Yang Zhimou, Liang Gaolin, Wang Ling, Xu Bing
Department of Chemistry and Bioengineering Program, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
J Am Chem Soc. 2006 Mar 8;128(9):3038-43. doi: 10.1021/ja057412y.
We have designed and synthesized a new hydrogelator Nap-FFGEY (1), which forms a supramolecular hydrogel. A kinase/phosphatase switch is used to control the phosphorylation and dephosphorylation of the hydrogelator and to regulate the formation of supramolecular hydrogels. Adding a kinase to the hydrogel induces a gel-sol phase transition in the presence of adenosine triphosphates (ATP) because the tyrosine residue is converted into tyrosine phosphate by the kinase to give a more hydrophilic molecule of Nap-FFGEY-P(O)(OH)(2) (2); treating the resulting solution with a phosphatase transforms 2 back to 1 and restores the hydrogel. Electron micrographs of the hydrogels indicate that 1 self-assembles into nanofibers. Subcutaneous injection of 2 in mice shows that 80.5 +/- 1.2% of 2 turns into 1 and results in the formation of the supramolecular hydrogel of 1 in vivo. This simple biomimetic approach for regulating the states of supramolecular hydrogels promises a new way to design and construct biomaterials.
我们设计并合成了一种新型水凝胶剂Nap-FFGEY（1），它能形成超分子水凝胶。利用激酶/磷酸酶开关来控制水凝胶剂的磷酸化和去磷酸化，并调节超分子水凝胶的形成。在水凝胶中加入激酶，在三磷酸腺苷（ATP）存在的情况下会引发凝胶-溶胶相转变，因为酪氨酸残基会被激酶转化为磷酸酪氨酸，从而得到一个更具亲水性的Nap-FFGEY-P(O)(OH)(2)分子（2）；用磷酸酶处理所得溶液会将2转化回1并恢复水凝胶状态。水凝胶的电子显微镜图像表明1会自组装成纳米纤维。在小鼠皮下注射2的结果显示，80.5±1.2%的2会转化为1，并在体内形成1的超分子水凝胶。这种调节超分子水凝胶状态的简单仿生方法有望为生物材料的设计和构建提供一种新途径。
