Additive manufacturing of photosensitive Hydrogels for tissue engineering applications

BioNanoMaterials

Volumn 15, Issue 3-4, 2014, Pages 49-70

  Qin, Xiao Hua ^a   Ovsianikov, Aleksandr ^a   Stampfl, Jürgen ^a   Liska, Robert ^a  

^a VIENNA UNIVERSITY OF TECHNOLOGY   (Austria)

Author keywords

Additive manufacturing technologies (AMT); Biofabrication; Hydrogels, photopolymerization; Tissue engineering; Two photon lithography

Indexed keywords

EID: 84947557967     PISSN: 21930651     EISSN: 2193066X     Source Type: Journal    
DOI: 10.1515/bnm-2014-0008     Document Type: Review

References (129)

1. Mooney D, Langer R. Engineering biomaterials for tissue engineering: the 10-100 micron size scale. In: The biomedical engineering handbook, 2nd edition. Bronzino: CRC Press LLC, 2000.
2. Ratner BD, Bryant SJ. Biomaterials: where we have been and where we are going. Annu Rev Biomed Eng 2004;6:41-75.
3. Hofmann D, Entrialgo-Castano M, Kratz K, Lendlein A. Knowledgebased approach towards hydrolytic degradation of polymer-based biomaterials. Adv Mater 2009;21:3237-45.
4. Atala A, Kasper FK, Mikos AG. Engineering complex tissues. Sci Transl Med 2012;4:160rv12.
5. Mikos AG, Herring SW, Ochareon P, Elisseeff J, Lu HH, Kandel R, et al. Engineering complex tissues. Tissue Eng 2006;12:3307-39.
6. Dvir T, Timko BP, Kohane DS, Langer R. Nanotechnological strategies for engineering complex tissues. Nat Nanotechnol 2011;6:13-22.
7. Tsang VL, Bhatia SN. Three-dimensional tissue fabrication. Adv Drug Deliv Rev 2004;56:1635-47.
8. Rice JJ, Martino MM, De Laporte L, Tortelli F, Briquez PS, Hubbell JA. Engineering the regenerative microenvironment with biomaterials. Adv Healthc Mater 2013;2:57-71.
9. Tibbitt MW, Anseth KS. Dynamic microenvironments: the fourth dimension. Sci Transl Med 2012;4:160ps24.
10. Tibbitt MW, Anseth KS. Hydrogels as extracellular matrix mimics for 3D cell culture. Biotechnol Bioeng 2009;103:655-63.
11. Ovsianikov A, Mironov V, Stampfl J, Liska R. Engineering 3D cell-culture matrices: multiphoton processing technologies for biological & tissue engineering applications. Expert Rev Med Devices 2012;9:613-3.
12. Cushing MC, Anseth KS. Hydrogel cell cultures. Science 2007;316:1133-4.
13. Lu SX, Anseth KS. Release behavior of high molecular weight solutes from poly (ethylene glycol)-based degradable networks. Macromolecules 2000;33:2509-15.
14. Discher DE, Mooney DJ, Zandstra PW. Growth factors, matrices, and forces combine and control stem cells. Science 2009;324:1673-7.
15. Discher DE, Janmey P, Wang YL. Tissue cells feel and respond to the stiffness of their substrate. Science 2005;310:1139-43.
16. Drury JL, Mooney DJ. Hydrogels for tissue engineering: scaffold design variables and applications. Biomaterials 2003;24:4337-51.
17. Nguyen KT, West JL. Photopolymerizable hydrogels for tissue engineering applications. Biomaterials 2002;23:4307-14.
18. Nicodemus GD, Bryant SJ. Cell encapsulation in biodegradable hydrogels for tissue engineering applications. Tissue Eng Part B Rev 2008;14:149-65.
19. Liska R, Schwager F, Maier C, Cano-Vives R, Stampfl J. Water-soluble photopolymers for rapid prototyping of cellular materials. J Appl Polym Sci 2005;97:2286-98.
