School of Engineering, Westlake University, Hangzhou, Zhejiang, 310030, China.
Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province, Instrumentation and Service Center for Molecular Sciences, Westlake University, Hangzhou, Zhejiang, 310024, China.
Adv Healthc Mater. 2023 Nov;12(28):e2301439. doi: 10.1002/adhm.202301439. Epub 2023 Sep 10.
Silk fibroin derived from the domesticated silkworm Bombyx mori is a protein-based biopolymer with low immunogenicity, intrinsic biodegradability, and tunable mechanical properties, showing great potential in biomedical applications. Using chemical modification to alter the primary structure of silk fibroin enables the expanded generation of new silk-based biomaterials. Inspired by the molecular structure of hyaluronic acid, which is enriched in carboxyl groups, an efficient method with scaling-up potential to achieve controlled carboxylation of silk fibroin to prepare silk acid (SA) is reported, and the biological properties of SA are further studied. The SA materials show tunable hydrophilicity and enzymatic degradation properties at different carboxylation degrees (CDs). Subcutaneous implantation in mice for up to 1 month reveals that the SA materials with a high CD present enhanced degradation while causing a mild foreign-body response, including a low inflammatory response and reduced fibrotic encapsulation. Immunofluorescence analysis further indicates that the SA materials show pro-angiogenesis properties and promote M2-type macrophage polarization to facilitate tissue regeneration. This implies great promise for SA materials as a new implantable biomaterial for tissue regeneration.
家蚕丝素来源于驯化的家蚕（Bombyx mori），是一种具有低免疫原性、固有可生物降解性和可调节机械性能的蛋白质基生物聚合物，在生物医学应用中具有巨大的潜力。通过化学修饰来改变丝素蛋白的一级结构，可以扩展新的丝基生物材料的生成。受富含羧基的透明质酸的分子结构启发，报道了一种高效且具有扩大潜力的方法，可实现丝素蛋白的可控羧基化以制备丝酸（SA），并进一步研究了 SA 的生物学性质。SA 材料在不同的羧基化度（CD）下表现出可调的亲水性和酶降解性能。在小鼠体内皮下植入长达 1 个月的结果表明，具有高 CD 的 SA 材料表现出增强的降解，同时引起轻微的异物反应，包括低炎症反应和减少纤维囊包封。免疫荧光分析进一步表明，SA 材料具有促进血管生成的特性，并促进 M2 型巨噬细胞极化，从而促进组织再生。这意味着 SA 材料作为一种用于组织再生的新型可植入生物材料具有巨大的潜力。
