Institute of Biomedical & Health Engineering, Shenzhen Institute of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen 518035, China.
Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences, Beijing 100083, China.
ACS Appl Mater Interfaces. 2022 Sep 21;14(37):42420-42429. doi: 10.1021/acsami.2c10117. Epub 2022 Sep 9.
Reliable functions of medical implants highly depend on biocompatible, conformal, and stable biointerfaces for seamless biointegration with biological tissues. Though flexible biointerfaces based on synthetic hydrogels have shown promise in optimizing implant biointegration via surgical suturing, physical attachment, or manual preshaping, they still suffer from poor adaptability, such as tissue damage by surgical suturing, low bioactivity, and difficulties in conformal contact and stable fixation, especially for specific tissues of large surface curvatures. Here, we report a bilayer hydrogel-based adaptive biointerface (HAB) made of two polysaccharide derivates, -hydroxysuccinimide (NHS) ester-activated alginate and chitosan, harnessing dual advantages of their different swelling and active groups. Leveraging on the differential swelling between the two hydrogel layers and covalent linkages with active groups at hydrogel interfaces, HABs can be programmed into sealed tubes with tunable diameters via water-induced compliable shape morphing and instant interfacial adhesion. We further demonstrate that the polysaccharide-based morphing-to-adhesion HAB possesses outstanding bioactivity in directing cellular focal adhesion and intercellular junction, versatile geometrical adaptability to diverse tubular tissues with a wide range of surface curvatures (2.8 × 10-1.3 × 10 m), and excellent mechanical stability in high load-/shear-bearing physiological environments (blood flow volume: 85 mm·s). HABs overcome the limitations of existing biointerfaces in terms of poor bioactivity and difficult biointegration with biological tissues of large surface curvatures, holding promise to open new avenues for adaptive biointerfaces and reliable medical implants.
医疗植入物的可靠功能高度依赖于生物相容性、顺应性和稳定的生物界面，以实现与生物组织的无缝生物整合。尽管基于合成水凝胶的柔性生物界面通过手术缝合、物理附着或手动预成型在优化植入物生物整合方面显示出了前景，但它们仍然存在适应性差的问题，例如手术缝合造成的组织损伤、生物活性低以及难以顺应接触和稳定固定，特别是对于具有大表面曲率的特定组织。在这里，我们报告了一种由两种多糖衍生物组成的双层水凝胶基自适应生物界面（HAB），-羟基琥珀酰亚胺（NHS）酯活化的海藻酸盐和壳聚糖，利用它们不同的溶胀和活性基团的双重优势。利用两层水凝胶之间的溶胀差异以及水凝胶界面处的活性基团的共价键合，HAB 可以通过水诱导的顺应性形状变形和瞬间界面粘附编程成具有可调直径的密封管。我们进一步证明，基于多糖的变形-粘附 HAB 在指导细胞焦点粘附和细胞间连接方面具有出色的生物活性，具有多种几何适应性，能够适应各种表面曲率范围广泛的管状组织（2.8×10-1.3×10 m），并且在高负载/剪切承载生理环境中具有出色的机械稳定性（血流体积：85 mm·s）。HAB 克服了现有生物界面在生物活性差和难以与大表面曲率的生物组织整合方面的局限性，为自适应生物界面和可靠的医疗植入物开辟了新的途径。
