A self-assembled nanofiber catalyst for ester hydrolysis
A self-assembled nanofiber catalyst for ester hydrolysis
复制标题
DOI：
10.1021/ja075044n
复制
发表时间：
2007-10-10
影响因子：
15
通讯作者：
Stupp, Samuel I.
中科院分区：
文献类型：
--
作者：
Guler, Mustafa O.;Stupp, Samuel I.
基于超分子体系的催化粒子在催化领域取得了显著的进步。在这项工作中，合成了组氨酸功能化的自组装多肽两亲物(PAS)，以形成具有内部有序性的高长径比自组装纳米纤维，该纳米纤维可以提供能够进行酯水解咪唑基的基团。用透射电子显微镜和圆二色谱研究了催化粒子的分子自组装。利用组氨酸残基设计了催化2，4-二硝基苯乙酸酯(DNPA)水解的活性中心。通过UV-Vis光谱分析和Michaelis-Menten酶动力学模型研究了纳米纤维对DNPA的酶催化作用。与具有较少有序性的球形聚集体和单分子催化剂相比，自组装纳米纤维的存在显著加快了水解率。
Catalytic particles based on supramolecular systems have demonstrated significant improvement in the field of catalysis. In this work, histidine-functionalized self-assembling peptide amphiphiles; (PAs) were synthesized in order to form self-assembly high-aspect-ratio nanofibers with internal order that can present imidazolyl groups capable of ester hydrolysis. Self-assembly of the molecules making up the catalytic particle was studied by transmission electron microscopy and circular dichroism. The reactive sites were designed with histidine residues to catalyze the hydrolysis of 2,4-dinitrophenyl acetate (DNPA). Enzymatic hydrolysis of DNPA was observed in the presence of the nanofibers by UV-vis spectroscopy and the Michaelis-Menten enzyme kinetics model. Significantly faster hydrolysis rate was observed in the presence of self-assembled nanofibers relative to spherical aggregates expected to have less order as well as single molecule catalysts.