containing bioactive glass. Advances in Applied Ceramics, 2009, 108(3): 155–161

[34] Perez-Pariente J, Balas F, Roman J, Salinas A J, Vallet-Regi M. Influence of composition and surface characteristics on the in vitro bioactivity of SiO₂-CaO-P₂O₅-MgO sol-gel glasses. Journal of Biomedical Materials Research, 1999, 47: 170–175

[35] Salinas A J, Roman J, Vallet-Regi M, Oliveira J M, Correia R N, Fernandes M H. In vitro bioactivity of glass and glass-ceramics of the 3CaO center dot P₂O₅-CaO center dot SiO₂-CaO center dot MgO center dot 2SiO(2) system. Biomaterials, 2000, 21: 251–257

[36] Saboori A, Rabiee M, Mutarzadeh F, Sheikhi M, Tahriri M, Karimi M. Synthesis, characterization and in vitro bioactivity of sol-gel-derived SiO₂-CaO-P₂O₅-MgO bioglass. Mater Sci Eng C Biomim Supramol Syst, 2009, 29(1): 335–340

[37] Jones J R, Ehrenfried L M, Saravanapavan P, Hench L L. Controlling ion release from bioactive glass foam scaffolds with antibacterial properties. Journal of Materials Science. Materials in Medicine, 2006, 17(11): 989–996

[38] Vitale-Brovarone C, Miola M, Alagna C B, Verne E. 3D-glass-ceramic scaffolds with antibacterial properties for bone grafting. Chemical Engineering Journal, 2008, 137(1): 129–136

[39] Courtheoux L, Lao J, Nedelec J M, Jallot E. Controlled bioactivity in zinc-doped sol-gel-derived binary bioactive glasses. Journal of Physical Chemistry C, 2008, 112(35): 13663–13667

[40] Bini M, Grandi S, Capsoni D, Mustarelli P, Saino E, Visai L. SiO₂-P₂O₅-CaO glasses and glass-ceramics with and without ZnO: relationships among composition, microstructure, and bioactivity. Journal of Physical Chemistry C, 2009, 113(20): 8821–8828

[41] Lao J, Jallot E, Nedelec J M. Strontium-delivering glasses with enhanced bioactivity: a new biomaterial for antiosteoporotic applications? Chemistry of Materials, 2008, 20(15): 4969–4973

[42] Nakamura T, Yamamuro T, Higashi S, Kokubo T, Itoo S. A new glass-ceramic for bone-replacement-evaluation of its bonding to bone tissue. Journal of Biomedical Materials Research, 1985, 19(6): 685–698

[43] Ono K, Yamamuro T, Nakamura T, Kokubo T. Mechanical-properties of bone after implantation of apatite wollastonite containing glass ceramic fibrin mixture. Journal of Biomedical Materials Research, 1990, 24(1): 47–63

[44] Kawanabe K, Iida H, Matsusue Y, Nishimatsu H, Kasai R, Nakamura T. A-W glass ceramic as a bone substitute in cemented hip arthroplasty-15 hips followed 2-10 years. Acta Orthopaedica, 1998, 69(3): 237–242

[45] Yang W, Zhou D, Yin G, Zheng C. Research and development of A-W bioactive glass ceramic. Journal of Biomedical Engineer, 2003, 20(3): 541–545 (in Chinese)

[46] Yang W, Zhou D, Yin G, Chen H, Xiao B, Zhang Y. Study on a new type of apatite/wollastonite porous bioactive glass-ceramic. Journal of Biomedical Engineer, 2004, 21: 913–916 (in Chinese)

[47] Shinzato S, Kobayashi M, Mousa W F, Kamimura M, Neo M, Kitamura Y, Kokubo T, Nakamura T. Bioactive polymethyl methacrylate-based bone cement: comparison of glass beads, apatite- and wollastonite-containing glass-ceramic, and hydroxyapatite fillers on mechanical and biological properties. Journal of Biomedical Materials Research, 2000, 51(2): 258–272

[48] Juhasz J A, Best S M, Brooks R, Kawashita M, Miyata N, Kokubo T, Nakamura T, Bonfield W. Mechanical properties of glass-ceramic A-W-polyethylene composites: effect of filler content and particle size. Biomaterials, 2004, 25(6): 949–955