20. Zorlutuna P, Jeong JH, Kong H, Bashir R. Stereolithographybased hydrogel microenvironments to examine cellular interactions. Adv Funct Mater 2011;21:3642-51.
21. Bryant SJ, Cuy JL, Hauch KD, Ratner BD. Photo-patterning of porous hydrogels for tissue engineering. Biomaterials 2007;28:2978-86.
22. Ullrich G, Burtscher P, Salz U, Moszner N, Liska R. Phenylglycine derivatives as coinitiators for the radical photopolymerization of acidic aqueous formulations. J Polym Sci Part A: Polym Chem 2006;44:115-25.
23. Lu Y, Hasegawa F, Goto T, Ohkuma S, Fukuhara S, Kawazu Y, et al. Highly sensitive measurement in two-photon absorption cross section and investigation of the mechanism of two-photoninduced polymerization. J Lumin 2004;110:1-10.
24. Bryant SJ, Nuttelman CR, KS. Cytocompatibility of UV and visible light photoinitiating systems on cultured NIH/3T3 fibroblasts in vitro. J Biomater Sci Polym Ed 2000;11:439-57.
25. Orellana B, Rufs AM, Encinas MV, Previtali CM, Bertolotti S. The photoinitiation mechanism of vinyl polymerization by riboflavin/triethanolamine in aqueous medium. Macromolecules 1999;32:6570-3.
26. Bahney CS, Lujan TL, Hsu CW, Bottlang M, West JL, Johnstone B. Visible light photoinitiation of mesenchymal stem cell-laden bioresponsive hydrogels. Eur Cells and Materials 2011;22:43-55.
27. Woo HY, Liu B, Kohler B, Korystov D, Mikhailovsky A, Bazan GC, et al. Solvent effects on the two-photon absorption of distyrylbenzene chromophores. J Am Chem Soc 2005;127:14721-9.
28. Li Z, Torgersen J, Ajami A, Muhleder S, Qin X, Husinsky W, et al. Initiation efficiency and cytotoxicity of novel water-soluble two-photon photoinitiators for direct 3D microfabrication of hydrogels. RSC Advances 2013;3:15939-46.
29. Williams CG, Malik AN, Kim TK, Manson PN, Elisseeff JH. Variable cytocompatibility of six cell lines with photoinitiators used for polymerizing hydrogels and cell encapsulation. Biomaterials 2005;26:1211-8.
30. Sawhney AS, Pathak CP, Hubbell JA. Interfacial photopolymerization of poly (ethylene glycol)-based hydrogels upon alginatepoly (l-lysine) microcapsules for enhanced biocompatibility. Biomaterials 1993;14:1008-16.
31. Fairbanks BD, Schwartz MP, Bowman CN, Anseth KS. Photoinitiated polymerization of PEG-diacrylate with lithium phenyl-2, 4, 6-trimethylbenzoylphosphinate: polymerization rate and cytocompatibility. Biomaterials 2009;30:6702-7.
32. Torgersen J, Ovsianikov A, Mironov V, Pucher N, Qin X, Li Z, et al. Photo-sensitive hydrogels for three-dimensional laser microfabrication in the presence of whole organisms. J Biomed Opt 2012;17:105008.
33. Husar B, Liska R. Vinyl carbonates, vinyl carbamates, and related monomers: synthesis, polymerization, and application. Chem Soc Rev 2012;41:2395-405.
34. Moszner N, Hirt T. New polymer-chemical developments in clinical dental polymer materials: Enamel-dentin adhesives and restorative composites. J Polym Sci, Part A: Polym Chem 2012;50:4369-402.
35. Heller C, Schwentenwein M, Russmueller G, Varga F, Stampfl J, Liska R, et al. Vinyl esters: Low cytotoxicity monomers for the fabrication of biocompatible 3D scaffolds by lithography based additive manufacturing. J Polym Sci, Part A: Polym Chem 2009;47:6941-54.
36. Lee TY, Kaung W, Jönsson ES, Lowery K, Guymon CA, Hoyle CE, et al. Synthesis and photopolymerization of novel multifunctional vinyl esters. J Polym Sci, Part A: Polym Chem 2004;42:4424-36.
