Over the last few years, hydrogels have been proposed for many biomedical applications, including drug delivery systems and scaffolds for tissue engineering. In particular, peptides have been envisioned as excellent candidates for the development of hydrogel materials, due to their intrinsic biocompatibility, ease of handling, and intrinsic biodegradability. Recently, we developed a novel hybrid polymer–peptide conjugate, PEG₈-(FY)3, which is able to self-assemble into a self-supporting soft hydrogel over dry and wet surfaces as demonstrated by molecular dynamics simulation. Here, we describe the synthesis and supramolecular organization of six novel hexapeptides rationally designed by punctual chemical modification of the primary peptide sequence of the ancestor peptide (FY)3. Non-coded amino acids were incorporated by replacing the phenylalanine residue with naphthylalanine (Nal) and tyrosine with dopamine (Dopa). We also studied the effect of the modification of the side chain and the corresponding PEGylated peptide analogues, on the structural and mechanical properties of the hydrogel. Secondary structure, morphology and rheological properties of all the peptide-based materials were assessed by various biophysical tools. The in vitro biocompatibility of the supramolecular nanostructures was also evaluated on fibroblast cell lines. We conclude that the PEG₈-(Nal-Dopa)3 hydrogel possesses the right properties to serve as a scaffold and support cell growth.

中文翻译：

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基于双功能肽的3D水凝胶支架。

在过去的几年中，已经提出将水凝胶用于许多生物医学应用，包括药物递送系统和用于组织工程的支架。特别地，由于其固有的生物相容性，易处理性和固有的生物降解性，已将肽设想为开发水凝胶材料的极佳候选者。最近，我们开发了一种新型的杂化聚合物-肽共轭物PEG ₈-（FY）3，它能够在干燥和潮湿的表面上自组装成自支撑的软水凝胶，如分子动力学模拟所示。在这里，我们描述了六种新颖的六肽的合成和超分子组织，这些六肽是通过对祖先肽（FY）3的一级肽序列进行点化学修饰而合理设计的。通过用萘丙氨酸（Nal）取代苯丙氨酸残基和用多巴胺（Dopa）取代酪氨酸来掺入非编码氨基酸。我们还研究了侧链修饰和相应的PEG化肽类似物对水凝胶的结构和机械性能的影响。通过各种生物物理工具评估了所有基于肽的材料的二级结构，形态和流变特性。在体外在成纤维细胞系上还评估了超分子纳米结构的生物相容性。我们得出的结论是，PEG _8-（Nal-Dopa）3水凝胶具有正确的特性，可以用作支架并支持细胞生长。