New frontiers in bioengineering: A perspective on the open challenges in bioprinting

Abstract

Bioprinting has emerged as a transformative technology in biofabrication, enabling the precise spatial arrangement of biomaterials, living cells, and bioactive factors to generate functional three-dimensional biological constructs. Recent advances are redefining the scope and impact of this field through innovations in both materials and methodologies. Multi-material and multiscale printing strategies are enhancing the ability to replicate the hierarchical architecture and functional gradients of native tissues, while the valorization of waste-derived biomaterials for bioink formulation is introducing sustainable solutions without compromising performance. The integration of bioprinting with organ-on-a-chip systems is providing highly sophisticated in vitro models for disease research and drug discovery, and in situ bioprinting techniques are opening new possibilities for direct, patient-specific tissue repair. Parallel to these developments, four-dimensional bioprinting introduces the dimension of time, allowing printed constructs to change shape, properties, or function in response to environmental stimuli. The application of artificial intelligence in process monitoring and quality control is improving reproducibility, predictive accuracy, and manufacturing efficiency, thus paving the way for standardized production. Looking ahead, the emerging concept of five-dimensional bioprinting— integrating spatial, temporal, and functional control—suggests a paradigm shift in the design and manufacturing of living systems. Collectively, these advances are broadening the technological capabilities of biofabrication and accelerating the translation of bioprinting from experimental settings toward transformative clinical and industrial applications. This review synthesizes current progress while outlining the opportunities and challenges that will shape the next generation of bioprinting technologies.

Keywords

Multi-material and multiscale bioprinting / Waste biomaterials / Artificial intelligence-enhanced quality control / In situ bioprinting / Organ-on-a-chip / Four dimensional and five-dimensional bioprinting

Funding

This work is supported by the European Union’s Horizon Europe research and innovation program (grant no. 101191747, TENTACLE; grant no. 101191804, LUMINATE; grant no. 101178568, DAEDALUS) and from the European Union–Next Generation EU, Mission 4-Component 1 (CUP I53D23002200006), through the Prin2022 Prometheus project, “4D printing self-deploying bioenabled polymer scaffolds for the non-invasive treatment of bleeding intestinal ulcers” (grant no.: 2022BZLTTK). Additional funding was provided by the European Union–Next Generation EU, Mission 4-Component 2, Investment 1.5 (CUP I53C22000780001) under the Tuscany Health Ecosystem, Spoke 4: Nanotechnologies for diagnosis and therapy. This work was also partially supported by the Italian Ministry of Education and Research (MUR; In the Departments of Excellence program) within the framework of the FoReLab and CrossLab projects (Departments of Excellence).

Conflict of Interest

Carmelo De Maria, Giovanni Vozzi, and Gabriele Maria Fortunato serve as the Editorial Board Member of the journal, but did not in any way involve in the editorial and peer-review process conducted for this paper, directly or indirectly. Other authors declare they have no competing interests.

References

[1] ISO/ASTM 52900:2015(en), Additive manufacturing—General principles—Terminology. https://www.iso.org/obp/ui/#iso:std:iso-astm:52900:ed-1:v1:en

[2] Moroni L, Boland T, Burdick JA, et al. Biofabrication: A Guide to Technology and Terminology. Trends Biotechnol. 2018;36(4):384-402. doi: 10.1016/j.tibtech.2017.10.015

[3] Ng WL, Vyas C, Huang B, Yeong WY, Bartolo P. Advanced bioprinting strategies for fabrication of biomimetic tissues and organs. Int J Extrem Manuf Inst Phys. 2025;7(6). doi: 10.1088/2631-7990/adeee0

[4] Sachlos E, Czernuszka JT, Gogolewski S, Dalby M. Making tissue engineering scaffolds work. Review on the application ofsolid freeform fabrication technology to the production of tissue engineering scaffolds. Eur Cell Mater. 2003;5:29-40. doi: 10.22203/ecm.v005a03

[5] Bartolo PJS, Almeida H, Laoui T. Rapid prototyping and manufacturing for tissue engineering scaffolds. Int J Comput Appl Technol. 2009;36(1):1-9. doi: 10.1504/IJCAT.2009.026664

[6] Seol YJ, Kang HW, Lee SJ, Atala A, Yoo JJ. Bioprinting technology and its applications. Eur J Cardio-Thorac. Surg. 2014;46(3):342-348. doi: 10.1093/ejcts/ezu148

[7] Dutta RC, Dey M, Dutta AK, Basu B. Competent processing techniques for scaffolds in tissue engineering. Biotechnol Adv. 2017;35(2):240-250. doi: 10.1016/j.biotechadv.2017.01.001

[8] Ozbolat IT, Hospodiuk M. Current advances and future perspectives in extrusion-based bioprinting. Biomaterials. 2016;76:321-343. doi: 10.1016/j.biomaterials.2015.10.076

[9] Roy A, Saxena V, Pandey LM. 3D printing for cardiovascular tissue engineering: a review. Mater Technol. 2018;33(6):433-442. doi: 10.1080/10667857.2018.1456616

[10] Zhang YS, Haghiashtiani G, Hubscher T, et al. 3D extrusion bioprinting. Nat Revi Methods Primers. 2021;1(1):75. doi: 10.1038/s43586-021-00073-8

[11] Duan B. State-of-the-Art Review of 3D Bioprinting for Cardiovascular Tissue Engineering. Ann Biomed Eng. 2017;45(1):195-209. doi: 10.1007/s10439-016-1607-5

[12] Cui X, Boland T, D . D’Lima D, K. Lotz M. Thermal Inkjet Printing in Tissue Engineering and Regenerative Medicine. Recent Pat Drug Deliv Formul. 2012;6(2):149-155. doi: 10.2174/187221112800672949

[13] Fortunato GM, De Maria C, Eglin D, Serra T, Vozzi G. An ink-jet printed electrical stimulation platform for muscle tissue regeneration. Bioprinting. 2018;11. doi: 10.1016/j.bprint.2018.e00035

[14] Ng WL, Shkolnikov V. Jetting-based bioprinting: process, dispense physics, and applications. Biodes Manuf. 2024;7(5):771-799. doi: 10.1007/s42242-024-00285-3

[15] Li Y, Zhang X, Zhang X, Zhang Y, Hou D. Recent Progress of the Vat Photopolymerization Technique in Tissue Engineering: A Brief Review of Mechanisms, Methods, Materials, and Applications. Polymers. 2023;15(19). doi: 10.3390/polym15193940

[16] Borovjagin A V. , Ogle BM, Berry JL, Zhang J. From Microscale Devices to 3D Printing: Advances in Fabrication of 3D Cardiovascular Tissues. Circ Res. 2017;120(1):150-165. doi: 10.1161/CIRCRESAHA.116.308538

[17] Jang J. 3D bioprinting and in vitro cardiovascular tissue modeling. Bioengineering. 2017;4(3). doi: 10.3390/bioengineering4030071

[18] Bernal PN, Delrot P, Loterie D, et al. Volumetric Bioprinting of Complex Living‐Tissue Constructs within Seconds. Adv Mater. 2019;31(42). doi: 10.1002/adma.201904209

[19] Loterie D, Delrot P, Moser C. High-resolution tomographic volumetric additive manufacturing. Nat Commun.