[49] Van de Velde K, Kiekens P. Biopolymers: overview of several properties and consequences on their applications. Polymer Testing, 2002, 21(4): 433–342

[50] Suyatma N E, Tighzert L, Copinet A, Coma V. Effects of hydrophilic plasticizers on mechanical, thermal, and surface properties of chitosan films. Journal of Agricultural and Food Chemistry, 2005, 53(10): 3950–3957

[51] Wang Y, Qiu D, Cosgrove T, Denbow M L. A small-angle neutron scattering and rheology study of the composite of chitosan and gelatin. Colloids and Surfaces B: Biointerfaces, 2009, 70: 254–258

[52] Arvanitoyannis I, Kolokuris I, Nakayama A, Yamamoto N, Aiba S. Physico-chemical studies of chitosan-poly(vinyl alcohol) blends plasticized with sorbitol and sucrose. Carbohydrate Polymers, 1997, 34(1-2): 9–19

[53] Van Vlierberghe S, Dubruel P, Schacht E. Biopolymer-based hydrogels as scaffolds for tissue engineering applications: a review. Biomacromolecules, 2011, 12(5): 1387–1408

[54] Suyatma N E, Copinet A, Tighzert L, Coma V. Mechanical and barrier properties of biodegradable films made from chitosan and poly (lactic acid) blends. Journal of Polymers and the Environment, 2004, 12(1): 1–6

[55] Sarasam A, Madihally S V. Characterization of chitosan-polycaprolactone blends for tissue engineering applications. Biomaterials, 2005, 26(27): 5500–5508

[56] Santos C, Seabra P, Veleirinho B, Delgadillo I, da Silva J A L. Acetylation and molecular mass effects on barrier and mechanical properties of shortfin squid chitosan membranes. European Polymer Journal, 2006, 42(12): 3277–3285

[57] Costa E S, Barbosa-Stancioli E F, Mansur A A P, Vasconcelos W L, Mansur H S. Preparation and characterization of chitosan/poly(vinyl alcohol) chemically crosslinked blends for biomedical applications. Carbohydrate Polymers, 2009, 76(3): 472–481

[58] Khan M, Ferdous S, Mustafa A I. Improvement of physico-mechanical properties of chitosan films by photocuring with acrylic monomers. Journal of Polymers and the Environment, 2005, 13(2): 193–201

[59] Ji B, Gao H. Mechanical properties of nanostructure of biological materials. Journal of the Mechanics and Physics of Solids, 2004, 52(9): 1963–1990

[60] Sionkowska A, Wisniewski M, Skopinska J, Poggi G F, Marsano E, Maxwell C A, Wess T J. Thermal and mechanical properties of UV irradiated collagen/chitosan thin films. Polymer Degradation & Stability, 2006, 91(12): 3026–3032

[61] Saito H, Murabayashi S, Mitamura Y, Taguchi T. Characterization of alkali-treated collagen gels prepared by different crosslinkers. Journal of Materials Science. Materials in Medicine, 2008, 19(3): 1297–1305

[62] Sheu M T, Huang J C, Yeh G C, Ho H O. Characterization of collagen gel solutions and collagen matrices for cell culture. Biomaterials, 2001, 22(13): 1713–1719

[63] Yang L, Van der Werf K O, Fitie C F C, Bennink M L, Dijkstra P J, Feijen J. Mechanical properties of native and cross-linked type I collagen fibrils. Biophysical Journal, 2008, 94(6): 2204–2211

[64] van der Rijt J A J, van der Werf K O, Bennink M L, Dijkstra P J, Feijen J. Micromechanical testing of individual collagen fibrils. Macromolecular Bioscience, 2006, 6(9): 697–702

[65] Sionkowska A, Skopinska-Wisniewska J, Gawron M, Kozlowska J, Planecka A. Chemical and thermal cross-linking of collagen and elastin hydrolysates. International Journal of Biological Macromolecules, 2010, 47(4): 570–577

[66] Nam K, Kimura T, Kishida A. Preparation and characterization of cross-linked collagen-phospholipid polymer hybrid gels. Biomaterials, 2007, 28(1): 1–8

