Abstract: Hydrogels, owing to their porous network structure resembling the extracellular matrix (ECM), have become essential scaffold materials in the field of cartilage tissue engineering. Among them, gelatin methacrylate (GelMA) hydrogels are widely used in bioink development due to their excellent biocompatibility, biodegradability, and tunable photo-crosslinking properties. However, the high biocompatibility of pure GelMA often comes at the cost of mechanical strength, limiting its applicability in cartilage regeneration. To overcome this trade-off, this study developed composite bioinks based on GelMA, silk fibroin (SF), and polyethylene oxide (PEO) for fabricating porous hydrogel scaffolds, which were then systematically characterized in terms of morphology, porosity, hydrophilicity, mechanical strength, rheological behavior, printability, and cytocompatibility. In this design, PEO serves as a porogen to generate highly porous structures (porosity up to 88%), while SF compensates for the mechanical loss caused by PEO, enabling the scaffold to retain a compression strength of up to 29.10 kPa. Among the tested formulations, the 10% GelMA/1% SF/1.5% PEO (1%=0.01 g/mL) bioink exhibited excellent printability, mechanical integrity, and cytocompatibility, and it supported a robust deposition of collagen II and aggrecan by chondrocytes after printing. This work provides a versatile strategy for balancing the biocompatibility and mechanical robustness in bioinks, offering a promising platform for next-generation cartilage tissue engineering scaffolds.

一种具有生物相容性和机械强度的新型多组分协同生物墨水用于促进软骨再生

[1]AppelEA, TibbittMW, WebberMJ, et al., 2015. Self-assembled hydrogels utilizing polymer‒nanoparticle interactions. Nat Commun, 6:6295.

[2]ArguchinskayaNV, IsaevaEV, KiselAA, et al., 2023. Properties and printability of the synthesized hydrogel based on GeLMA. Int J Mol Sci, 24(3):2121.

[3]BaiL, JingYY, ReisRL, et al., 2025. Organoid research: theory, technology, and therapeutics. Organoid Res, 1(1):025040007.

[4]BrunelLG, HullSM, HeilshornSC, 2022. Engineered assistive materials for 3D bioprinting: support baths and sacrificial inks. Biofabrication, 14(3):032001.

[5]CaoYY, ChengP, SangSB, et al., 2021. 3D printed PCL/GelMA biphasic scaffold boosts cartilage regeneration using co-culture of mesenchymal stem cells and chondrocytes: in vivo study. Mater Des, 210:110065.

[6]ChenSS, WangY, LaiJH, et al., 2023. Structure and properties of gelatin methacryloyl (GelMA) synthesized in different reaction systems. Biomacromolecules, 24(6):2928-2941.

[7]de GirolamoL, RagniE, CucchiariniM, et al., 2019. Cells, soluble factors and matrix harmonically play the concert of allograft integration. Knee Surg Sports Traumatol Arthrosc, 27(6):1717-1725.

[8]FindeisenS, GräfeN, SchwilkM, et al., 2023. Use of autologous bone graft with bioactive glass as a bone substitute in the treatment of large-sized bone defects of the femur and tibia. J Pers Med, 13(12):1644.

[9]HeP, ZhaoYB, WangB, et al., 2024. A biodegradable magnesium phosphate cement incorporating chitosan and rhBMP-2 designed for bone defect repair. J Orthop Transl, 49:167-180.

[10]HouMZ, ZhangYJ, LiuY, et al., 2023. Biomimetic melatonin-loaded silk fibroin/GelMA scaffold strengthens cartilage repair through retrieval of mitochondrial functions. J Mater Sci Technol, 146:102-112.

[11]HuangDY, LiYH, MaZH, et al., 2023. Collagen hydrogel viscoelasticity regulates MSC chondrogenesis in a ROCK-dependent manner. Sci Adv, 9(6):eade9497.

[12]IsrebA, BajK, WojszM, et al., 2019. 3D printed oral theophylline doses with innovative ‘radiator-like’ design: impact of polyethylene oxide (PEO) molecular weight. Int J Pharm, 564:98-105.

[13]JeongSH, HiemstraJ, BlokzijlPV, et al., 2024. An oxygenating colloidal bioink for the engineering of biomimetic tissue constructs. Bio-Des Manuf, 7(3):240-261.

[14]JiaLT, HuaYJ, ZengJS, et al., 2022. Bioprinting and regeneration of auricular cartilage using a bioactive bioink based on microporous photocrosslinkable acellular cartilage matrix. Bioact Mater, 16:66-81.

[15]LeeSS, DuXY, KimI, et al., 2022. Scaffolds for bone-tissue engineering. Matter, 5(9):2722-2759.

[16]LiM, SunL, LiuZX, et al., 2023. 3D bioprinting of heterogeneous tissue-engineered skin containing human dermal fibroblasts and keratinocytes. Biomater Sci, 11(7):2461-2477.

[17]LiM, LiuZX, ShenZZ, et al., 2024. A heparin-functionalized bioink with sustained delivery of vascular endothelial growth factor for 3D bioprinting of prevascularized dermal constructs. Int J Biol Macromol, 262:130075.

[18]LiMX, SongP, WangWZ, et al., 2022. Preparation and characterization of biomimetic gradient multi-layer cell-laden scaffolds for osteochondral integrated repair. J Mater Chem B, 10(22):4172-4188.

[19]LiuM, ZengX, MaC, et al., 2017. Injectable hydrogels for cartilage and bone tissue engineering. Bone Res, 5:17014.

[20]LiuY, YuL, ZhangD, et al., 2022. Manufacture and preliminary evaluation of acellular tooth roots as allografts for alveolar ridge augmentation. J Biomed Mater Res A, 110:122-130.