[20] Bhardwaj N, Kundu SC. Electrospinning: A fascinating fiber fabrication technique. Biotechnol Adv. 2010;28(3):325-347. doi: 10.1016/j.biotechadv.2010.01.004

[21] Haider A, Haider S, Kang IK. A comprehensive review summarizing the effect of electrospinning parameters and potential applications of nanofibers in biomedical and biotechnology. Arab J Chem. 2018;11(8):1165-1188. doi: 10.1016/j.arabjc.2015.11.015

[22] Daenicke J, Lammlein M, Steinhubl F, Schubert DW. Revealing key parameters to minimize the diameter of polypropylene fibers produced in the melt electrospinning process. e-Polymers. 2019;19(1):330-340. doi: 10.1515/epoly-2019-0034

[23] O’Neill KL, Dalton PD. A Decade of Melt Electrowriting. Small Methods. 2023;7(7). doi: 10.1002/smtd.202201589

[24] Gopinathan J, Noh I. Recent trends in bioinks for 3D printing. Biomater Res. 2018;22(1):11. doi: 10.1186/s40824-018-0122-1

[25] Panwar A, Tan LP. Current status of bioinks for micro extrusion-based 3D bioprinting. Molecules. 2016;21(6). doi: 10.3390/molecules21060685

[26] Cui H, Zhu W, Nowicki M, Zhou X, Khademhosseini A, Zhang LG. Hierarchical Fabrication of Engineered Vascularized Bone Biphasic Constructs via Dual 3D Bioprinting: Integrating Regional Bioactive Factors into Architectural Design. Adv Healthc Mater. 2016;5(17):2174-2181. doi: 10.1002/adhm.201600505

[27] Yuan Z, Bai X, Li S, et al. Multimaterial and Multidimensional Bioprinting in Regenerative Medicine: Advances, Limitations, and Future Directions. Adv Healthc Mater. 2025;14(18). doi: 10.1002/adhm.202500475

[28] Criscenti G, De Maria C, Vozzi G, Moroni L. Characterization of Additive Manufactured Scaffolds. In: 3D Printing and Biofabrication. Springer International Publishing; 2017:1-25. doi: 10.1007/978-3-319-40498-1_4-1

[29] Micalizzi S, Russo L, Giacomelli C, et al. Multimaterial and multiscale scaffold for engineering enthesis organ. Int J Bioprint. 2023;9(5). doi: 10.18063/ijb.763

[30] Visser J, Peters B, Burger TJ, et al. Biofabrication of multi-material anatomically shaped tissue constructs.

[31] Chiesa I, Fortunato GM, Lapomarda A, et al. Ultrasonic mixing chamber as an effective tool for the biofabrication of fully graded scaffolds for interface tissue engineering. Int J Artif Organs. 2019;42(10):586-594. doi: 10.1177/0391398819852960

[32] Ainsworth MJ, Chirico N, de Ruijter M, et al. Convergence of melt electrowriting and extrusion-based bioprinting for vascular patterning of a myocardial construct. Biofabrication. 2023;15(3):035025. doi: 10.1088/1758-5090/ace07f

[33] Grosbacher G, Bartolf‐Kopp M, Gergely C, et al. Volumetric Printing Across Melt Electrowritten Scaffolds Fabricates Multi‐Material Living Constructs with Tunable Architecture and Mechanics. Adv Mater. 2023;35(32). doi: 10.1002/adma.202300756

[34] Kang D, Hong G, An S, et al. Bioprinting of Multi scaled Hepatic Lobules within a Highly Vascularized Construct. Small. 2020;16(13). doi: 10.1002/smll.201905505

[35] Puistola P, Miettinen S, Skottman H, Moro A. Novel strategy for multi-material 3D bioprinting of human stem cell based corneal stroma with heterogenous design. Mater Today Bio. 2024;24:100924. doi: 10.1016/j.mtbio.2023.100924

[36] Wan W, Wang X, Zhang R, et al. Construction of artificial lung tissue structure with 3D-inkjet bioprinting core for pulmonary disease evaluation. J Tissue Eng. 2025;16. doi: 10.1177/20417314251328128

[37] Miri AK, Mostafavi E, Khorsandi D, Hu SK, Malpica M, Khademhosseini A. Bioprinters for organs-on-chips. Biofabrication. 2019;11(4):042002. doi: 10.1088/1758-5090/ab2798

[38] Chand R, Kamei K ichiro, Vijayavenkataraman S. Advances in Microfluidic Bioprinting for Multi-Material Multi-Cellular Tissue Constructs. Cell Ther Eng Connect. 2025;1(1):1. doi: 10.69709/CellEngC.2024.111335

[39] Bonatti AF, Batoni E, Fortunato GM, Vitale-Brovarone C, Vozzi G, De Maria C. Robust design methodologies to engineer multimaterial and multiscale bioprinters. Bioprinting. 2024;44. doi: 10.1016/j.bprint.2024.e00372

[40] Guerra A, Fortunato GM, Batoni E, Vozzi G, De Maria C. Multi-material and multi-scale platform for robotic based in situ bioprinting. Results Eng. 2025;25. doi: 10.1016/j.rineng.2025.104219

[41] Prendergast ME, Solorzano RD, Cabrera D. Bioinks for biofabrication: current state and future perspectives. J 3D Print Med. 2017;1(1):49-62. doi: 10.2217/3dp-2016-0002

[42] Chimene D, Lennox KK, Kaunas RR, Gaharwar AK. Advanced Bioinks for 3D Printing: A Materials Science Perspective. Ann Biomed Eng. 2016;44(6):2090-2102. doi: 10.1007/s10439-016-1638-y

[43] Benwood C, Chrenek J, Kirsch RL, et al. Natural biomaterials and their use as bioinks for printing tissues. Bioengineering. 2021;8(2):1-19. doi: 10.3390/bioengineering8020027

[44] Groll J, Burdick JA, Cho DW, et al. A definition of bioinks and their distinction from biomaterial inks. Biofabrication. 2019;11(1):013001. doi: 10.1088/1758-5090/aaec52

[45] Chen XB, Fazel Anvari-Yazdi A, Duan X, et al. Biomaterials/bioinks and extrusion bioprinting. Bioact Mater. 2023;28:511-536. doi: 10.1016/j.bioactmat.2023.06.006

[46] Rangel R, Swanson WB, Wu DT. The future of cell-instructive biomaterials for tissue regeneration–a perspective from early career clinician-scientists. Front Mater. 2024;10. doi: 10.3389/fmats.2023.1328904

[47] Elango J, Zamora-Ledezma C. Rheological, Structural, and Biological Trade-Offs in Bioink Design for 3D Bioprinting. Gels. 2025;11(8):659. doi: 10.3390/gels11080659

[48] Zieliński PS, Gudeti PKR, Rikmanspoel T, Włodarczyk-Biegun MK. 3D printing of bio-instructive materials: Toward directing the cell. Bioact Mater. 2023;19:292-327. doi: 10.1016/j.bioactmat.2022.04.008

[49] Brovold M, Almeida JI, Pla-Palacin I, et al. Naturally-Derived Biomaterials for Tissue Engineering Applications. Adv Exp Med Biol. 2018;1077:421-449. doi: 10.1007/978-981-13-0947-2_23

[50] Whenish R, Ramakrishna S, Jaiswal AK, Manivasagam G. A framework for the sustainability implications of 3D bioprinting through nature-inspired materials and structures. Biodes Manuf. 2022;5(2):412-423. doi: 10.1007/s42242-021-00168-x

[51] Pulidori E, Micalizzi S, Bramanti E, et al. One-pot process: Microwave-assisted keratin extraction and direct electrospinning to obtain keratin-based bioplastic. Int J Mol Sci. 2021;22(17). doi: 10.3390/ijms22179597

[52] Trakoolwannachai V, Kheolamai P, Ummartyotin S. Characterization of hydroxyapatite from eggshell waste and polycaprolactone (PCL) composite for scaffold material. Compos B Eng. 2019;173:106974. doi: 10.1016/j.compositesb.2019.106974

