[1] Torgersen J, Ovsianikov A, Mironov V et al. Photo-sensitive hydrogels for three-dimensional laser microfabrication in the presence of whole organisms[J]. Journal of Biomedical Optics, 17, 105008(2012). http://europepmc.org/abstract/MED/23070525

[2] Ge L, Liu L W, Jiang L N et al. Properties of hydrogel and its applications in biomedicine[J]. Journal of Biomedical Engineering, 32, 1369-1373(2015).

[3] Li C W, Davis B, Shea J et al. Optimization of micropatternedpoly(lactic-co-glycolic acid) films for enhancing dorsal root ganglion cell orientation and extension[J]. Neural Regeneration Research, 13, 105-111(2018).

[4] Boudriot U, Dersch R, Greiner A et al. Electrospinning approaches toward scaffold engineering: a brief overview[J]. Artificial Organs, 30, 785-792(2006).

[5] Timnak A, Gharebaghi F Y, Shariati R P et al. Fabrication of nano-structured electrospun collagen scaffold intended for nerve tissue engineering[J]. Journal of Materials Science: Materials in Medicine, 22, 1555-1567(2011). http://link.springer.com/article/10.1007/s10856-011-4316-5

[6] Kim C H, Khil M S, Kim H Y et al. An improved hydrophilicity via electrospinning for enhanced cell attachment and proliferation[J]. Journal of Biomedical Materials Research Part B: Applied Biomaterials, 78B, 283-290(2006).

[7] Cheng C M. LeDuc P R. Micropatterning polyvinyl alcohol as a biomimetic material through soft lithography with cell culture[J]. Molecular BioSystems, 2, 299-303(2006).

[8] Attalla R, Ling C, Selvaganapathy P. Fabrication and characterization of gels with integrated channels using 3D printing with microfluidic nozzle for tissue engineering applications[J]. Biomedical Microdevices, 18, 17(2016).

[9] Yang X C, Lu Z H, Wu H Y et al. Collagen-alginate asbioink for three-dimensional (3D) cell printing based cartilage tissue engineering[J]. Materials Science and Engineering: C, 83, 195-201(2018).

[10] Kengla C, Lee S J, Yoo J J et al. 3-D bioprinting technologies for tissue engineering applications[J]. Rapid Prototyping of Biomaterials, 269-288(2020). http://www.sciencedirect.com/science/article/pii/B9780081026632000113

[11] Yeong W Y, Chua C K, Leong K F et al. Indirect fabrication of collagen scaffold based on inkjet printing technique[J]. Rapid Prototyping Journal, 12, 229-237(2006).

[12] Ge Z X, Yu H B, Yang W G et al. Development of multi-dimensional cellco-culture via a novel microfluidic chip fabricated by DMD-based optical projection lithography[J]. IEEE Transactions on NanoBioScience, 18, 679-686(2019).

[13] Kunwar P. Jannini A V S, Xiong Z, et al. High-resolution 3D printing of stretchable hydrogel structures using optical projection lithography[J]. ACS Applied Materials & Interfaces, 12, 1640-1649(2020).

[14] Ouyang X, Zhang K, Wu J et al. Optical μ-printing of cellular-scale microscaffold arrays for 3D cell culture[J]. Scientific Reports, 7, 8880(2017).

[15] Sadeghi A, Pezeshki-Modaress M, Zandi M. Electrospun polyvinyl alcohol/gelatin/chondroitin sulfate nanofibrous scaffold: fabrication and in vitro evaluation[J]. International Journal of Biological Macromolecules, 114, 1248-1256(2018).

[16] Schlie S, Ngezahayo A, Ovsianikov A et al. Three-dimensional cell growth on structures fabricated from ORMOCER by two-photon polymerization technique[J]. Journal of Biomaterials Applications, 22, 275-287(2007).

[17] Sun R, Wang C Y, Hu Y L et al. Femtosecond laser processing hydrogel two-sided god microcolumn and its application[J]. Chinese Journal of Lasers, 46, 0902001(2019).

[18] Raimondi M T, Eaton S M, Laganà M et al. Three-dimensional structural niches engineered via two-photon laser polymerization promote stem cell homing[J]. Acta Biomaterialia, 9, 4579-4584(2013).

[19] Torgersen J, Qin X H, Li Z Q et al. Hydrogels for two-photon polymerization: a toolbox for mimicking the extracellular matrix[J]. Advanced Functional Materials, 23, 4542-4554(2013).

[20] Ovsianikov A, Mironov V, Stampfl J et al. Engineering 3D cell-culture matrices: multiphoton processing technologies for biological and tissue engineering applications[J]. Expert Review of Medical Devices, 9, 613-633(2012).

