State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry , Jilin University , Qianjin Avenue 2699 , Changchun 130012 , China.
Langmuir. 2019 Apr 9;35(14):4995-5003. doi: 10.1021/acs.langmuir.9b00273. Epub 2019 Apr 1.
The fabrication of peptide assemblies to mimic the functions of natural proteins represents an intriguing aim in the fields of soft materials. Herein, we present a kind of novel peptide-based adhesive coacervate for the exploration of the environment-responsive underwater adhesion. Adhesive coacervates are designed and synthesized by self-assembled condensation of a tripeptide and polyoxometalates in aqueous solution. Rheological measurements demonstrate that the adhesive coacervates exhibit shear thinning behavior, which allows them to be conveniently delivered for interfacial spreading through a narrow gauge syringe without high pressure. The complex coacervates are susceptible to pH and metal ions, resulting in the occurrence of a phase transition from the fluid phase to the gel state. Scanning electron microscopy demonstrates that the microscale structures of the gel-like phases are composed of interconnected three-dimensional porous networks. The rheological study reveals that the gel-like assemblies exhibited mechanical stiffness and self-healing properties. Interestingly, the gel-like samples show the capacity to adhere to various wet solid substrates under the waterline. The adhesion strength of the peptide-based gel is quantified by lap shear mechanical analysis. The fluid coacervate is further exploited in the preparation of "on-site" injectable underwater adhesives triggered by environmental factors. This finding is exciting and serves to expand our capability for the fabrication of peptide-based underwater adhesives in a controllable way.
制备模拟天然蛋白质功能的肽组装体是软物质领域中一个有趣的目标。在此，我们提出了一种新型的基于肽的水响应性水下附着用粘性凝聚体。粘性凝聚体是通过三肽和多金属氧酸盐在水溶液中的自组装缩合设计和合成的。流变学测量表明，粘性凝聚体表现出剪切变稀行为，这使得它们可以通过狭窄的注射器方便地输送到界面上，而无需高压。复合凝聚体对 pH 值和金属离子敏感，导致从流体相到凝胶相的相变发生。扫描电子显微镜表明，凝胶状相的微尺度结构由相互连接的三维多孔网络组成。流变学研究表明，凝胶状组装体表现出机械刚性和自修复性能。有趣的是，凝胶状样品在水线以下能够粘附到各种湿固底物上。通过搭接剪切机械分析对基于肽的凝胶的粘附强度进行定量。进一步利用流体凝聚体在环境因素触发下制备“就地”可注射水下胶粘剂。这一发现令人兴奋，为我们以可控的方式制备基于肽的水下胶粘剂的能力提供了扩展。