37. Mautner A, Qin X, Wutzel H, Ligon SC, Kapeller B, Moser D, et al. Thiol-ene photopolymerization for efficient curing of vinyl esters. J Polym Sci, Part A: Polym Chem 2013;51:203-12.
38. Esfandiari P, Ligon SC, Lagref JJ, Frantz R, Cherkaoui Z, Liska R, et al. Efficient stabilization of thiol-ene formulations in radical photopolymerization. J Polym Sci, Part A: Polym Chem 2013;51:4261-6.
39. Iha RK, Wooley KL, Nystrom AM, Burke DJ, Kade MJ, Hawker CJ, et al. Applications of orthogonal "click" chemistries in the synthesis of functional soft materials. Chem Rev 2009;109:5620-86.
40. Malkoch M, Vestberg R, Gupta N, Mespouille L, Dubois P, Mason AF, et al. Synthesis of well-defined hydrogel networks using click chemistry. Chem Commun 2006;2774-6.
41. Ossipov DA, Hilborn Jn. Poly (vinyl alcohol)-based hydrogels formed by click chemistry. Macromolecules 2006;39:1709-18.
42. Crescenzi V, Cornelio L, Di Meo C, Nardecchia S, Lamanna R. Novel hydrogels via click chemistry: synthesis and potential biomedical applications. Biomacromolecules 2007;8:1844-50.
43. Adzima BJ, Tao Y, Kloxin CJ, DeForest CA, Anseth KS, Bowman CN. Spatial and temporal control of the alkyne-azide cycloaddition by photoinitiated Cu (II) reduction. Nat Chem 2011;3:256-9.
44. Alge DL, Azagarsamy MA, Donohue DF, Anseth KS. Synthetically tractable click hydrogels for three-dimensional cell culture formed using tetrazine-norbornene chemistry. Biomacromolecules 2013;14:949-53.
45. Grover GN, Lam J, Nguyen TH, Segura T, Maynard HD. Biocompatible hydrogels by oxime click chemistry. Biomacromolecules 2012;13:3013-7.
46. Fairbanks BD, Schwartz MP, Halevi AE, Nuttelman CR, Bowman CN, Anseth KS. A versatile synthetic extracellular matrix mimic via thiol-norbornene photopolymerization. Adv Mater 2009;21:5005-10.
47. Hoyle CE, Bowman CN. Thiol-ene click chemistry. Angew Chem Int Ed Engl 2010;49:1540-73.
48. Hoyle CE, Lee TY, Roper T. Thiol-enes: chemistry of the past with promise for the future. J Polym Sci, Part A: Polym Chem 2004;42:5301-38.
49. Kirschner CM, Brennan AB. Bio-inspired antifouling strategies. Ann Rev Mater Res 2012;42:211-29.
50. Kirschner CM, Anseth KS. Hydrogels in healthcare: from static to dynamic material microenvironments. Acta Materialia 2013;61:931-44.
51. Weber LM, Lopez CG, Anseth KS. Effects of PEG hydrogel crosslinking density on protein diffusion and encapsulated islet survival and function. J Biomed Mater Res A 2009;90:720-9.
52. Sawhney AS, Pathak CP, Hubbell JA. Bioerodible hydrogels based on photopolymerized poly (ethylene glycol)-co-poly (. alpha.-hydroxy acid) diacrylate macromers. Macromolecules 1993;26:581-7.
53. Bryant SJ, Bender RJ, Durand KL, Anseth KS. Encapsulating chondrocytes in degrading PEG hydrogels with high modulus: engineering gel structural changes to facilitate cartilaginous tissue production. Biotechnol Bioeng 2004;86:747-55.
54. Metters AT, Anseth KS, Bowman CN. Fundamental studies of a novel, biodegradable PEG-b-PLA hydrogel. Polymer 2000;41:3993-4004.
55. McCall JD, Anseth KS. Thiol-ene photopolymerizations provide a facile method to encapsulate proteins and maintain their bioactivity. Biomacromolecules 2012;13:2410-7.