[21] Jeon H, Hidai H, Hwang D J et al. Fabrication of arbitrary polymer patterns for cell study by two-photon polymerization process[J]. Journal of Biomedical Materials Research Part A, 93A, 56-66(2010).

[22] Engelhardt S, Hoch E, Borchers K et al. Fabrication of 2D protein microstructures and 3D polymer-protein hybrid microstructures by two-photon polymerization[J]. Biofabrication, 3, 025003(2011). http://www.ncbi.nlm.nih.gov/pubmed/21562366

[23] Klein F, Richter B, Striebel T et al. Two-component polymer scaffolds for controlled three-dimensional cell culture[J]. Advanced Materials, 23, 1341-1345(2011).

[24] Nava M M, Raimondi M T, Credi C et al. Interactions between structural and chemical biomimetism in synthetic stem cell niches[J]. Biomedical Materials, 10, 015012(2015).

[25] Nava M M, di Maggio N, Zandrini T et al. Synthetic niche substrates engineered via two-photon laser polymerization for the expansion of human mesenchymal stromal cells[J]. Journal of Tissue Engineering and Regenerative Medicine, 11, 2836-2845(2017).

[26] Kawata S, Sun H B, Tanaka T et al. Finer features for functional microdevices[J]. Nature, 412, 697-698(2001). http://europepmc.org/abstract/MED/11507627

[27] Zhang J R, Guan Y C. Surface functional microstructure of biomedical materials prepared by ultrafast laser: a review[J]. Chinese Optics, 12, 199-213(2019).

[28] Di J K, Zhou M, Yang H F et al. Manufacturing micro-biological device and scaffold research with two-photon femtosecond laser technology[J]. Chinese Journal of Lasers, 36, 249-254(2009).

[29] Ehrlich J E, Wu X L, Lee I Y et al. Two-photon absorption and broadband optical limiting with bis-donor stilbenes[J]. Optics Letters, 22, 1843-1845(1997).

[30] Albota M, Beljonne D, Brédas J L et al. Design of organic molecules with large two-photon absorption cross sections[J]. Science, 281, 1653-1656(1998).

[31] Kuebler S M, Rumi M, Watanabe T et al. Optimizing two-photon initiators and exposure conditions for three-dimensional lithographic microfabrication[J]. Journal of Photopolymer Science and Technology, 14, 657-668(2001).

[32] Cumpston B H, Ananthavel S P, Barlow S et al. Two-photon polymerization initiators for three-dimensional optical data storage and microfabrication[J]. Nature, 398, 51-54(1999).

[33] Belfield K D, Schafer K J, Mourad W et al. Synthesis of new two-photon absorbing fluorene derivatives via Cu-mediated Ullmann condensations[J]. The Journal of Organic Chemistry, 65, 4475-4481(2000).

[34] Yang C, Zheng M, Li Y P et al. Poly(1, 4-diketo-3, 6-diphenylpyrrolo[3, 4-c]pyrrole-alt-3, 6-carbazole/2, 7-fluorene) as high-performance two-photon dyes[J]. Journal of Polymer Science Part A: Polymer Chemistry, 52, 944-951(2014).

[35] Jia X Q, Han W X, Xue T L et al. Diphenyl sulfone-based A-π-D-π-A dyes as efficient initiators for one-photon and two-photon initiated polymerization[J]. Polymer Chemistry, 10, 2152-2161(2019).

[36] Liska R, Seidl B. 1, 5-Diphenyl-1, 4-diyn-3-one: a highly efficient photoinitiator[J]. Journal of Polymer Science Part A: Polymer Chemistry, 43, 101-111(2005).

[37] Pucher N, Rosspeintner A, Satzinger V et al. Structure-activity relationship in D-π-A-π-D-based photoinitiators for the two-photon-induced photopolymerization process[J]. Macromolecules, 42, 6519-6528(2009).

[38] Tromayer M, Gruber P, Rosspeintner A et al. Wavelength-optimized two-photon polymerization using initiators based on multipolar aminostyryl-1, 3, 5-triazines[J]. Scientific Reports, 8, 17273(2018).

[39] Xing J F, Chen W Q, Dong X Z et al. Synthesis, optical and initiating properties of new two-photon polymerization initiators: 2, 7-Bis(styryl)anthraquinone derivatives[J]. Journal of Photochemistry and Photobiology A: Chemistry, 189, 398-404(2007).

[40] Xing J F, Chen W Q, Gu J et al. Designof high efficiency for two-photon polymerization initiator: combination of radical stabilization and large two-photon cross-section achieved by N-benzyl 3, 6-bis(phenylethynyl)carbazole derivatives[J]. Journal of Materials Chemistry, 17, 1433-1438(2007).

