Mechanisms of pore formation in hydrogel scaffolds textured by freeze-drying
| العنوان: | Mechanisms of pore formation in hydrogel scaffolds textured by freeze-drying |
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| المؤلفون: | Fabrice Barou, Hervé Duval, Jérôme Grenier, Bertrand David, Didier Letourneur, Pin Lv |
| المساهمون: | Laboratoire de Génie des Procédés et Matériaux - EA 4038 (LGPM), CentraleSupélec, Laboratoire de mécanique des sols, structures et matériaux (MSSMat), CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Recherche Vasculaire Translationnelle (LVTS (UMR_S_1148 / U1148)), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Paris Cité (UPCité)-Université Sorbonne Paris Nord, Géosciences Montpellier, Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA), Grenier, Jérôme, Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Paris (UP)-Université Sorbonne Paris Nord, Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Université des Antilles (UA)-Centre National de la Recherche Scientifique (CNRS), Univ Paris Diderot, INSERM, Lab Vasc Translat Sci U1148, Paris, France |
| المصدر: | Acta Biomaterialia Acta Biomaterialia, 2019, 94, pp.195-203. ⟨10.1016/j.actbio.2019.05.070⟩ Acta Biomaterialia, Elsevier, 2019, 94, pp.195-203. ⟨10.1016/j.actbio.2019.05.070⟩ |
| بيانات النشر: | HAL CCSD, 2019. |
| سنة النشر: | 2019 |
| مصطلحات موضوعية: | MESH: 3T3 Cells, Polymers, [SDV]Life Sciences [q-bio], MESH: Freeze Drying, Nucleation, Biocompatible Materials, MESH: Solvents, 02 engineering and technology, Biochemistry, MESH: Tissue Engineering, Mice, Tissue engineering, MESH: Biocompatible Materials, Freezing, MESH: Tissue Scaffolds, MESH: Animals, chemistry.chemical_classification, 3D cell culture, Aqueous solution, Tissue Scaffolds, Hydrogels, General Medicine, Polymer, 3T3 Cells, MESH: Bone and Bones, 021001 nanoscience & nanotechnology, Grain size, MESH: Polymers, Cross-Linking Reagents, Self-healing hydrogels, 0210 nano-technology, Rheology, Porosity, Polysaccharide-based hydrogel, Biotechnology, MESH: Hydrogels, [CHIM.POLY] Chemical Sciences/Polymers, Materials science, MESH: Microscopy, Electron, Scanning, [SPI.GPROC] Engineering Sciences [physics]/Chemical and Process Engineering, Polysaccharide-based, MESH: Cross-Linking Reagents, 0206 medical engineering, Biomedical Engineering, Porous scaffolds, Bone and Bones, Biomaterials, MESH: Porosity, Polysaccharides, MESH: Rheology, Animals, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, [SDV.IB.BIO]Life Sciences [q-bio]/Bioengineering/Biomaterials, Molecular Biology, Ice-templating, MESH: Mice, Tissue Engineering, technology, industry, and agriculture, 020601 biomedical engineering, [SDV.IB.BIO] Life Sciences [q-bio]/Bioengineering/Biomaterials, Hydrogel, Freeze Drying, MESH: Polysaccharides, [CHIM.POLY]Chemical Sciences/Polymers, Chemical engineering, chemistry, Ionic strength, Freeze-drying, Microscopy, Electron, Scanning, Solvents, MESH: Freezing |
| الوصف: | Whereas freeze-drying is a widely used method to produce porous hydrogel scaffolds, the mechanisms of pore formation involved in this process remained poorly characterized. To explore this, we focused on a cross-linked polysaccharide-based hydrogel developed for bone tissue engineering. Scaffolds were first swollen in 0.025% NaCl then freeze-dried at low cooling rate, i.e. −0.1 °C min−1, and finally swollen in aqueous solvents of increasing ionic strength. We found that scaffold’s porous structure is strongly conditioned by the nucleation of ice. Electron cryo-microscopy of frozen scaffolds demonstrates that each pore results from the growth of one to a few ice grains. Most crystals were formed by secondary nucleation since very few nucleating sites were initially present in each scaffold (0.1 nuclei cm−3 °C−1). The polymer chains are rejected in the intergranular space and form a macro-network. Its characteristic length scale coincides with the ice grain size (160 μ m ) and is several orders of magnitude greater than the mesh size (90 nm) of the cross-linked network. After sublimation, the ice grains are replaced by macro-pores of 280 μ m mean size and the resulting dry structure is highly porous, i.e. 93%, as measured by high-resolution X-ray tomography. In the swollen state, the scaffold mean pore size decreases in aqueous solvent of increasing ionic strength (120 µm in 0.025% NaCl and 54 µm in DBPS) but the porosity remains the same, i.e. 29% regardless of the solvent. Finally, cell seeding of dried scaffolds demonstrates that the pores are adequately interconnected to allow homogenous cell distribution. Statement of Significance The fabrication of hydrogel scaffolds is an important research area in tissue engineering. Hydrogels are textured to provide a 3D-framework that is favorable for cell proliferation and/or differentiation. Optimum hydrogel pore size depends on its biological application. Producing porous hydrogels is commonly achieved through freeze-drying. However, the mechanisms of pore formation remain to be fully understood. We carefully analyzed scaffolds of a cross-linked polysaccharide-based hydrogel developed for bone tissue engineering, using state-of-the-art microscopic techniques. Our experimental results evidenced the shaping of hydrogel during the freezing step, through a specific ice-templating mechanism. These findings will guide the strategies for controlling the porous structure of hydrogel scaffolds. |
| وصف الملف: | application/pdf |
| اللغة: | English |
| تدمد: | 1742-7061 |
| DOI: | 10.1016/j.actbio.2019.05.070⟩ |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::bf6d615335d9fb503303c7c53fe9d53d https://hal.science/hal-02144830 |
| Rights: | OPEN |
| رقم الانضمام: | edsair.doi.dedup.....bf6d615335d9fb503303c7c53fe9d53d |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 17427061 |
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| DOI: | 10.1016/j.actbio.2019.05.070⟩ |