56. Cascone MG, Laus M, Ricci D, Sbarbati Del Guerra R. Evaluation of poly (vinyl alcohol) hydrogels as a component of hybrid artificial tissues. J Mater Sci Mater Med 1995;6:71-5.
57. Nuttelman CR, Mortisen DJ, Henry SM, Anseth KS. Attachment of fibronectin to poly (vinyl alcohol) hydrogels promotes NIH3T3 cell adhesion, proliferation, and migration. J Biomed Mater Res 2001;57:217-23.
58. Orienti Trere R, Zecchi V. Hydrogels formed by cross-linked polyvinylalcohol as colon-specific drug delivery systems. Drug Dev Ind Pharm 2001;27:877-84.
59. Martens P, Holland T, Anseth KS. Synthesis and characterization of degradable hydrogels formed from acrylate modified poly (vinyl alcohol) macromers. Polymer 2002;43:6093-100.
60. Martens PJ, Bryant SJ, Anseth KS. Tailoring the degradation of hydrogels formed from multivinyl poly (ethylene glycol) and poly (vinyl alcohol) macromers for cartilage tissue engineering. Biomacromolecules 2003;4:283-92.
61. Schmedlen RH, Masters KS, West JL. Photocrosslinkable polyvinyl alcohol hydrogels that can be modified with cell adhesion peptides for use in tissue engineering. Biomaterials 2002;23:4325-32.
62. Thomas HB. The role of ECM proteins and protein fragments in guiding cell behavior in regenerative medicine. Biomaterials 2011;32:4211-4.
63. Jeon O, Bouhadir KH, Mansour JM, Alsberg E. Photocrosslinked alginate hydrogels with tunable biodegradation rates and mechanical properties. Biomaterials 2009;30:2724-34.
64. Kong HJ, Smith MK, Mooney DJ. Designing alginate hydrogels to maintain viability of immobilized cells. Biomaterials 2003;24:4023-9.
65. Lee KY, Rowley JA, Eiselt P, Moy EM, Bouhadir KH, Mooney DJ. Controlling mechanical and swelling properties of alginate hydrogels independently by cross-linker type and cross-linking density. Macromolecules 2000;33:4291-4.
66. Garcia-Fuentes M, Alonso MJ. Chitosan-based drug nanocarriers: Where do we stand? J Control Release 2012;161:496-504.
67. Kim YK, Jiang HL, Choi YJ, Park IK, Cho MH, Cho CS. Polymeric nanoparticles of chitosan derivatives as dna and sirna carriers. Adv Polym Sci 2011;243:1-21.
68. Abrahams JM, Chen W. Modified chitosan for vascular embolization US 20070031468: Patent 2007:1-13.
69. Shoulders MD, Raines RT. Collagen structure and stability. Annu Rev Biochem 2009;78:929-58.
70. Leitinger B, Hohenester E. Mammalian collagen receptors. Matrix Biol 2007;26:146-55.
71. Schoof H, Apel J, Heschel I, Rau G. Control of pore structure and size in freeze-dried collagen sponges. J Biomed Mater Res 2001;58:352-7.
72. Lee CR, Grodzinsky AJ, Spector M. The effects of cross-linking of collagen-glycosaminoglycan scaffolds on compressive stiffness, chondrocyte-mediated contraction, proliferation and biosynthesis. Biomaterials 2001;22:3145-54.
73. Park S-N, Park J-C, Kim HO, Song MJ, Suh H. Characterization of porous collagen/hyaluronic acid scaffold modified by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide cross-linking. Biomaterials 2002;23:1205-12.
74. Young S, Wong M, Tabata Y, Mikos AG. Gelatin as a delivery vehicle for the controlled release of bioactive molecules. J Control Release 2005;109:256-74.
75. Holland TA, Tabata Y, Mikos AG. Dual growth factor delivery from degradable oligo (poly (ethylene glycol) fumarate) hydrogel scaffolds for cartilage tissue engineering. J Control Release 2005;101:111-25.