[53] Lapomarda A, De Acutis A, Chiesa I, et al. Pectin-GPTMS Based Biomaterial: Toward a Sustainable Bioprinting of 3D scaffolds for Tissue Engineering Application. Biomacromolecules. 2020;21(2):319-327. doi: 10.1021/acs.biomac.9b01332

[54] Piras CC, Fernandez-Prieto S, De Borggraeve WM. Nanocellulosic materials as bioinks for 3D bioprinting. Biomater Sci. 2017;5(10):1988-1992. doi: 10.1039/c7bm00510e

[55] Zamri MFMA, Bahru R, Amin R, et al. Waste to health: Areview of waste derived materials for tissue engineering. J Clean Prod. 2021;290. doi: 10.1016/j.jclepro.2021.125792

[56] Kumar Gupta G, De S, Franco A, Balu AM, Luque R. Sustainable Biomaterials: Current Trends, Challenges and Applications. Molecules. 2016;21(1):48. doi: 10.3390/molecules21010048

[57] Jovic TH, Kungwengwe G, Mills AC, Whitaker IS. Plant-Derived Biomaterials: A Review of 3D Bioprinting and Biomedical Applications. Front Mech Eng. 2019;5:1-18. doi: 10.3389/fmech.2019.00019

[58] Lapomarda A, Acutis A De, Maria C De, Vozzi G. Pectin-Based Scaffolds for Tissue Engineering Applications. In: Masuelli MA, editors. Pectins. IntechOpen; 2021. doi: 10.5772/intechopen.101521

[59] Bebiano LB, Presa R, Vieira F, Lourenco BN, Pereira RF. Bioinspired and Photo-Clickable Thiol-Ene Bioinks for the Extrusion Bioprinting of Mechanically Tunable 3D Skin Models. Biomimetics. 2024;9(4). doi: 10.3390/biomimetics9040228

[60] Wang JH, Tsai CW, Tsai NY, et al. An injectable, dual crosslinkable hybrid pectin methacrylate (PECMA)/gelatin methacryloyl (GelMA) hydrogel for skin hemostasis applications. Int J Biol Macromol. 2021;185:441-450. doi: 10.1016/j.ijbiomac.2021.06.162

[61] Lapomarda A, Pulidori E, Cerqueni G, et al. Pectin as Rheology Modifier of a Gelatin-Based Biomaterial Ink. Materials. 2021;14(11). doi: 10.3390/ma14113109

[62] Lapomarda A, Cerqueni G, Geven MA, et al. Physicochemical Characterization of Pectin-Gelatin Biomaterial Formulations for 3D Bioprinting. Macromol Biosci. 2021;21(9):1-11. doi: 10.1002/mabi.202100168

[63] Jusoh WNLW, Sajab MS, Abdul PM, Kaco H. Recent Advances in 3D Bioprinting: A Review of Cellulose-Based Biomaterials Ink. Polymers. 2022;14(11). doi: 10.3390/polym14112260

[64] Tabatabaei Hosseini BS, Meadows K, Gabriel V, Hu J, Kim K. Biofabrication of Cellulose-based Hydrogels for Advanced Wound Healing: A Special Emphasis on 3D Bioprinting. Macromol Biosci. 2024;24(5). doi: 10.1002/mabi.202300376

[65] Melilli G, Carmagnola I, Tonda-Turo C, et al. DLP 3D printing meets lignocellulosic biopolymers: Carboxymethyl cellulose inks for 3D biocompatible hydrogels. Polymers. 2020;12(8). doi: 10.3390/POLYM12081655

[66] Sawkins MJ, Mistry P, Brown BN, Shakesheff KM, Bonassar LJ, Yang J. Cell and protein compatible 3D bioprinting of mechanically strong constructs for bone repair. Biofabrication. 2015;7(3). doi: 10.1088/1758-5090/7/3/035004

[67] Henriksson I, Gatenholm P, Hagg DA. Increased lipid accumulation and adipogenic gene expression of adipocytes in 3D bioprinted nanocellulose scaffolds. Biofabrication. 2017;9(1). doi: 10.1088/1758-5090/aa5c1c

[68] Kong X, Chen L, Li B, Quan C, Wu J. Applications of oxidized alginate in regenerative medicine. J Mater Chem B. 2021;9(12):2785-2801. doi: 10.1039/D0TB02691C

[69] Hasany M, Talebian S, Sadat S, et al. Synthesis, properties, and biomedical applications of alginate methacrylate (ALMA)-based hydrogels: Current advances and challenges. Appl Mater Today. 2021;24. doi: 10.1016/j.apmt.2021.101150

[70] Pagnotta G, Becconi M, Malferrari M, et al. Development of a tissue construct with spatially controllable stiffness via a one-step 3D bioprinting and dual-crosslinking process. Mater Adv. 2023;4(16):3491-3505. doi: 10.1039/d3ma00319a

[71] Muller M, Ozturk E, Arlov O, Gatenholm P, Zenobi-Wong M. Alginate Sulfate–Nanocellulose Bioinks for Cartilage Bioprinting Applications. Ann Biomed Eng. 2017;45(1):210-223. doi: 10.1007/s10439-016-1704-5

[72] Markstedt K, Mantas A, Tournier I, Martinez Avila H, Hagg D, Gatenholm P. 3D bioprinting human chondrocytes with nanocellulose-alginate bioink for cartilage tissue engineering applications. Biomacromolecules. 2015;16(5):1489-1496. doi: 10.1021/acs.biomac.5b00188

[73] Maturavongsadit P, Narayanan LK, Chansoria P, Shirwaiker R, Benhabbour SR. Cell-Laden Nanocellulose/Chitosan- Based Bioinks for 3D Bioprinting and Enhanced Osteogenic Cell Differentiation. ACS Appl Bio Mater. 2021;4(3):2342-2353.doi: 10.1021/acsabm.0c01108

[74] Lazaridou M, Bikiaris DN, Lamprou DA. 3D Bioprinted Chitosan-Based Hydrogel Scaffolds in Tissue Engineering and Localised Drug Delivery. Pharmaceutics. 2022;14(9). doi: 10.3390/pharmaceutics14091978

[75] Klak M, Kosowska K, Czajka M, et al. The Impact of the Methacrylation Process on the Usefulness of Chitosan as a Biomaterial Component for 3D Printing. J Funct Biomater. 2024:15(9).251. doi: 10.3390/jfb15090251

[76] Coşkun S, Akbulut SO, Sarıkaya B, Cakmak S, Gumuşderelioğlu M. Formulation of chitosan and chitosannanoHAp bioinks and investigation of printability with optimized bioprinting parameters. Int J Biol Macromol. 2022;222:1453-1464. doi: 10.1016/j.ijbiomac.2022.09.078

[77] He Y, Derakhshanfar S, Zhong W, et al. Characterization and Application of Carboxymethyl Chitosan-Based Bioink in Cartilage Tissue Engineering. J Nanomater. 2020;2020. doi: 10.1155/2020/2057097

[78] Garcia-Garcia A, Perez-Alvarez L, Ruiz-Rubio L, Larrea-Sebal A, Martin C, Vilas-Vilela JL. Extrusion-Based 3D Printing of Photocrosslinkable Chitosan Inks. Gels. 2024;10(2). doi: 10.3390/gels10020126

[79] Yuce-Erarslan E, Tutar R, İzbudak B, et al. Photocrosslinkable chitosan and gelatin-based nanohybrid bioinks for extrusion-based 3D-bioprinting. Int J Polym Mater Polym Biomater. 2023;72(1):1-12. doi: 10.1080/00914037.2021.1981322

