原文献：

Swelling-strengthening hydrogels by embedding with deformable nanobarriers

文献链接：

https://xueshu.baidu.com/usercenter/paper/show?paperid=1s4700n0ny460pa00t120v70tu715564&site=xueshu_se&hitarticle=1

作者：

Feng Wu1, Yan Pang & Jinyao Liu

原文摘要：

Biological tissues, such as muscle, can increase their mechanical strength after swelling dueto the existence of many biological membrane barriers that can regulate the transmembranetransport of water molecules and ions. Oppositely, typical synthetic materials show aswelling-weakening behavior, which always suffers from a sharp decline in mechanicalstrength after swelling, because of the dilution of the network. Here, we describe a swelling-strengthening phenomenon of polymer materials achieved by a bioinspired strategy. Lipo-somal membrane nanobarriers are covalently embedded in a crosslinked network to regulatetransmembrane transport. After swelling, the stretched network deforms the liposomes andsubsequently initiates the transmembrane diffusion of the encapsulated molecules that cantrigger the formation of a new network from the preloaded precursor. Thanks to the toughnature of the double-network structure, the swelling-strengthening phenomenon is achievedto polymer hydrogels successfully. Swelling-triggered self-strengthening enables the development of various dynamic materials.

脂质体膜纳米载体共价嵌入在一个交联网络中，以调节跨膜转运。膨胀后，拉伸的网络使脂质体变形，随后启动被包裹分子的跨膜扩散，从而触发预加载的前体形成一个新的网络。由于双网络结构的坚固性，聚合物成功地对水凝胶实现了膨胀强化现象。DBCO酸在其合成过程中与四聚乙二醇-胺的一步酰胺化反应合成了预载前体四-peg-DBCO。

选择水溶性N3-PEG3-N3和Tetra-PEG-DBCO作为可点击交联剂和第二网络的前体。将氢化大豆磷脂与胆固醇和二硬脂酰磷酸乙醇胺-peg2000-丙烯酰胺共组装制备了双键修饰的脂质体，而DBCO酸与Tetra-PEG-DBCO胺化合成。装载N3-PEG3-N3的修饰脂质体通过丙烯酰胺和N，N‘-亚甲基双丙烯酰胺的水自由基共聚反应共价连接到第一个网络。SSHs是通过在聚丙烯酰胺（PAM）水凝胶中预加载四PEG-DBCO凝胶获得的。

图：DBCO

通过DBCO酸与Tetra-PEG-DBCO的一步酰胺化反应合成了预载前Tetra-PEG-DBCO。将DBCO、HATU和无水DMF加入干瓶中，在搅拌下得到浅黄色溶液。然后将四聚胺加入无水DMF中。加入无水DIEA后，将反应混合物搅拌。然后，将混合物滴加入冷Et2O中，搅拌，得到白色固体粉末。再洗涤真空干燥，得到淡黄色粉末。用质子核磁共振光谱确定了所得化合物的结构。

结论：用质子核磁共振（1H NMR）光谱（Bruker Avance 500光谱仪）确定了DBCO酸与Tetra-PEG-DBCO的一步酰胺化反应合成了预载前体Tetra-PEG-DBCO的结构。