76. Van den Bulcke AI, Bogdanov B, De Rooze N, Schacht EH, Cornelissen M, Berghmans H. Structural and rheological properties of methacrylamide modified gelatin hydrogels. Biomacromolecules 2000;1:31-8.
77. Nichol JW, Koshy ST, Bae H, Hwang CM, Yamanlar S, Khademhosseini A. Cell-laden microengineered gelatin methacrylate hydrogels. Biomaterials 2010;31:5536-44.
78. Levett PA, Melchels FP, Schrobback K, Hutmacher DW, Malda J, et al. A biomimetic extracellular matrix for cartilage tissue engineering centered on photocurable gelatin, hyaluronic acid and chondroitin sulfate. Acta Biomater 2014;10:214-23.
79. Levett PA, Melchels FP, Schrobback K, Hutmacher DW, Malda J, et al. Chondrocyte redifferentiation and construct mechanical property development in single-component photocrosslinkable hydrogels. J Biomed Mater Res Part A 2014;102:2544-53.
80. Ovsianikov A, Deiwick A, Van Vlierberghe S, Dubruel P, Möller L, Dräger G, et al. Laser fabrication of three-dimensional CAD scaffolds from photosensitive gelatin for applications in tissue engineering. Biomacromolecules 2011;12:851-8.
81. Qin X-H, Torgersen J, Saf R, Mühleder S, Pucher N, Ligon SC, et al. Three-dimensional microfabrication of protein hydrogels via two-photon-excited thiol-vinyl ester photopolymerization. J Polym Sci, Part A: Polym Chem 2013;51:4799-810.
82. Liu Y, Ahmad S, Shu XZ, Sanders RK, Kopesec SA, Prestwich GD. et al. Accelerated repair of cortical bone defects using a synthetic extracellular matrix to deliver human demineralized bone matrix. J Orth Res 2006;24:1454-62.
83. Duflo S, Thibeault SL, Li WH, Shu XZ, Prestwich GD. Vocal fold tissue repair in vivo using a synthetic extracellular matrix. Tissue Eng 2006;12:2171-80.
84. Shu XZ, Liu YC, Luo Y, Roberts MC, Prestwich GD. Disulfide crosslinked hyaluronan hydrogels. Biomacromolecules 2002;3:1304-11.
85. Burdick JA, Prestwich GD. Hyaluronic acid hydrogels for biomedical applications. Adv Mater 2011;23:41-56.
86. Zheng Shu X, Liu Y, Palumbo FS, Luo Y, Prestwich GD. In situ crosslinkable hyaluronan hydrogels for tissue engineering. Biomaterials 2004;25:1339-48.
87. Smeds KA, Pfister-Serres A, Miki D, Dastgheib K, Inoue M, Hatchell DL, et al. Photocrosslinkable polysaccharides for in situ hydrogel formation. J Biomed Mater Res 2001;54:115-21.
88. Baier Leach J, Bivens KA, Patrick CW Jr., Schmidt CE. Photocrosslinked hyaluronic acid hydrogels: natural, biodegradable tissue engineering scaffolds. Biotechnol Bioeng 2003;82:578-89.
89. Khademhosseini A, Eng G, Yeh J, Fukuda J, Blumling J, Langer R, et al. Micromolding of photocrosslinkable hyaluronic acid for cell encapsulation and entrapment. J Biomed Mater Res Part A 2006;79A:522-32.
90. Khetan S, Katz JS, Burdick JA. Sequential crosslinking to control cellular spreading in 3-dimensional hydrogels. Soft Matter 2009;5:1601-6.
91. Kade MJ, Burke DJ, Hawker CJ. The power of thiol-ene chemistry. J Polym Sci, Part A: Polym Chem 2010;48:743-50.
92. Qin X-H, Gruber P, Markovic M, Plochberger B, Klotzsch E, Stampfl J, et al. Enzymatic synthesis of hyaluronic acid vinyl esters for two-photon microfabrication of biocompatible and biodegradable hydrogel constructs. Polym Chem 2014;5:6523-33.