[80] Yamamura H, da Silva VHP, Ruiz PLM, et al. Physicochemical characterization and biocompatibility of hydroxyapatite derived from fish waste. J Mech Behav Biomed Mater. 2018;80:137-142. doi: 10.1016/j.jmbbm.2018.01.035

[81] Ingole VH, Vuherer T, Maver U, Kokol V, Vinchurkar A, Ghule A V. Mechanical properties and cytotoxicity of differently structured nanocellulose-hydroxyapatite based composites for bone regeneration application. Nanomaterials. 2020;10(1). doi: 10.3390/nano10010025

[82] Wu CS, Wang SS, Wu DY, Shih WL. Novel composite 3D-printed filament made from fish scale-derived hydroxyapatite, eggshell and polylactic acid via a fused fabrication approach. Addit Manuf. 2021;46:102169. doi: 10.1016/j.addma.2021.102169

[83] Wenz A, Janke K, Hoch E, Tovar GEM, Borchers K, Kluger PJ. Hydroxyapatite-modified gelatin bioinks for bone bioprinting. BioNanoMaterials. 2016;17(3-4). doi: 10.1515/bnm-2015-0018

[84] Alkaron W, Almansoori A, Balazsi K, Balazsi C. Hydroxyapatite-Based Natural Biopolymer Composite for Tissue Regeneration. Materials. 2024;17(16). doi: 10.3390/ma17164117

[85] Han Y, Wei Q, Chang P, et al. Three-dimensional printing of hydroxyapatite composites for biomedical application. Crystals. 2021;11(4). doi: 10.3390/cryst11040353

[86] Maji K, Dasgupta S, Bhaskar R, Gupta MK. Photocrosslinked alginate nano-hydroxyapatite paste for bone tissue engineering. Biomed Mater. 2020;15(5):055019. doi: 10.1088/1748-605X/ab9551

[87] Chen Q, Zou B, Wang X, et al. SLA-3d printed building and characteristics of GelMA/HAP biomaterials with gradient porous structure. J Mech Behav Biomed Mater. 2024;155:106553. doi: 10.1016/j.jmbbm.2024.106553

[88] Alexa RL, Cucuruz A, Ghițulică CD, et al. 3D Printable Composite Biomaterials Based on GelMA and Hydroxyapatite Powders Doped with Cerium Ions for Bone Tissue Regeneration. Int J Mol Sci. 2022;23(3). doi: 10.3390/ijms23031841

[89] Fortunato GM, Da Ros F, Bisconti S, et al. Electrospun structures made of a hydrolyzed keratin-based biomaterial for development of in vitro tissue models. Front Bioeng Biotechnol. 2019;7:1-12. doi: 10.3389/fbioe.2019.00174

[90] Vasconcelos A, Freddi G, Cavaco-Paulo A. Biodegradable Materials Based on Silk Fibroin and Keratin. Biomacromolecules. 2008;9(4):1299-1305. doi: 10.1021/bm7012789

[91] Krishani M, Chong JN, Lim WR, Jusoh N, Sambudi NS, Suhaimi H. Synthesis and Characterization of Keratin-Based Scaffold for Potential Tissue Engineering Applications. Fibers. 2025;13(7):97. doi: 10.3390/fib13070097

[92] Navarro J, Clohessy RM, Holder RC, et al. In Vivo Evaluation of Three-Dimensional Printed, Keratin-Based Hydrogels in a Porcine Thermal Burn Model. Tissue Eng Part A. 2020;26(5-6):265-278. doi: 10.1089/ten.tea.2019.0181

[93] Akdag Z, Izgordu MS, Ayran M, et al. Methacrylated keratin biopolymer with tunable properties for advanced biomedical applications. Mater Lett. 2026;405:139713. doi: 10.1016/j.matlet.2025.139713

[94] Bedir T, Baykara D, Yildirim R, et al. Three-Dimensional-Printed GelMA-KerMA Composite Patches as an Innovative Platform for Potential Tissue Engineering of Tympanic Membrane Perforations. Nanomaterials. 2024;14(7):563. doi: 10.3390/nano14070563

[95] Arif ZU, Khalid MY, Noroozi R, et al. Additive manufacturing of sustainable biomaterials for biomedical applications. Asian J Pharm Sci. 2023;18(3):100812. doi: 10.1016/j.ajps.2023.100812

[96] Loukelis K, Helal ZA, Mikos AG, Chatzinikolaidou M. Nanocomposite Bioprinting for Tissue Engineering Applications. Gels. 2023;9(2):103. doi: 10.3390/gels9020103

[97] Vyas J, Raytthatha N, Vyas P, et al. Biomaterial-Based Additive Manufactured Composite/Scaffolds for Tissue Engineering and Regenerative Medicine: A Comprehensive Review. Polymers. 2025;17(8):1090. doi: 10.3390/polym17081090

[98] Yates M, Ramos-Gomez M, Civantos A, et al. Beverage waste derived biomaterials for tissue engineering. Green Chem. 2017;19(19):4520-4526. doi: 10.1039/C7GC01951C

[99] Harrison C, Gokoglan E, Day RM. Bacterial cellulose scaffolds derived from brewing waste for cultivated meat applications. Front Nutr. 2025;12. doi: 10.3389/fnut.2025.1656960

[100] Gu Y, Forget A, Shastri VP. Biobridge: An Outlook on Translational Bioinks for 3D Bioprinting. Adv Sci. 2022;9(3):2103469. doi: 10.1002/advs.202103469

[101] Ullah MW, Ul‐Islam M, Shehzad A, et al. From Bioinks to Functional Tissues and Organs: Advances, Challenges, and the Promise of 3D Bioprinting. Macromol Mater Eng. 2025;310(12). doi: 10.1002/mame.202500251

[102] Ma D, Liu J, Lu WW, Liu W, Ruan C. Dynamic bioinks for tissue/organ bioprinting: Principle, challenge, and perspective. Prog Mater Sci. 2026;155:101527. doi: 10.1016/j.pmatsci.2025.101527

[103] Parak A, Pradeep P, du Toit LC, Kumar P, Choonara YE, Pillay V. Functionalizing bioinks for 3D bioprinting applications. Drug Discov Today. 2019;24(1):198-205. doi: 10.1016/j.drudis.2018.09.012

[104] Vijayavenkataraman S. 3D Bioprinting: Challenges in Commercialization and Clinical Translation. J 3D Print Med. 2023;7(2). doi: 10.2217/3dp-2022-0026

[105] Mirzaei M, Okoro OV, Nie L, Petri DFS, Shavandi A. Protein-Based 3D Biofabrication of Biomaterials. Bioengineering. 2021;8(4):48. doi: 10.3390/bioengineering8040048

[106] Advanced Biomatrix PhotoAlginate.2026 Available from: https://advancedbiomatrix.com/photoalginate.html [Last accessed on 2026 Jan 13].

[107] Chitosan Bioink.2026. Available from: https://www.adbioink.com/product/chitosan-bioink/ [Last accessed on 2026 Jan 13].

[108] Cellink Bioink.2026. Available from: https://www.cellink.com/product/cellink-bioink/?country=IT [Last accessed on 2026 Jan 13].