[21]LuXT, SongWJ, SunXM, et al., 2022. Porous hydrogel constructs based on methacrylated gelatin/polyethylene oxide for corneal stromal regeneration. Mater Today Commun, 32:104071.

[22]MaWP, LuHX, XiaoY, et al., 2025. Advancing organoid development with 3D bioprinting. Organoid Res, 1(1):025040004.

[23]ManoharSS, DasC, KakatiV, 2024. Bone tissue engineering scaffolds: materials and methods. 3D Print Addit Manuf, 11(1):347-362.

[24]MüllerSA, BargA, VavkenP, et al., 2016. Autograft versus sterilized allograft for lateral calcaneal lengthening osteotomies. Medicine, 95(30):e4343.

[25]NgWL, HuangX, ShkolnikovV, et al., 2023. Polyvinylpyrrolidone-based bioink: influence of bioink properties on printing performance and cell proliferation during inkjet-based bioprinting. Bio-Des Manuf, 6(6):676-690.

[26]NingLQ, MehtaR, CaoC, et al., 2020. Embedded 3D bioprinting of gelatin methacryloyl-based constructs with highly tunable structural fidelity. ACS Appl Mater Interfaces, 12(40):44563-44577.

[27]PattanashettiNA, VianaT, AlvesN, et al., 2020. Development of novel 3D scaffolds using BioExtruder by varying the content of hydroxyapatite and silica in PCL matrix for bone tissue engineering. J Polym Res, 27(4):87.

[28]SangSB, MaoXJ, CaoYY, et al., 2023. 3D bioprinting using synovium-derived MSC-laden photo-cross-linked ECM bioink for cartilage regeneration. ACS Appl Mater Interfaces, 15(7):8895-8913.

[29]SeymourAJ, ShinS, HeilshornSC, 2021. 3D printing of microgel scaffolds with tunable void fraction to promote cell infiltration. Adv Healthc Mater, 10(18):2100644.

[30]SharifiS, SharifiH, AkbariA, et al., 2021. Systematic optimization of visible light-induced crosslinking conditions of gelatin methacryloyl (GelMA). Sci Rep, 11:23276.

[31]ShiXH, BaiY, HeXM, et al., 2022. Shaoyao Gancao Decoction for limb dysfunction after fractures around the knee. Medicine, 101(11):e29051.

[32]TuchmanA, BrodkeDS, YoussefJA, et al., 2016. Iliac crest bone graft versus local autograft or allograft for lumbar spinal fusion: a systematic review. Global Spine J, 6(6):592-606.

[33]VermaV, VermaP, KarS, et al., 2007. Fabrication of agar-gelatin hybrid scaffolds using a novel entrapment method for in vitro tissue engineering applications. Biotechnol Bioeng, 96(2):392-400.

[34]WangC, HuangW, ZhouY, et al., 2020. 3D printing of bone tissue engineering scaffolds. Bioact Mater, 5(1):82-91.

[35]WangWZ, ZhangBQ, LiMX, et al., 2021. 3D printing of PLA/n-HA composite scaffolds with customized mechanical properties and biological functions for bone tissue engineering. Compos Part B Eng, 224:109192.

[36]WangYT, HouY, HaoT, et al., 2024. Model construction and clinical therapeutic potential of engineered cardiac organoids for cardiovascular diseases. Biomater Transl, 5(4): 337-354.

[37]WangZ, WangX, HuangY, et al., 2024. Ca_v3.3-mediated endochondral ossification in a three-dimensional bioprinted GelMA hydrogel. Bio-Des Manuf, 7(6):983-999.

[38]XiaYL, WangHY, LiYH, et al., 2022. Engineered bone cement trigger bone defect regeneration. Front Mater, 9:929618.

[39]XieMJ, GaoQ, ZhaoHM, et al., 2019. Electro-assisted bioprinting of low-concentration GelMA microdroplets. Small, 15(4):1804216.

[40]XueNN, DingXF, HuangRZ, et al., 2022. Bone tissue engineering in the treatment of bone defects. Pharmaceuticals, 15(7):879.

[41]XueYM, KimHJ, LeeJ, et al., 2022. Co-electrospun silk fibroin and gelatin methacryloyl sheet seeded with mesenchymal stem cells for tendon regeneration. Small, 18(21):2107714.

[42]YangJR, HeHM, LiD, et al., 2023. Advanced strategies in the application of gelatin-based bioink for extrusion bioprinting. Bio-Des Manuf, 6(5):586-608.

[43]YiSL, LiuQ, LuoZY, et al., 2022. Micropore-forming gelatin methacryloyl (GelMA) bioink toolbox 2.0: designable tunability and adaptability for 3D bioprinting applications. Small, 18(25):2106357.

[44]YingGL, JiangN, MaharjanS, et al., 2018. Aqueous two-phase emulsion bioink-enabled 3D bioprinting of porous hydrogels. Adv Mater, 30(50):1805460.

[45]YuanX, ZhuW, YangZY, et al., 2024. Recent advances in 3D printing of smart scaffolds for bone tissue engineering and regeneration. Adv Mater, 36(34):2403641.

[46]ZhangLY, BiQ, ZhaoC, et al., 2020. Recent advances in biomaterials for the treatment of bone defects. Organogenesis, 16(4):113-125.

[47]ZhangYS, YuWH, 2025. Recent advances in bionic scaffolds for cartilage tissue engineering. Front Bioeng Biotechnol, 13:1625550.

[48]ZhangYW, LiZX, GuanJJ, et al., 2021. Hydrogel: a potential therapeutic material for bone tissue engineering. AIP Adv, 11(1):010701.

[49]ZhengKW, ZhengX, YuMZ, et al., 2023. BMSCs-seeded interpenetrating network GelMA/SF composite hydrogel for articular cartilage repair. J Funct Biomater, 14(1):39.