[41] Lu W E, Dong X Z, Chen W Q et al. Novel photoinitiator with a radical quenching moiety for confining radical diffusion in two-photon induced photo polymerization[J]. Journal of Materials Chemistry, 21, 5650-5659(2011). http://pubs.rsc.org/en/content/articlehtml/2011/jm/c0jm04025h

[42] Liu Z J, Chen T, Liu B et al. Two-photon absorption of a series of V-shape molecules: the influence of acceptor's strength on two-photon absorption in a noncentrosymmetric D-π-A-π-D system[J]. Journal of Materials Chemistry, 17, 4685-4690(2007).

[43] Woo H Y, Liu B, Kohler B et al. Solvent effects on the two-photon absorption of distyryl benzene chromophores[J]. Journal of the American Chemical Society, 127, 14721-14729(2005).

[44] Wan X J, Zhao Y X, Xue J Q et al. Water-soluble benzylidene cyclopentanone dye for two-photon photopolymerization[J]. Journal of Photochemistry and Photobiology A: Chemistry, 202, 74-79(2009).

[45] Li Z Q, Torgersen J, Ajami A et al. Initiation efficiency and cytotoxicity of novel water-soluble two-photon photoinitiators for direct 3D microfabrication of hydrogels[J]. RSC Advances, 3, 15939-15946(2013).

[46] Li S J, Li L D, Wu F P et al. A water-soluble two-photon photopolymerization initiation system: methylated-β-cyclodextrin complex of xanthene dye/aryliodonium salt[J]. Journal of Photochemistry and Photobiology A: Chemistry, 203, 211-215(2009). http://www.sciencedirect.com/science/article/pii/S1010603009000732

[47] Xing J F, Liu JH, Zhang T B et al. A water soluble initiator prepared through host-guest chemical interaction for microfabrication of 3D hydrogels via two-photon polymerization[J]. Journal of Materials Chemistry B, 2, 4318-4323(2014).

[48] Xing J F, Liu L, Song X Y et al. 3D hydrogels with high resolution fabricated by two-photon polymerization with sensitive water soluble initiators[J]. Journal of Materials Chemistry B, 3, 8486-8491(2015).

[49] Zheng Y C, Zhao Y Y, Zheng M L et al. Cucurbit[7]uril-carbazole two-photon photoinitiators for the fabrication of biocompatible three-dimensional hydrogel scaffolds by laser direct writing in aqueous solutions[J]. ACS Applied Materials & Interfaces, 11, 1782-1789(2019).

[50] Koroleva A, Gittard S, Schlie S et al. Fabrication of fibrin scaffolds with controlled microscale architecture by a two-photon polymerization-micromolding technique[J]. Biofabrication, 4, 015001(2012).

[51] Lee S H, Moon J J, West J L. Three-dimensional micropatterning of bioactive hydrogels via two-photon laser scanning photolithography for guided 3D cell migration[J]. Biomaterials, 29, 2962-2968(2008).

[52] Barry III R A, Shepherd R F, Hanson J N et al. Direct-write assembly of 3D hydrogel scaffolds for guided cell growth[J]. Advanced Materials, 21, 2407-2410(2009).

[53] Xiong Z, Zheng C L, Jin F et al. Magnetic-field-driven ultra-small 3D hydrogel microstructures: preparation of gel photoresist and two-photon polymerization microfabrication[J]. Sensors and Actuators B: Chemical, 274, 541-550(2018). http://www.sciencedirect.com/science/article/pii/S0925400518314321

[54] Raimondi M T, Eaton S M, Nava M M et al. Two-photon laser polymerization: from fundamentals to biomedical application in tissue engineering and regenerative medicine[J]. Journal of Applied Biomaterials & Functional Materials, 10, 55-65(2012).

[55] Li J Y, Li X J, Luo T, delivering targeted cells[J].Science Robotics et al. 3(19): eaat8829(2018).

[56] Greiner A M, Richter B, Bastmeyer M. Micro-engineered 3D scaffolds for cell culture studies[J]. Macromolecular Bioscience, 12, 1301-1314(2012).

[57] Correa D S, Tayalia P, Cosendey G et al. Two-photon polymerization for fabricating structures containing the biopolymer chitosan[J]. Journal of Nanoscience and Nanotechnology, 9, 5845-5849(2009).

[58] Spivey E C, Ritschdorff E T, Connell J L et al. Multiphoton lithography of unconstrained three-dimensional protein microstructures[J]. Advanced Functional Materials, 23, 333-339(2013).

[59] Lü C, Sun X C, Xia H et al. Humidity-responsive actuation of programable hydrogel microstructures based on 3D printing[J]. Sensors and Actuators B: Chemical, 259, 736-744(2018).