[109] Perin F, Ouyang L, Lim KS, et al. Bioprinted Constructs in the Regulatory Landscape: Current State and Future Perspectives. Adv Mater. 2025;38(4). doi: 10.1002/adma.202504037

[110] Chiticaru EA, Ioniță M. Commercially available bioinks and state-of-the-art lab-made formulations for bone tissue engineering: A comprehensive review. Mater Today Bio. 2024;29:101341. doi: 10.1016/j.mtbio.2024.101341

[111] Ghosh S, Yi HG. A Review on Bioinks and their Application in Plant Bioprinting. Int J Bioprint. 2022;8(4):612. doi: 10.18063/ijb.v8i4.612

[112] Bonatti AF, Fortunato GM, De Maria C, Vozzi G. Bioprinting technologies: an overview. In: Bioprinting. Elsevier; 2022:19-49. doi:10.1016/b978-0-323-85430-6.00006-6

[113] Santoni S, Gugliandolo SG, Sponchioni M, Moscatelli D, Colosimo BM. 3D bioprinting: current status and trends—a guide to the literature and industrial practice. Biodes Manuf. 2022;5(1):14-42. doi: 10.1007/s42242-021-00165-0

[114] Li P, Faulkner A. 3D Bioprinting Regulations: A UK/EU Perspective. Eur J Risk Regul. 2017;8(2):441-447. doi: 10.1017/err.2017.19

[115] Li P, Faulkner A, Medcalf N. 3D bioprinting in a 2D regulatory landscape: gaps, uncertainties, and problems. Law Innov Technol. 2020;12(1):1-29. doi: 10.1080/17579961.2020.1727054

[116] Di Pietro L, Ravizza A, Vozzi G, Diaz Lantada A, Ahluwalia A, De Maria C. European regulatory framework for the clinical translation of bioprinted scaffolds and tissues. Biomed Sci Eng. 2019;3(3):11-12. doi: 10.4081/bse.2019.108

[117] Hourd P, Medcalf N, Segal J, Williams DJ. A 3D bioprinting exemplar of the consequences of the regulatory requirements on customized processes. Regen Med. 2015;10(7):863-883. doi: 10.2217/rme.15.52

[118] Bonatti AF, Chiesa I, Vozzi G, De Maria C. Open-source CAD-CAM simulator of the extrusion-based bioprinting process. Bioprinting. 2021;24:e00172. doi: 10.1016/j.bprint.2021.e00172

[119] Paxton N, Smolan W, Bock T, Melchels F, Groll J, Jungst T. Proposal to assess printability of bioinks for extrusion based bioprinting and evaluation of rheological properties governing bioprintability. Biofabrication. 2017;9(4):044107. doi: 10.1088/1758-5090/aa8dd8

[120] Ribeiro A, Blokzijl MM, Levato R, et al. Assessing bioink shape fidelity to aid material development in 3D bioprinting. Biofabrication. 2018;10(1):014102. doi: 10.1088/1758-5090/aa90e2

[121] Armstrong AA, Pfeil A, Alleyne AG, Wagoner Johnson AJ. Process monitoring and control strategies in extrusion based bioprinting to fabricate spatially graded structures. Bioprinting. 2021;21:e00126. doi: 10.1016/j.bprint.2020.e00126

[122] Zanderigo G, Bracco F, Semeraro Q, Colosimo BM. In-situ Printability Maps (IPM): A new approach for in-situ printability assessment with application to extrusion-based bioprinting. Bioprinting. 2023;36:e00320. doi: 10.1016/j.bprint.2023.e00320

[123] Chiesa I, Ligorio C, Bonatti AF, et al. Modeling the Three-Dimensional Bioprinting Process of β-Sheet Self-Assembling Peptide Hydrogel Scaffolds. Front Med Technol. 2020;2:1-16. doi: 10.3389/fmedt.2020.571626

[124] Comminal R, Serdeczny MP, Pedersen DB, Spangenberg J. Motion planning and numerical simulation of material deposition at corners in extrusion additive manufacturing. Addit Manuf. 2019;29:100753. doi: 10.1016/j.addma.2019.06.005

[125] Armstrong AA, Alleyne AG, Wagoner Johnson AJ. 1D and 2D error assessment and correction for extrusion-based bioprinting using process sensing and control strategies. Biofabrication. 2020;12(4). doi: 10.1088/1758-5090/aba8ee

[126] Petsiuk AL, Pearce JM. Open source computer vision based layer-wise 3D printing analysis. Addit Manuf. 2020;36:101473. doi: 10.1016/j.addma.2020.101473

[127] Armstrong AA, Norato J, Alleyne AG, Wagoner Johnson AJ. Direct process feedback in extrusion-based 3D bioprinting. Biofabrication. 2020;12(1):015017. doi: 10.1088/1758-5090/ab4d97

[128] Straus S, Meutelet R, Radosevic L, Gretzinger S, Hubbuch J. Image analysis as PAT-Tool for use in extrusion-based bioprinting. Bioprinting. 2021;21:e00112. doi: 10.1016/j.bprint.2020.e00112

[129] Straus S, Schroth B, Hubbuch J. Evaluation of the Reproducibility and Robustness of Extrusion-Based Bioprinting Processes Applying a Flow Sensor. Front Bioeng Biotechnol. 2022;10:1-14. doi: 10.3389/fbioe.2022.831350

[130] Wenger L, Straus S, Hubbuch J. Automated and dynamic extrusion pressure adjustment based on real-time flow rate measurements for precise ink dispensing in 3D bioprinting. Bioprinting. 2022;28:e00229. doi: 10.1016/j.bprint.2022.e00229

[131] Narayanan LK, Thompson TL, Shirwaiker RA, Starly B. Label free process monitoring of 3D bioprinted engineered constructs via dielectric impedance spectroscopy. Biofabrication. 2018;10(3):035012. doi: 10.1088/1758-5090/aaccbf

[132] Guo T, Holzberg TR, Lim CG, et al. 3D printing PLGA: A quantitative examination of the effects of polymer composition and printing parameters on print resolution. Biofabrication. 2017;9(2):024101. doi: 10.1088/1758-5090/aa6370

[133] Kengla C, Renteria E, Wivell C, Atala A, Yoo JJ, Lee SJ. Clinically Relevant Bioprinting Workflow and Imaging Process for Tissue Construct Design and Validation. 3D Print Addit Manuf. 2017;4(4):239-247. doi: 10.1089/3dp.2017.0075

[134] Schmieg B, Gretzinger S, Schuhmann S, Guthausen G, Hubbuch J. Magnetic resonance imaging as a tool for quality control in extrusion-based bioprinting. Biotechnol J. 2022;17(5). doi: 10.1002/biot.202100336

[135] Fujimoto JG, Pitris C, Boppart SA, Brezinski ME. Optical coherence tomography: An emerging technology for biomedical imaging and optical biopsy. Neoplasia. 2000;2(1-2):9-25. doi: 10.1038/sj.neo.7900071

[136] Yang S, Wang L, Chen Q, Xu M. In situ process monitoring and automated multi-parameter evaluation using optical coherence tomography during extrusion-based bioprinting. Addit Manuf. 2021;47:102251. doi: 10.1016/j.addma.2021.102251

[137] Wang L, Xu M, Zhang L, Zhou Q, Luo L. Automated quantitative assessment of three-dimensional bioprinted hydrogel scaffolds using optical coherence tomography. Biomed Opt Express. 2016;7(3):894. doi: 10.1364/BOE.7.000894

[138] Schmieg B, Brandt N, Schnepp VJ, et al. Structured Data Storage for Data-Driven Process Optimisation in Bioprinting. Appl Sci.2022;12(15):7728. doi: 10.3390/app12157728

[139] Yu C, Jiang J. A perspective on using machine learning in 3D bioprinting. Int J Bioprint. 2020;6(1):253. doi: 10.18063/ijb.v6i1.253

[140] An J, Chua CK, Mironov V. Application of Machine Learning in 3D Bioprinting: Focus on Development of Big Data and Digital Twin. Int J Bioprint. 2021;7(1):342. doi: 10.18063/ijb.v7i1.342

[141] Jin Z, Zhang Z, Shao X, Gu GX. Monitoring Anomalies in 3D Bioprinting with Deep Neural Networks. ACS Biomater Sci Eng. 2021;9(7):3945-3952. doi: 10.1021/acsbiomaterials.0c01761