93. Brauker JH, Carr-Brendel VE, Martinson LA, Crudele J, Johnston WD, Johnson RC. Neovascularization of synthetic membranes directed by membrane microarchitecture. J Biomed Mater Res 1995;29:1517-24.
94. Chirila TV. An overview of the development of artificial corneas with porous skirts and the use of PHEMA for such an application. Biomaterials 2001;22:3311-7.
95. Billiet T, Vandenhaute M, Schelfhout J, Van Vlierberghe S, Dubruel P. A review of trends and limitations in hydrogel-rapid prototyping for tissue engineering. Biomaterials 2012;33:6020-41.
96. Griffith LG, Swartz MA. Capturing complex 3D tissue physiology in vitro. Nat Rev Mol Cell Biol 2006;7:211-24.
97. Chen CS, Mrksich M, Huang S, Whitesides GM, Ingber DE. Geometric control of cell life and death. Science 1997;276:1425-8.
98. Tsang VL, Chen AA, Cho LM, Jadin KD, Sah RL, DeLong S, et al. Fabrication of 3D hepatic tissues by additive photopatterning of cellular hydrogels. FASEB J 2007;21:790-801.
99. Liu V, Bhatia S. Three-dimensional photopatterning of hydrogels containing living cells. Biomed Microdevices 2002;4:257-66.
100. Marklein RA, Burdick JA. Spatially controlled hydrogel mechanics to modulate stem cell interactions. Soft Matter 2010;6:136-43.
101. Nemir S, Hayenga HN, West JL. PEGDA hydrogels with patterned elasticity: novel tools for the study of cell response to substrate rigidity. Biotechnol Bioeng 2010;105:636-44.
102. Seidi A, Ramalingam M, Elloumi-Hannachi I, Ostrovidov S, Khademhosseini A. Gradient biomaterials for soft-to-hard interface tissue engineering. Acta Biomater 2011;7:1441-51.
103. Du Y, Shim J, Vidula M, Hancock MJ, Lo E, Chung BG, et al. Rapid generation of spatially and temporally controllable longrange concentration gradients in a microfluidic device. Lab Chip 2009;9:761-7.
104. Khetan S, Burdick JA. Patterning network structure to spatially control cellular remodeling and stem cell fate within 3-dimensional hydrogels. Biomaterials 2010;31:8228-34.
105. Lu Y, Mapili G, Suhali G, Chen S, Roy K. A digital micro-mirror device-based system for the microfabrication of complex, spatially patterned tissue engineering scaffolds. J Biomed Mater Res Part A 2006;77A:396-405.
106. Massia SP, Hubbell JA. An RGD spacing of 440 nm is sufficient for integrin alpha V beta 3-mediated fibroblast spreading and 140 nm for focal contact and stress fiber formation. J Cell Biol 1991;114:1089-100.
107. Hsieh TM, Benjamin Ng CW, Narayanan K, Wan AC, Ying JY. Three-dimensional microstructured tissue scaffolds fabricated by two-photon laser scanning photolithography. Biomaterials 2010;31:7648-52.
108. Ovsianikov A, Gruene M, Pflaum M, Koch L, Maiorana F, Wilhelmi M, et al. Laser printing of cells into 3D scaffolds. Biofabrication 2010;2:014104.
109. LaFratta CN, Fourkas JT, Baldacchini T, Farrer RA. Multiphoton fabrication. Angew Chem Int Ed Engl 2007;46:6238-58.
110. Wu SH, Serbin J, Gu M. Two-photon polymerisation for three-dimensional micro-fabrication. J Photochem Photobiol A Chem 2006;181:1-11.
111. Perry JW, Cumpston BH, Ananthavel SP, Barlow S, Dyer DL, Ehrlich JE, et al. Two-photon polymerization initiators for three-dimensional optical data storage and microfabrication. Nature 1999;398:51-4.
