20.500.12556/DKUM-93938 The impact of temperature and the duration of freezing on a hydrogel used for a 3d-bioprinted in vitro skin model Skin bioprinting has the potential to revolutionize treatment approaches for injuries and surgical procedures, while also providing a valuable platform for assessing and screening cosmetic and pharmaceutical products. This technology offers key advantages, including flexibility and reproducibility, which enable the creation of complex, multilayered scaffolds that closely mimic the intricate microenvironment of native skin tissue. The development of an ideal hydrogel is critical for the successful bioprinting of these scaffolds with incorporated cells. In this study, we used a hydrogel formulation developed in our laboratory to fabricate a 3D-bioprinted skin model. The hydrogel composition was carefully selected based on its high compatibility with human skin cells, incorporating alginate, methyl cellulose, and nanofibrillated cellulose. One of the critical challenges in this process, particularly for its commercialization and large-scale production, is ensuring consistency with minimal batch-to-batch variations. To address this, we explored methods with which to preserve the physicochemical properties of the hydrogels, with a focus on freezing techniques. We validated the pre-frozen hydrogels’ printability, rheology, and mechanical and surface properties. Our results revealed that extended freezing times significantly reduced the viscosity of the formulations due to ice crystal formation, leading to a redistribution of the polymer chains. This reduction in viscosity resulted in a more challenging extrusion and increased macro- and microporosity of the hydrogels, as confirmed by nanoCT imaging. The increased porosity led to greater water uptake, swelling, compromised scaffold integrity, and altered degradation kinetics. The insights gained from this study lay a solid foundation for advancing the development of an in vitro skin model with promising applications in preclinical and clinical research. in vitro skin model 3D printing hydrogels preclinical and clinical medicine model kože in vitro 3D tiskanje hidrogeli predklinična in klinična medicina true false true MDPI AG Angleški jezik Slovenski jezik https://www.mdpi.com/journal/biomedicines © 2024 by the authors Članek v reviji 2025-07-26 03:13:56 2025-07-28 07:34:31 2025-07-29 03:11:46 0000-00-00 00:00:00 2024 0 0 str. 1-19 št. 9, št. članka 2028 let. 12 2024 0000-00-00 Zaloznikova Objavljeno NiDoloceno 2024-08-14 2024-09-03 2024-09-05 616.5 206685955 10.3390/biomedicines12092028 2227-9059 biomedicines-12-02028.pdf biomedicines-12-02028.pdf 1 7AE6305BF57B4C8CF96D1F0FEA8CD56E 7babb30aa501a24078fd1093bfd1fe4c96317591fd40b6a91311819306689a80 e53a3669-6b74-11f0-bb04-00155d000105 https://dk.um.si/Dokument.php?lang=slv&id=194250 https://www.mdpi.com/2227-9059/12/9/2028 1 ce09cd30-69bd-11f0-879b-00155d000105 https://dk.um.si/Dokument.php?lang=slv&id=194221 Medicinska fakulteta Fakulteta za strojništvo 0 0 0