[142] Zhang Z, Zhou X, Fang Y, Xiong Z, Zhang T. AI-driven 3D bioprinting for regenerative medicine: From bench to bedside. Bioact Mater. 2025;45:201-230. doi: 10.1016/j.bioactmat.2024.11.021

[143] Fu Z, Angeline V, Sun W. Evaluation of Printing Parameters on 3D Extrusion Printing of Pluronic Hydrogels and Machine Learning Guided Parameter Recommendation. Int J Bioprint. 2021;7(4):434. doi: 10.18063/IJB.V7I4.434

[144] Ruberu K, Senadeera M, Rana S, et al. Coupling machine learning with 3D bioprinting to fast track optimisation of extrusion printing. Appl Mater Today. 2021;22:100914. doi: 10.1016/j.apmt.2020.100914

[145] Bonatti AF, Vozzi G, Chua CK, De Maria C. A Deep Learning Quality Control Loop of the Extrusion-based Bioprinting Process. Int J Bioprint. 2022;8(4):620. doi: 10.18063/ijb.v8i4.620

[146] Singh S, Choudhury D, Yu F, Mironov V, Naing MW. In situ bioprinting–Bioprinting from benchside to bedside? Acta Biomater. 2020;101:14-25. doi: 10.1016/j.actbio.2019.08.045

[147] Wang M, He J, Liu Y, Li M, Li D, Jin Z. The trend towards in vivo bioprinting. Int J Bioprint. 2015;1(1):15-26. doi: 10.18063/IJB.2015.01.001

[148] Sawkins MJ, Shakesheff KM, Bonassar LJ, Kirkham GR. 3D cell and scaffold patterning strategies in tissue engineering. Recent Pat Biomed Eng. 2013;6(1):3-21. doi: 10.2174/1874764711306010003

[149] Yoo D. New paradigms in internal architecture design and freeform fabrication of tissue engineering porous scaffolds. Med Eng Phys. 2012;34(6):762-776. doi: 10.1016/j.medengphy.2012.05.008

[150] Kuijer R, Jansen EJP, Emans PJ, et al. Assessing infection risk in implanted tissue-engineered devices. Biomaterials. 2007;28(34):5148-5154. doi: 10.1016/j.biomaterials.2007.06.003

[151] Ratcliffe A, Niklason LE. Bioreactors and bioprocessing for tissue engineering. Ann N Y Acad Sci. 2002;961:210-215. doi: 10.1111/j.1749-6632.2002.tb03087.x

[152] Ozbolat IT. Bioprinting scale-up tissue and organ constructs for transplantation. Trends Biotechnol. 2015;33(7):395-400. doi: 10.1016/j.tibtech.2015.04.005

[153] Ozbolat IT, Yu Y. Bioprinting toward organ fabrication: Challenges and future trends. IEEE Trans Biomed Eng. 2013;60(3):691-699. doi: 10.1109/TBME.2013.2243912

[154] Kajbafzadeh AM, Sabetkish S, Sabetkish N, et al. In-vivo trachea regeneration: fabrication of a tissue-engineered trachea in nude mice using the body as a natural bioreactor. Surg Today. 2015;45(8):1040-1048. doi: 10.1007/s00595-014-0993-2

[155] Jana T, Khabbaz E, Bush CM, et al. The body as a living bioreactor: A feasibility study of pedicle flaps for tracheal transplantation. Eur Arch Oto-Rhino-Laryngol. 2013;270(1):181-186. doi: 10.1007/s00405-012-2105-5

[156] Naujokat H, Acil Y, Gulses A, Birkenfeld F, Wiltfang J. Man as a living bioreactor: Long-term histological aspects of a mandibular replacement engineered in the patient’s own body. Int J Oral Maxillofac Surg. 2018;47(11):1481-1487. doi: 10.1016/j.ijom.2018.05.006

[157] Ashammakhi N, Ahadian S, Pountos I, et al. In situ three dimensional printing for reparative and regenerative therapy. Biomed Microdevices. 2019;21(2):1-6. doi: 10.1007/s10544-019-0372-2

[158] Hakimi N, Cheng R, Leng L, et al. Handheld skin printer: in situ formation of planar biomaterials and tissues. Lab Chip. 2018;18(10):1440-1451. doi: 10.1039/C7LC01236E

[159] Di Bella C, Duchi S, O’Connell CD, et al. In situ handheld three‐dimensional bioprinting for cartilage regeneration. J Tissue Eng Regen Med. 2018;12(3):611-621. doi: 10.1002/term.2476

[160] Keriquel V, Guillemot F, Arnault I, et al. In vivo bioprinting for computer- and robotic-assisted medical intervention: Preliminary study in mice. Biofabrication. 2010;2(1). doi: 10.1088/1758-5082/2/1/014101

[161] De Maria C, Vozzi G, Moroni L. Multimaterial, heterogeneous, and multicellular three-dimensional bioprinting. MRS Bull. 2017;42(8):578-584. doi: 10.1557/mrs.2017.165

[162] Feinberg AW, Miller JS. Progress in three-dimensional bioprinting. MRS Bull. 2017;42(8):557-562. doi: 10.1557/mrs.2017.166

[163] Fortunato GM, Rossi G, Bonatti AF, et al. Robotic platform and path planning algorithm for in situ bioprinting. Bioprinting. 2021;22:e00139. doi: 10.1016/j.bprint.2021.e00139

[164] Fortunato GM, Nicoletta M, Batoni E, Vozzi G, De Maria C. A fully automatic non-planar slicing algorithm for the additive manufacturing of complex geometries. Addit Manuf. 2023;69:103541. doi: 10.1016/j.addma.2023.103541

[165] Wu Y, Ravnic DJ, Ozbolat IT. Intraoperative Bioprinting: Repairing Tissues and Organs in a Surgical Setting. Trends Biotechnol. 2020;38(6):594-605. doi: 10.1016/j.tibtech.2020.01.004

[166] Cendrero AM, Fortunato GM, Munoz-Guijosa JM, De Maria C, Lantada AD. Benefits of non-planar printing strategies towards eco-efficient 3D printing. Sustainability. 2021;13(4):1599. doi: 10.3390/su13041599

[167] O’Neill JJ, Johnson RA, Dockter RL, Kowalewski TM. 3D bioprinting directly onto moving human anatomy. In: Proceedings of the 2017 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS). IEEE; 2017:934-940. doi: 10.1109/iros.2017.8202257

[168] Fortunato GM, Bonatti AF, Batoni E, Macaluso R, Vozzi G, De Maria C. Motion compensation system for robotic based in situ bioprinting to balance patient physiological movements. Bioprinting. 2022;28:e00248. doi: 10.1016/j.bprint.2022.e00248

[169] Li X, Lian Q, Li D, Xin H, Jia S. Development of a robotic arm based hydrogel additive manufacturing system for in-situ printing. Appl Sci. 2017;7(1). doi: 10.3390/app7010073

[170] Albanna M, Binder KW, Murphy S V. , et al. In Situ Bioprinting of Autologous Skin Cells Accelerates Wound Healing of Extensive Excisional Full-Thickness Wounds. Sci Rep. 2019;9(1):1-15. doi: 10.1038/s41598-018-38366-w

[171] Ma K, Zhao T, Yang L, et al. Application of robotic-assisted in situ 3D printing in cartilage regeneration with HAMA hydrogel: An in vivo study. J Adv Res. 2020;23:123-132. doi: 10.1016/j.jare.2020.01.010

