Foster Olivia K, Hiscox Derek, Shaidani Sawnaz, Park Jean, Canas Ella, Jacobus Charlotte, Patten Riley, Kaplan David L
Department of Biomedical Engineering, Tufts University, Medford, Massachusetts, USA.
J Biomed Mater Res A. 2025 Jun;113(6):e37945. doi: 10.1002/jbm.a.37945.
Hydrogels prepared from natural polymers, such as silk fibroin, are useful in the field of tissue engineering due to their biocompatibility, biodegradability, and biological performance. However, poor mechanical properties can limit their broader utility. This study investigated reinforcing enzymatically crosslinked silk hydrogels with 130 nm silk nanoparticles (SNPs) to generate silk-silk composite materials with tunable strength and stiffness. The strength of the materials was dependent on SNP concentration, and hydrogels with Young's moduli of 14, 34, and 67 kPa were fabricated by adding no SNPs, 2 mg/mL SNPs, and 4 mg/mL SNPs, respectively. These methods were applied to silk bioinks using Freeform Reversible Embedding of Suspended Hydrogels (FRESH) 3D printing to fabricate complex 3D structures with control of elasticity and modulus. Cylinders with Young's moduli of 17, 35, and 58 kPa were obtained with no SNPs, 2 mg/mL SNPs, and 4 mg/mL SNPs, respectively. SNPs were also preloaded with epidermal growth factor (EGF), relevant for tissue development and wound healing, and sustained release was achieved for over 15 days when embedded in hydrogels. Pilot studies of dermal fibroblast encapsulation in SNP-reinforced silk hydrogels demonstrated cytocompatibility. Tunable silk hydrogels reinforced with SNPs provide application-specific scaffolding for a variety of biomaterial and tissue engineering applications.
由天然聚合物(如丝素蛋白)制备的水凝胶,因其生物相容性、生物可降解性和生物学性能,在组织工程领域具有重要应用价值。然而,较差的机械性能会限制其更广泛的应用。本研究探索了用130纳米的丝纳米颗粒(SNP)增强酶交联丝水凝胶,以制备强度和刚度可调的丝-丝复合材料。材料的强度取决于SNP浓度,分别通过添加0毫克/毫升SNP、2毫克/毫升SNP和4毫克/毫升SNP,制备出杨氏模量分别为14千帕、34千帕和67千帕的水凝胶。这些方法被应用于使用悬浮水凝胶的自由形式可逆嵌入(FRESH)3D打印的丝生物墨水,以制造具有弹性和模量可控的复杂3D结构。分别使用0毫克/毫升SNP、2毫克/毫升SNP和4毫克/毫升SNP,获得了杨氏模量分别为17千帕、35千帕和58千帕的圆柱体。SNP还预先负载了与组织发育和伤口愈合相关的表皮生长因子(EGF),当嵌入水凝胶时可实现超过15天的持续释放。对SNP增强丝水凝胶中真皮成纤维细胞封装的初步研究证明了细胞相容性。用SNP增强的可调丝水凝胶为各种生物材料和组织工程应用提供了特定应用的支架。