Molecular, Macromolecular Chemistry, and Materials, ESPCI Paris, CNRS, PSL University, 10 rue Vauquelin, 75005, Paris, France.
Université Grenoble Alpes, CNRS, CERMAV, 38000 Grenoble, France.
Soft Matter. 2024 Jul 3;20(26):5122-5133. doi: 10.1039/d4sm00287c.
Solid particles placed at the interface between hydrogels and biological tissues can create an adhesive joint through the adsorption of macromolecules onto their surfaces. Here, we investigated how this adhesion by particle bridging depends on the wetting of tissue surfaces and on the heterogeneities in tissue composition. peeling experiments were performed using poly(ethylene glycol) films coated with aggregates of silica nanoparticles deposited on the internal tissues of porcine liver. We show that the adhesion produced by particle bridging is altered by the presence of fluid wetting the tissue-hydrogel interface. For both uncoated and coated films, a transition from lubricated to adhesive contact was observed when all the interfacial fluid was drained. The presence of a silica nanoparticle coating shifted the transition towards more hydrated conditions and significantly enhanced adhesion in the adhesive regime. After 5 min of contact, the adhesion energy achieved on liver parenchyma with the coated films (7.7 ± 1.9 J m) was more than twice that of the uncoated films (3.2 ± 0.3 J m) or with a surgical cyanoacrylate glue (2.9 ± 1.9 J m). Microscopic observations during and after peeling revealed different detachment processes through either particle detachment or cohesive fracture in the tissue. These mechanisms could be directly related to the microanatomy of the liver parenchyma. The effects of both interfacial wetting and tissue composition on adhesion may provide guidelines to tailor the design of tissue adhesives using particle bridging.
固体颗粒置于水凝胶和生物组织之间的界面上，可以通过大分子吸附到其表面来形成黏合接头。在这里，我们研究了颗粒桥接的这种粘附作用如何取决于组织表面的润湿性以及组织成分的不均匀性。使用涂有二氧化硅纳米颗粒聚集体的聚乙二醇薄膜进行了剥离实验，这些聚集体沉积在猪肝的内部组织上。我们表明，颗粒桥接产生的粘附作用会因润湿组织-水凝胶界面的流体的存在而改变。对于未涂层和涂层的薄膜，当所有界面流体都被排出时，观察到从润滑接触到黏附接触的转变。二氧化硅纳米颗粒涂层的存在将转变推向更水合的条件，并在黏附区域显著增强粘附力。在接触 5 分钟后，涂覆薄膜在肝实质上获得的粘附能（7.7 ± 1.9 J m）是未涂覆薄膜（3.2 ± 0.3 J m）或手术氰基丙烯酸酯胶（2.9 ± 1.9 J m）的两倍多。在剥离过程中和剥离后进行的微观观察揭示了通过颗粒脱离或组织内的内聚性断裂的不同的脱离过程。这些机制可能与肝实质的微观解剖结构直接相关。界面润湿性和组织成分对粘附的影响可以为使用颗粒桥接来定制组织粘合剂的设计提供指导。