[172] Fortunato GM, Batoni E, Bonatti AF, Vozzi G, De Maria C. Surface reconstruction and tissue recognition for robotic based in situ bioprinting. Bioprinting. 2022;26:e00195. doi: 10.1016/j.bprint.2022.e00195

[173] Fortunato GM, Bonatti AF, Micalizzi S, Chiesa I, Batoni E, Acutis A De. In Situ Bioprinting—Current Applications and Future Challenges. In: Additive Manufacturing in Biomedical Applications. 2022;23A:225-236.doi: 10.31399/asm.hb.v23A.a0006890

[174] Fortunato GM, Sigismondi S, Nicoletta M, et al. Analysis of the Robotic-Based In Situ Bioprinting Workflow for the Regeneration of Damaged Tissues through a Case Study. Bioengineering. 2023;10(5):560. doi: 10.3390/bioengineering10050560

[175] Zhu Z, Guo SZ, Hirdler T, et al. 3D Printed Functional and Biological Materials on Moving Freeform Surfaces. Adv Mater. 2018;30(23). doi: 10.1002/adma.201707495

[176] Zhu Z, Park HS, Mcalpine MC. 3D printed deformable sensors. Sci Adv. 2020;6(25):5575-5592. doi: 10.1126/sciadv.aba5575

[177] Guerra A, Davani S, Usai C, Jungst T, Boutopoulos C, Fortunato GM. High-accuracy real-time controlled robotic based bioprinting onto unknown and moving surfaces. Int J Adv Manuf Technol. 2025;141(3-4):1619-1634. doi: 10.1007/s00170-025-16810-2

[178] Zhao W, Xu T. Preliminary engineering for in situ in vivo bioprinting: A novel micro bioprinting platform for in situ in vivo bioprinting at a gastric wound site. Biofabrication. 2020;12(4):045020. doi: 10.1088/1758-5090/aba4ff

[179] Thai MT, Phan PT, Hoang TT, Low H, Lovell NH, Do TN. Design, fabrication, and hysteresis modeling of soft microtubule artificial muscle (smam) for medical applications. IEEE Robot Autom Lett. 2021;6(3):5089-5096. doi: 10.1109/LRA.2021.3072599

[180] Hu J, Guo L, Gu W, et al. Binocular Vision-Assisted Magnetic Soft Catheter Robot System for Minimally Invasive in-Situ Bioprinting. IEEE Robot Autom Lett. 2024;9(12):11130-11137. doi: 10.1109/LRA.2024.3474552

[181] Rohr S, Scholly DM, Kleber AG. Patterned growth of neonatal rat heart cells in culture. Morphological and electrophysiological characterization. Circ Res. 1991;68(1):114-130. doi: 10.1161/01.res.68.1.114

[182] Rahmani Dabbagh S, Rezapour Sarabi M, Birtek MT, Mustafaoglu N, Zhang YS, Tasoglu S. 3D bioprinted organon‐ chips. Aggregate. 2022;4(1). doi: 10.1002/agt2.197

[183] Rajeshkumar G, Vishnupriyan R, Selvadeepak S. Tissue Mimicking Material an Idealized Tissue Model for ClinicalApplications: A Review. Mater Today Proc. 2020;22:2696-2703. doi: 10.1016/j.matpr.2020.03.400

[184] Mazrouei R, Velasco V, Esfandyarpour R. 3D-bioprinted all-inclusive bioanalytical platforms for cell studies. Sci Rep. 2020;10(1). doi: 10.1038/s41598-020-71452-6

[185] Xie M, Gao Q, Fu J, Chen Z, He Y. Bioprinting of novel 3D tumor array chip for drug screening. Biodes Manuf. 2020;3(3):175-188. doi: 10.1007/s42242-020-00078-4

[186] Cao X, Ashfaq R, Cheng F, et al. A Tumor-on-a-Chip System with Bioprinted Blood and Lymphatic Vessel Pair. Adv Funct Mater. 2019;29(31):1807173. doi: 10.1002/adfm.201807173

[187] Thakare K, Jerpseth L, Pei Z, Elwany A, Quek F, Qin H. Bioprinting of organ-on-chip systems: A literature review from a manufacturing perspective. J Manuf Mater Process. 2021;5(3). doi: 10.3390/JMMP5030091

[188] Knowlton S, Yenilmez B, Tasoglu S. Towards Single-Step Biofabrication of Organs on a Chip via 3D Printing. Trends Biotechnol. 2016;34(9):685-688. doi: 10.1016/j.tibtech.2016.06.005

[189] Zheng F, Fu F, Cheng Y, Wang C, Zhao Y, Gu Z. Organon-a-Chip Systems: Microengineering to Biomimic Living Systems. Small. 2016;12(17):2253-2282. doi: 10.1002/smll.201503208

[190] Yu F, Choudhury D. Microfluidic bioprinting for organ-ona- chip models. Drug Discov Today. 2019;24(6):1248-1257. doi: 10.1016/j.drudis.2019.03.025

[191] Huh D, Matthews BD, Mammoto A, Montoya-Zavala M, Yuan Hsin H, Ingber DE. Reconstituting Organ-Level Lung Functions on a Chip. Science. 2010;328(5986):1662. doi: 10.1126/science.1188302

[192] Aleman J, Kilic T, Mille LS, Shin SR, Zhang YS. Microfluidic integration of regeneratable electrochemical affinity-based biosensors for continual monitoring of organ-on-a-chip devices. Nat Protoc. 2021;16(5):2564-2593. doi: 10.1038/s41596-021-00511-7

[193] Polat A, Hassan S, Yildirim I, et al. A miniaturized optical tomography platform for volumetric imaging of engineered living systems. Lab Chip. 2019;19(4):550-561. doi: 10.1039/c8lc01190g

[194] Avci H, Guzel FD, Erol S, Akpek A. Recent advances in organ-on-a-chip technologies and future challenges: a review. Turk J Chem. 2018;42(3):587-610. doi: 10.3906/kim-1611-35

[195] Fetah K, Tebon P, Goudie MJ, et al. The emergence of 3D bioprinting in organ-on-chip systems. Prog Biomed Eng. 2019;1(1):012001. doi: 10.1088/2516-1091/ab23df

[196] Bhatia SN, Ingber DE. Microfluidic organs-on-chips. Nat Biotechnol. 2014;32(8):760-772.doi: 10.1038/nbt.2989

[197] Ozdalgic B, Ustun M, Dabbagh SR, Haznedaroglu BZ, Kiraz A, Tasoglu S. Microfluidics for microalgal biotechnology. Biotechnol Bioeng. 2021;118(4):1545-1563. doi: 10.1002/bit.27669

[198] Lee H, Cho DW. One-step fabrication of an organ-ona-chip with spatial heterogeneity using a 3D bioprinting technology. Lab Chip. 2016;16(14):2618-2625. doi: 10.1039/C6LC00450D

[199] Ke D, Yi H, Est-Witte S, et al. Bioprinted trachea constructs with patient-matched design, mechanical and biological properties. Biofabrication. 2020;12(1):015022. doi: 10.1088/1758-5090/ab5354

[200] Rothbauer M, Eilenberger C, Spitz S, et al. Recent Advances in Additive Manufacturing and 3D Bioprinting for Organs-On-A-Chip and Microphysiological Systems. Front Bioeng Biotechnol. 2022;10:837087. doi: 10.3389/fbioe.2022.837087

[201] Gruene M, Unger C, Koch L, Deiwick A, Chichkov B. Dispensing pico to nanolitre of a natural hydrogel by laser assisted bioprinting. Biomed Eng Online. 2011;10. doi: 10.1186/1475-925X-10-19