[67] Liu W, Deng C, McLaughlin C R, Fagerholm P, Lagali N S, Heyne B, Scaiano J C, Watsky M A, Kato Y, Munger R, Shinozaki N, Li F F, Griffith M. Collagen-phosphorylcholine interpenetrating network hydrogels as corneal substitutes. Biomaterials, 2009, 30(8): 1551–1559

[68] Yamauchi K, Takeuchi N, Kurimoto A, Tanabe T. Films of collagen crosslinked by S-S bonds: preparation and characterization. Biomaterials, 2001, 22(8): 855–863

[69] Lim L T, Mine Y, Tung M A. Barrier and tensile properties of transglutaminase cross-linked gelatin films as affected by relative humidity, temperature, and glycerol content. Journal of Food Science, 1999, 64(4): 616–622

[70] Usta M, Piech D L, MacCrone R K, Hillig W B. Behavior and properties of neat and filled gelatins. Biomaterials, 2003, 24(1): 165–172

[71] de Carvalho R A, Grosso C R F. Characterization of gelatin based films modified with transglutaminase, glyoxal and formaldehyde. Food Hydrocolloids, 2004, 18(5): 717–722

[72] Cao N, Fu Y, He J. Mechanical properties of gelatin films cross-linked, respectively, by ferulic acid and tannin acid. Food Hydrocolloids, 2007, 21(4): 575–584

[73] Fakirov Z S. Anbar T, Boz B, Bahar I, Evstatiev M, Apostolov A A, Mark J E, Kloczkowski A. Mechanical properties and transition temperatures of cross-linked oriented gelatin: 1.Static and dynamic mechanical properties of cross-linked gelatin. Colloid & Polymer Science, 1996, 274: 334–341

[74] Santin M, Huang S J, Iannace S, Ambrosio L, Nicolais L, Peluso G. Synthesis and characterization of a new interpenetrated poly(2-hydroxyethylmethacrylate)-gelatin composite polymer. Biomaterials, 1996, 17(15): 1459–1467

[75] Vemuri S. A screening technique to study the mechanical strength of gelatin formulations. Drug Development and Industrial Pharmacy, 2000, 26(10): 1115–1120

[76] Bigi A, Bracci B, Cojazzi G, Panzavolta S, Roveri N. Drawn gelatin films with improved mechanical properties. Biomaterials, 1998, 19(24): 2335–2340

[77] Bigi A, Cojazzi G, Panzavolta S, Rubini K, Roveri N. Mechanical and thermal properties of gelatin films at different degrees of glutaraldehyde crosslinking. Biomaterials, 2001, 22(8): 763–768

[78] Yakimets I, Wellner N, Smith A C, Wilson R H, Farhat I, Mitchell J. Mechanical properties with respect to water content of gelatin films in glassy state. Polymer, 2005, 46(26): 12577–12585

[79] Lee K Y, Shim J, Lee H G. Mechanical properties of gellan and gelatin composite films. Carbohydrate Polymers, 2004, 56(2): 251–254

[80] Bigi A, Panzavolta S, Rubini K. Relationship between triple-helix content and mechanical properties of gelatin films. Biomaterials, 2004, 25(25): 5675–5680

[81] Gómez-Guillén M C, Perez-Mateos M, Gomez-Estaca J, Lopez-Caballero E, Gimenez B, Montero P. Fish gelatin: a renewable material for developing active biodegradable films. Trends in Food Science & Technology, 2009, 20(1): 3–16

[82] Arvanitoyannis I, Nakayama A, Aiba S I. Edible films made from hydroxypropyl starch and gelatin and plasticized by polyols and water. Carbohydrate Polymers, 1998, 36(2-3): 105–119

[83] Arvanitoyannis I S, Nakayama A, Aiba S I. Chitosan and gelatin based edible films: state diagrams, mechanical and permeation properties. Carbohydrate Polymers, 1998, 37(4): 371–382

[84] Park J W, Scott Whiteside W, Cho S Y. Mechanical and water vapor barrier properties of extruded and heat-pressed gelatin films. LWT- Food Science and Technology, 2008, 41(4): 692–700

[85] Koob T J, Hernandez D J. Mechanical and thermal properties of novel polymerized NDGA-gelatin hydrogels. Biomaterials, 2003, 24(7): 1285–1292

