Supramolecular hydrogels attract extensive attention as waterborne biocompatible materials like biological tissues. Here we developed poly[N-(2-acetamidoethyl)acrylamide] (PAAE) supramolecular hydrogels with multiple hydrogen bonds, which exhibit ideal mechanical performances, such as strong resistance to compression and stretch, high stability in acidic or high ionic strength solution, excellent waterborne adhesiveness, self-healing and swelling behaviors. The small molecular precursor for PAAE hydrogels possesses great solubility up to 70 wt% in deionized water and superior infiltration capability to mouse brain tissues at 5 °C, and can be in situ polymerized at 30–45 °C and swollen in deionized water with a 1.75 times linear expansion factor. There is no noticeable loss of fluorescence intensity during the whole process from small molecular infiltration and polymerization to expansion. The mouse brain slices were embedded and used for expansion microscopy with enhanced optical resolution and preserved structure integrity.

中文翻译：

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具有多个H键交联的聚[N-（2-乙酰氨基乙基）丙烯酰胺]超分子水凝胶可实现小鼠脑嵌入和扩展显微镜

超分子水凝胶作为水性生物相容性材料（如生物组织）引起了广泛关注。在这里，我们开发了具有多个氢键的聚[ N-（2-乙酰氨基乙基）丙烯酰胺]（PAAE）超分子水凝胶，它们具有理想的机械性能，例如强的抗压缩和拉伸性，在酸性或高离子强度溶液中的高稳定性，优异的水性粘合性，自我修复和膨胀行为。PAAE水凝胶的小分子前体在去离子水中的溶解度高达70 wt％，并且在5°C下对小鼠脑组织具有优异的渗透能力，并且可以原位在30–45°C下聚合，并在去离子水中膨胀，其线性膨胀系数为1.75倍。从小分子渗透和聚合到膨胀，整个过程没有明显的荧光强度损失。嵌入小鼠脑切片，并用于扩展显微镜，具有增强的光学分辨率和保留的结构完整性。