Department of Materials Science and Engineering, University of Delaware Newark, DE, USA.
Department of Materials Science and Engineering, University of Delaware Newark, DE, USA ; Biomedical Engineering, University of Delaware Newark, DE, USA ; Delaware Biotechnology Institute Newark, DE, USA.
Front Chem. 2014 Apr 28;2:21. doi: 10.3389/fchem.2014.00021. eCollection 2014.
The outstanding high-frequency properties of emerging resilin-like polypeptides (RLPs) have motivated their development for vocal fold tissue regeneration and other applications. Recombinant RLP hydrogels show efficient gelation, tunable mechanical properties, and display excellent extensibility, but little has been reported about their transient mechanical properties. In this manuscript, we describe the transient mechanical behavior of new RLP hydrogels investigated via both sinusoidal oscillatory shear deformation and uniaxial tensile testing. Oscillatory stress relaxation and creep experiments confirm that RLP-based hydrogels display significantly reduced stress relaxation and improved strain recovery compared to PEG-based control hydrogels. Uniaxial tensile testing confirms the negligible hysteresis, reversible elasticity and superior resilience (up to 98%) of hydrated RLP hydrogels, with Young's modulus values that compare favorably with those previously reported for resilin and that mimic the tensile properties of the vocal fold ligament at low strain (<15%). These studies expand our understanding of the properties of these RLP materials under a variety of conditions, and confirm the unique applicability, for mechanically demanding tissue engineering applications, of a range of RLP hydrogels.
新兴的类弹性蛋白多肽（RLP）具有出色的高频特性，这促使它们被开发用于声带组织再生和其他应用。重组 RLP 水凝胶具有高效的凝胶化、可调的机械性能和优异的拉伸性，但关于其瞬态机械性能的报道很少。在本文中，我们通过正弦振荡剪切变形和单轴拉伸测试描述了新的 RLP 水凝胶的瞬态机械行为。振荡应力松弛和蠕变实验证实，与基于 PEG 的对照水凝胶相比，基于 RLP 的水凝胶的应力松弛显著降低，应变恢复得到改善。单轴拉伸测试证实了水合 RLP 水凝胶具有可忽略的滞后、可逆弹性和优异的弹性（高达 98%），杨氏模量值与先前报道的弹性蛋白相当，并模仿声带韧带在低应变（<15%）下的拉伸特性。这些研究扩展了我们对这些 RLP 材料在各种条件下的性能的理解，并证实了一系列 RLP 水凝胶在机械要求高的组织工程应用中的独特适用性。