[60] Gou X R, Zheng M L, Zhao Y Y et al. Mechanical property of PEG hydrogel and the 3D red blood cell microstructures fabricated by two-photon polymerization[J]. Applied Surface Science, 416, 273-280(2017).

[61] Wei S, Liu J, Zhao Y et al. Protein-based 3D microstructures with controllable morphology and pH-responsive properties[J]. ACS Applied Materials & Interfaces, 9, 42247-42257(2017).

[62] Tang J, Peng R, Ding J D. The regulation of stem cell differentiation by cell-cell contact on micropatterned material surfaces[J]. Biomaterials, 31, 2470-2476(2010). http://europepmc.org/abstract/med/20022630

[63] Dai J, Kong N, Lu Y et al. Bioinspired conical micropattern modulates cell behaviors[J]. ACS Applied Bio Materials, 1, 1416-1423(2018).

[64] Käp ylä E, Aydogan D B et al. Direct laser writing of synthetic poly(amino acid) hydrogels and poly(ethylene glycol) diacrylates by two-photon polymerization[J]. Materials Science and Engineering: C, 43, 280-289(2014).

[65] Noh M, Choi Y H, An Y H et al. Magnetic nanoparticle-embedded hydrogel sheet with a groove pattern for wound healing application[J]. ACS Biomaterials Science & Engineering, 5, 3909-3921(2019).

[66] et alA bioinspired 3D shape olibanum-collagen-gelatin scaffolds with tunable porous microstructure for efficient neural tissue regeneration[J]. Biotechnology Progress, 36, e2918(2020). http://www.researchgate.net/publication/335867680_A_bio-inspired_3D_shape_olibanum-collagen-gelatin_scaffolds_with_tunable_porous_microstructure_for_efficient_neural_tissue_regeneration

     Ghorbani F, Ghorbani F, Zamanian A, Zamanian A, Kermanian F, Kermanian F et al. A bioinspired 3D shape olibanum-collagen-gelatin scaffolds with tunable porous microstructure for efficient neural tissue regeneration[J]. Biotechnology Progress, 36, e2918(2020).

[67] Yang L J, Ou Y C. The micro patterning of glutaraldehyde (GA)-crosslinked gelatin and its application to cell-culture[J]. Lab on a Chip, 5, 979-984(2005).

[68] Bello A B, Kim D, Kim D et al. Engineering and functionalization of gelatin biomaterials: from cell culture to medical applications[J]. Tissue Engineering. Part B, Reviews, 26, 164-180(2020).

[69] Lewis P L, Green R M, Shah R N. 3D-printed gelatin scaffolds of differing pore geometry modulate hepatocyte function and gene expression[J]. Acta Biomater, 69, 63-70(2018).

[70] Ovsianikov A. Deiwick A, van Vlierberghe S, et al. Laser fabrication of three-dimensional CAD scaffolds from photosensitive gelatin for applications in tissue engineering[J]. Biomacromolecules, 12, 851-858(2011).

[71] Brigo L, Urciuolo A, Giulitti S et al. 3D high-resolution two-photon crosslinked hydrogel structures for biological studies[J]. Acta Biomaterialia, 55, 373-384(2017).

[72] Ovsianikov A, Gruene M, Pflaum M et al. Laser printing of cells into 3D scaffolds[J]. Biofabrication, 2, 014104(2010). http://www.ncbi.nlm.nih.gov/pubmed/20811119

[73] Ovsianikov A, Malinauskas M, Schlie S et al. Three-dimensional laser micro- and nano-structuring of acrylated poly(ethylene glycol) materials and evaluation of their cytoxicity for tissue engineering applications[J]. Acta Biomaterialia, 7, 967-974(2011).

[74] Accardo A, Blatché M C, Courson R et al. Two-photon lithography and microscopy of 3D hydrogel scaffolds for neuronal cell growth[J]. Biomedical Physics & Engineering Express, 4, 027009(2018).

[75] Toole B P, Wight T N, Tammi M I. Hyaluronan-cell interactions in cancer and vascular disease[J]. The Journal of Biological Chemistry, 277, 4593-4596(2002).

[76] Kufelt O, El-Tamer A, Sehring C et al. Hyaluronic acid based materials for scaffolding via two-photon polymerization[J]. Biomacromolecules, 15, 650-659(2014).

[77] Kufelt O, El-Tamer A, Sehring C et al. Water-soluble photopolymerizable chitosan hydrogels for biofabrication via two-photon polymerization[J]. Acta Biomaterialia, 18, 186-195(2015).

[78] Gao W, Zheng M L, Jin F et al. Fast fabrication of large-area two-dimensional micro/nanostructure by femtosecond laser[J]. Laser & Optoelectronics Progress, 57, 111421(2020).