School of Chemistry and Materials Science, Ludong University, Yantai 264025, China.
Shandong Laboratory of Advanced Materials and Green Manufacturing at Yantai, Yantai 264000, China.
Langmuir. 2023 Nov 28;39(47):16750-16759. doi: 10.1021/acs.langmuir.3c01906. Epub 2023 Nov 14.
Low-molecular-weight peptide hydrogels can be formed by self-assembly through weak interactions, but the application of the hydrogel is influenced by its weak mechanical properties. Therefore, it is important to construct low-molecular-weight peptide hydrogels with excellent mechanical properties. In this work, we designed the pentapeptide molecule Fmoc-FFCKK-OH (abbreviated as FFCKK) with a sulfhydryl group, and another low-molecular-weight cross-linker ,-methylenebis(acrylamide) (MBA) was introduced to construct a hydrogel with excellent mechanical properties. The secondary structure change process of FFCKK and the assembly mechanism of hydrogel were analyzed using theoretical calculations and experimental characterizations. The occurrence of thiol-ene click chemistry provides covalent interaction in the hydrogel, and the synergistic effect ofcovalent interaction and hydrogen bonding improves the mechanical properties of the hydrogel by nearly 10-fold. The hydrogel was observed to be able to withstand a stress of 368 Pa and to break in a layer-by-layer manner by compression testing. The micromechanics of the hydrogels were characterized, and the excellent mechanical properties of the hydrogels were confirmed. The synergistic approach provides a new idea for the preparation of low-molecular-weight peptide hydrogels and facilitates the expansion of their potential applications in biomedical fields.
低分子质量肽水凝胶可以通过弱相互作用自组装形成，但水凝胶的应用受到其弱机械性能的影响。因此，构建具有优异机械性能的低分子质量肽水凝胶非常重要。在这项工作中，我们设计了带有巯基的五肽分子 Fmoc-FFCKK-OH（简称 FFCKK），并引入了另一个低分子质量交联剂 -，-亚甲基双（丙烯酰胺）（MBA），以构建具有优异机械性能的水凝胶。使用理论计算和实验表征分析了 FFCKK 的二级结构变化过程和水凝胶的组装机制。硫醇-烯点击化学反应的发生为水凝胶提供了共价相互作用，共价相互作用和氢键的协同效应使水凝胶的机械性能提高了近 10 倍。通过压缩测试观察到水凝胶能够承受 368 Pa 的应力，并以逐层的方式断裂。对水凝胶的微力学进行了表征，证实了水凝胶具有优异的机械性能。协同方法为低分子质量肽水凝胶的制备提供了新的思路，有助于扩大其在生物医学领域的潜在应用。