[86] Karageorgiou V, Kaplan D. Porosity of 3D biornaterial scaffolds and osteogenesis. Biomaterials, 2005, 26(27): 5474–5491

[87] Jones J R, Ehrenfried L M, Hench L L. Optimising bioactive glass scaffolds for bone tissue engineering. Biomaterials, 2006, 27(7): 964–973

[88] FitzGerald V, Martin R A, Jones J R, Qiu D, Wetherall K M, Moss R M, Newport R J. Bioactive glass sol-gel foam scaffolds: Evolution of nanoporosity during processing and in situ monitoring of apatite layer formation using small- and wide-angle X-ray scattering. Journal of Biomedical Materials Research. Part A, 2009, 91A(1): 76–83

[89] Wu Z Y, Hill R G, Yue S, Nightingale D, Lee P D, Jones J R. Melt-derived bioactive glass scaffolds produced by a gel-cast foaming technique. Acta Biomaterialia, 2011, 7(4): 1807–1816

[90] Chen Q Z Z, Thompson I D, Boccaccini A R. 45S5 Bioglass®-derived glass-ceramic scaffolds for bone tissue engineering. Biomaterials, 2006, 27(11): 2414–2425

[91] Liu X, Huang W H, Fu H L, Yao A H, Wang D P, Pan H B, Lu W W. Bioactive borosilicate glass scaffolds: improvement on the strength of glass-based scaffolds for tissue engineering. Journal of Materials Science. Materials in Medicine, 2009, 20(1): 365–372

[92] Xue M, Feng D G, Li G D, Yang W Z, Zhou D L. Preparation of porous apatite-wollastonite bioactive glass ceramic (AW-GC) by dipping with polymer foams. Chinese Journal of Inorganic Chemistry, 2007, 23: 708–712

[93] Cao B, Zhou D, Xue M, Li G, Yang W, Long Q, Ji L. Study on surface modification of porous apatite-wollastonite bioactive glass ceramic scaffold. Applied Surface Science, 2008, 255(2): 505–508

[94] Baino F, Verne E, Vitale-Brovarone C. 3-D high-strength glass-ceramic scaffolds containing fluoroapatite for load-bearing bone portions replacement. Materials Science and Engineering: C, 2009, 29(6): 2055–2062

[95] Bellucci D, Cannillo V, Sola A, Chiellini F, Gazzarri M, Migone C. Macroporous Bioglass®-derived scaffolds for bone tissue regeneration. Ceramics International, 2011, 37(5): 1575–1585

[96] Yan H, Zhang K, Blanford C F, Francis L F, Stein A. In vitro hydroxycarbonate apatite mineralization of CaO-SiO₂ sol-gel glasses with a three-dimensionally ordered macroporous structure. Chemistry of Materials, 2001, 13(4): 1374–1382

[97] Yan P H, Wang J Q, Ou J F, Li Z P, Lei Z Q, Yang S R. Synthesis and characterization of three-dimensional ordered mesoporous-macroporous bioactive glass. Materials Letters, 2010, 64(22): 2544–2547

[98] Wei G F, Yan X X, Yi J, Zhao L Z, Zhou L, Wang Y H, Yu C Z. Synthesis and in-vitro bioactivity of mesoporous bioactive glasses with tunable macropores. Microporous and Mesoporous Materials, 2011, 143(1): 157–165

[99] Hajiali H, Karbasi S, Hosseinalipour M, Rezaie H R. Preparation of a novel biodegradable nanocomposite scaffold based on poly (3-hydroxybutyrate)/bioglass nanoparticles for bone tissue engineering. Journal of Materials Science, 2010, 21(7): 2125–2133

[100] Ryszkowska J L, Auguscik M, Sheikh A, Boccaccini A R. Biodegradable polyurethane composite scaffolds containing Bioglass® for bone tissue engineering. Composites Science and Technology, 2010, 70(13): 1894–1908

[101] Mozafari M, Moztarzadeh F, Rabiee M, Azami M, Maleknia S, Tahriri M, Moztarzadeh Z, Nezafati N. Development of macroporous nanocomposite scaffolds of gelatin/bioactive glass prepared through layer solvent casting combined with lamination technique for bone tissue engineering. Ceramics International, 2010, 36(8): 2431–2439