[202] Miri AK, Mirzaee I, Hassan S, et al. Effective Bioprinting Resolution in Tissue Model Fabrication. Lab Chip. 2019;19(11):2019. doi: 10.1039/C8LC01037D

[203] Kim HJ, Lee J, Choi JH, Bahinski A, Ingber DE. Co-culture of Living Microbiome with Microengineered Human Intestinal Villi in a Gut-on-a-Chip Microfluidic Device. J Vis Exp. 2016;2016(114):54344. doi: 10.3791/54344

[204] Lin NYC, Homan KA, Robinson SS, et al. Renal reabsorption in 3D vascularized proximal tubule models. Proc Natl Acad Sci USA. 2019;116(12):5399-5404. doi: 10.1073/pnas.1815208116

[205] Lind JU, Busbee TA, Valentine AD, et al. Instrumented cardiac microphysiological devices via multimaterial three dimensional printing. Nat Mater. 2017;16(3):303-308. doi: 10.1038/nmat4782

[206] Saygili E, Dogan-Gurbuz AA, Yesil-Celiktas O, Draz MS. 3D bioprinting: A powerful tool to leverage tissue engineering and microbial systems. Bioprinting. 2020;18. doi: 10.1016/j.bprint.2019.e00071

[207] Park JY, Ryu H, Lee B, et al. Development of a functional airway-on-a-chip by 3D cell printing. Biofabrication. 2019;11(1). doi: 10.1088/1758-5090/aae545

[208] Kim W, Kim G. Intestinal Villi Model with Blood Capillaries Fabricated Using Collagen-Based Bioink and Dual-Cell-Printing Process. ACS Appl Mater Interfaces. 2018;10(48):41185-41196. doi: 10.1021/acsami.8b17410

[209] Lee JH, Gu Y, Wang H, Lee WY. Microfluidic 3D bone tissue model for high-throughput evaluation of wound healing and infection-preventing biomaterials. Biomaterials. 2012;33(4):999-1006. doi: 10.1016/j.biomaterials.2011.10.036

[210] Zhang YS, Davoudi F, Walch P, et al. Bioprinted thrombosis on- a-chip. Lab Chip. 2016;16(21):4097-4105. doi: 10.1039/C6LC00380J

[211] Wang YI, Erbil Abaci H, Shuler Nancy E ML. Microfluidic blood-brain barrier model provides in vivo-like barrier properties for drug permeability screening. Biotechnol Bioeng. 2017;114:184-194. doi: 10.1002/bit.26045

[212] Kaya M, Ahishali B. Basic physiology of the blood-brain barrier in health and disease: a brief overview. Tissue Barriers. 2020;9(1):1840913. doi: 10.1080/21688370.2020.1840913

[213] Vijayavenkataraman S, Yan WC, Lu WF, Wang CH, Fuh JYH. 3D bioprinting of tissues and organs for regenerative medicine. Adv Drug Deliv Rev. 2018;132:296-332. doi: 10.1016/j.addr.2018.07.004

[214] Yang GH, Yeo M, Koo YW, Kim GH. 4D Bioprinting: Technological Advances in Biofabrication. Macromol Biosci. 2019;19(5). doi: 10.1002/mabi.201800441

[215] Gao B, Yang Q, Zhao X, Jin G, Ma Y, Xu F. 4D Bioprinting for Biomedical Applications. Trends Biotechnol. 2016;34(9):746-756. doi: 10.1016/j.tibtech.2016.03.004

[216] Tibbits S. 4D printing: Multi‐material shape change. Archit Des. 2014;84(1):116-121.doi: 10.1002/ad.1710

[217] Bodaghi M, Noroozi R, Zolfagharian A, Fotouhi M, Norouzi S. 4D printing self-morphing structures. Materials.

[218] Agarwal T, Hann SY, Chiesa I, et al. 4D printing in biomedical applications: emerging trends and technologies. J Mater Chem B. 2021;9(37):7608-7632. doi: 10.1039/d1tb01335a

[219] Abolhassani S, fattahi R, Safshekan F, Saremi J, Hasanzadeh E. Advances in 4D Bioprinting: The Next Frontier in Regenerative Medicine and Tissue Engineering Applications. Adv Healthc Mater. 2025;14(4). doi: 10.1002/adhm.202403065

[220] Miao S, Castro N, Nowicki M, et al. 4D printing of polymeric materials for tissue and organ regeneration. Mater Today. 2017;20(10):577-591. doi: 10.1016/j.mattod.2017.06.005

[221] Kuang X, Roach DJ, Wu J, et al. Advances in 4D Printing: Materials and Applications. Adv Funct Mater. 2019;29(2). doi: 10.1002/adfm.201805290

[222] Shafranek RT, Millik SC, Smith PT, Lee CU, Boydston AJ, Nelson A. Stimuli-responsive materials in additive manufacturing. Prog Polym Sci. 2019;93:36-67. doi: 10.1016/j.progpolymsci.2019.03.002

[223] Lui YS, Sow WT, Tan LP, Wu Y, Lai Y, Li H. 4D printing and stimuli-responsive materials in biomedical aspects. Acta Biomater. 2019;92:19-36. doi: 10.1016/j.actbio.2019.05.005

[224] Javaid M, Haleem A. 4D printing applications in medical field: A brief review. Clin Epidemiol Glob Health. 2019;7(3):317-321. doi: 10.1016/j.cegh.2018.09.007

[225] Bittolo Bon S, Chiesa I, Morselli D, et al. Printable smart 3D architectures of regenerated silk on poly(3-hydroxybutyrateco-3-hydroxyvalerate). Mater Des. 2021;201:109492. doi: 10.1016/j.matdes.2021.109492

[226] De Maria C, Chiesa I, Morselli D, et al. Biomimetic Tendrils by Four Dimensional Printing Bimorph Springs with Torsion and Contraction Properties Based on Bio-Compatible Graphene/Silk Fibroin and Poly(3-Hydroxybutyrate-co-3- Hydroxyvalerate). Adv Funct Mater. 2021;31(52). doi: 10.1002/adfm.202105665

[227] Lai J, Wang M. Developments of additive manufacturing and 5D printing in tissue engineering. J Mater Res. 2023;38(21):4692-4725. doi: 10.1557/s43578-023-01193-5

[228] Li D, He J, Wang L, Gao L, Lu B. 5D Printing-Fabrication of Biological Function Tissue. China Mech Eng. 2020;31(1):83-88. doi: 10.3969/j.issn.1004-132X.2020.01.009

[229] Groll J, Boland T, Blunk T, et al. Biofabrication: Reappraising the definition of an evolving field. Biofabrication. 2016;8(1):013001. doi: 10.1088/1758-5090/8/1/013001

[230] Sexton ZA, Hudson AR, Herrmann JE, et al. Rapid model guided design of organ-scale synthetic vasculature for biomanufacturing. Science. 2025;388(6752):1198-1204. doi: 10.1126/science.adj6152

[231] Vidler C, Halwes M, Kolesnik K, et al. Dynamic interface printing. Nature. 2024;634(8036):1096-1102. doi: 10.1038/s41586-024-08077-6

[232] Florczak S, Grosbacher G, Ribezzi D, Longoni A, Gueye M, Grandidier E, et al. Adaptive and context-aware volumetric printing. Nature. 2025;645(8079):108-114. doi: 10.1038/s41586-025-09436-7

[233] Pushing the boundaries of biofabrication. Nat Rev Bioeng.2025;3(2):103.doi: 10.1038/s44222-025-00278-6

[234] Filippi M, Mekkattu M, Katzschmann RK. Sustainable biofabrication: from bioprinting to AI-driven predictive methods. Trends Biotechnol. 2025;43(2):290-303. doi: 10.1016/j.tibtech.2024.07.002