112. Nguyen DH, Stapleton SC, Yang MT, Cha SS, Choi CK, Galie PA, et al. Biomimetic model to reconstitute angiogenic sprouting morphogenesis in vitro. Proc Natl Acad Sci USA 2013;110:6712-7.
113. Bae H, Puranik AS, Gauvin R, Edalat F, Carrillo-Conde B, Peppas NA, et al. Building vascular networks. Sci Transl Med 2012;4:160ps23.
114. Saik JE, McHale MK, West JL. Biofunctional materials for directing vascular development. Curr Vasc Pharmacol 2012;10:331-41.
115. Ehrbar M, Djonov VG, Schnell C, Tschanz SA, Martiny-Baron G, Schenk U, et al. Cell-demanded liberation of VEGF121 from fibrin implants induces local and controlled blood vessel growth. Circ Res 2004;94:1124-32.
116. Silva AK, Richard C, Bessodes M, Scherman D, Merten O-W. Growth factor delivery approaches in hydrogels. Biomacromolecules 2008;10:9-18.
117. Zisch AH, Lutolf MP, Ehrbar M, Raeber GP, Rizzi SC, Davies N, et al. Cell-demanded release of VEGF from synthetic, biointeractive cell ingrowth matrices for vascularized tissue growth. FASEB J 2003;17:2260-2.
118. Muehleder S, Ovsianikov A, Zipperle J, Redl H, Holnthoner W. Connections matter: channeled hydrogels to improve vascularization. Front Bioeng Biotechnol 2014;2:52.
119. Hahn MS, Miller JS, West JL. Laser scanning lithography for surface micropatterning on hydrogels. Adv Mater 2005;17:2939-42.
120. Hahn MS, Miller JS, West JL. Three-dimensional biochemical and biomechanical patterning of hydrogels for guiding cell behavior. Adv Mater 2006;18:2679-84.
121. Wylie RG, Ahsan S, Aizawa Y, Maxwell KL, Morshead CM, Shoichet MS. Spatially controlled simultaneous patterning of multiple growth factors in three-dimensional hydrogels. Nat Mater 2011;10:799-806.
122. Luo Y, Shoichet MS. A photolabile hydrogel for guided three-dimensional cell growth and migration. Nat Mater 2004;3:249-53.
123. Ovsianikov A, Li Z, Torgersen J, Stampfl J, Liska R. Selective functionalization of 3D matrices via multiphoton grafting and subsequent click chemistry. Adv Funct Mater 2012;22:3429-33.
124. Li Z, Ajami A, Stankevièius E, Husinsky W, Raèiukaitis G, Stampfl J, et al. 3D photografting with aromatic azides: A comparison between three-photon and two-photon case. Opt Mater 2013;35:1846-51.
125. Li Z, Stankevicius E, Ajami A, Raciukaitis G, Husinsky W, Ovsianikov A, et al. 3D alkyne-azide cycloaddition: spatiotemporally controlled by combination of aryl azide photochemistry and two-photon grafting. Chem Commun (Camb) 2013;49:7635-7.
126. Jhaveri SJ, McMullen JD, Sijbesma R, Tan LS, Zipfel W, Ober CK. Direct three-dimensional microfabrication of hydrogels via two-photon lithography in aqueous solution. Chem Mater 2009;21:2003-6.
127. Kapyla E, Sedlacik T, Aydogan DB, Viitanen J, Rypacek F, Kellomäki M. Direct laser writing of synthetic poly (amino acid) hydrogels and poly (ethylene glycol) diacrylates by two-photon polymerization. Mater Sci Eng C Mater Biol Appl 2014;43:280-9.
128. Husár, B, Hatzenbichler M, Mironov V, Liska R, Stampfl J, Ovsianikov A. Photopolymerization-based additive manufacturing for the development of 3D porous scaffolds. In: Biomaterials for Bone Regeneration, Dubruel and Vlierberghe: Woodhead Publishing, 2014.
129. Ovsianikov A, Muhleder S, Torgersen J, Li Z, Qin XH, Van Vlierberghe S, et al. Laser photofabrication of cell-containing hydrogel constructs. Langmuir 2014;30:3787-94.