[102] Hong Z K, Reis R L, Mano J F. Preparation and in vitro characterization of scaffolds of poly(L-lactic acid) containing bioactive glass ceramic nanoparticles. Acta Biomaterialia, 2008, 4(5): 1297–1306

[103] Barroca N, Daniel-da-Silva A L, Vilarinho P M, Fernandes M H V. Tailoring the morphology of high molecular weight PLLA scaffolds through bioglass addition. Acta Biomaterialia, 2010, 6(9): 3611–3620

[104] Fabbri P, Cannillo V, Sola A, Dorigato A, Chiellini F. Highly porous polycaprolactone-45S5 Bioglass® scaffolds for bone tissue engineering. Composites Science and Technology, 2010, 70(13): 1869–1878

[105] Minaberry Y, Jobbagy M. Macroporous bioglass scaffolds prepared by coupling sol-gel with freeze drying. Chemistry of Materials, 2011, 23(9): 2327–2332

[106] Doiphode N D, Huang T S, Leu M C, Rahaman M N, Day D E. Freeze extrusion fabrication of 13-93 bioactive glass scaffolds for bone repair. Journal of Materials Science. Materials in Medicine, 2011, 22(3): 515–523

[107] Garcia A, Izquierdo-Barba I, Colilla M, de Laorden C L, Vallet-Regí M. Lopez de laorden C, Vallet-Regi M. Preparation of 3-D scaffolds in the SiO₂-P₂O₅ system with tailored hierarchical meso-macroporosity. Acta Biomaterialia, 2011, 7(3): 1265–1273

[108] Yun H S, Kim S E, Park E K. Bioactive glass-poly(epsilon-caprolactone) composite scaffolds with 3 dimensionally hierarchical pore networks. Materials Science and Engineering: C, 2011, 31(2): 198–205

[109] Valliant E M, Jones J R. Softening bioactive glass for bone regeneration: sol-gel hybrid materials. Soft Matter, 2011, 7(11): 5083–5095

[110] Mahony O, Tsigkou O, Ionescu C, Minelli C, Ling L, Hanly R, Smith M E, Stevens M M, Jones J R. Silica-gelatin hybrids with tailorable degradation and mechanical properties for tissue regeneration. Advanced Functional Materials, 2010, 20(22): 3835–3845

[111] Pereira M M, Jones J R, Orefice R L, Hench L L. Preparation of bioactive glass-polyvinyl alcohol hybrid foams by the sol-gel method. Journal of Materials Science. 2005, 16(11): 1045–1050

[112] Costa H S, Rocha M F, Andrade G I, Barbosa-Stancioli E F, Pereira M M, Orefice R L, Vasconcelos W L, Mansur H S. Sol-gel derived composite from bioactive glass-polyvinyl alcohol. Journal of Materials Science, 2008, 43(2): 494–502

[113] Costa H S, Stancioli E F B, Pereira M M, Orefice R L, Mansur H S. Synthesis, neutralization and blocking procedures of organic/inorganic hybrid scaffolds for bone tissue engineering applications. Journal of Materials Science, 2009, 20(2): 529–535

[114] de Oliveira A A R, Ciminelli V, Dantas M S S, Mansur H S, Pereira M M. Acid character control of bioactive glass/polyvinyl alcohol hybrid foams produced by sol-gel. Journal of Sol-Gel Science and Technology, 2008, 47(3): 335–346

[115] Costa H S, Mansur A A P, Pereira M M, Mansur H S. Engineered hybrid scaffolds of poly(vinyl alcohol)/bioactive glass for potential bone engineering applications: synthesis, characterization, cytocompatibility, and degradation. Journal of Nanomaterials, 2012, 2012: 1–16

[116] Lin S, Ionescu C, Pike K J, Smith M E, Jones J R. Nanostructure evolution and calcium distribution in sol-gel derived bioactive glass. Journal of Materials Chemistry, 2009, 19(9): 1276–1282

Acknowledgments

This project was Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.

RIGHTS & PERMISSIONS

2014 Higher Education Press and Springer-Verlag Berlin Heidelberg