作者:Andrew R. Hirst、Sangita Roy、Meenakshi Arora、Apurba K. Das、Nigel Hodson、Paul Murray、Stephen Marshall、Nadeem Javid、Jan Sefcik、Job Boekhoven、Jan H. van Esch、Stefano Santabarbara、Neil T. Hunt、Rein V. Ulijn
DOI:10.1038/nchem.861
日期:2010.12
Supramolecular gels, which demonstrate tunable functionalities, have attracted much interest in a range of areas, including healthcare, environmental protection and energy-related technologies. Preparing these materials in a reliable manner is challenging, with an increased level of kinetic defects observed at higher self-assembly rates. Here, by combining biocatalysis and molecular self-assembly, we have shown the ability to more quickly access higher-ordered structures. By simply increasing enzyme concentration, supramolecular order expressed at molecular, nano- and micro-levels is dramatically enhanced, and, importantly, the gelator concentrations remain identical. Amphiphile molecules were prepared by attaching an aromatic moiety to a dipeptide backbone capped with a methyl ester. Their self-assembly was induced by an enzyme that hydrolysed the ester. Different enzyme concentrations altered the catalytic activity and size of the enzyme clusters, affecting their mobility. This allowed structurally diverse materials that represent local minima in the free energy landscape to be accessed based on a single gelator structure. Supramolecular gels show promise in diverse areas, including healthcare and energy technologies, owing to tunable properties that arise directly from the organization of their building blocks. Researchers have now been able to control this behaviour by combining enzymatic catalysis with molecular self-assembly. Although it seems counter-intuitive, gels that assembled faster showed fewer defects.
超分子凝胶具有可调功能,在医疗保健、环境保护和能源相关技术等多个领域备受关注。以可靠的方式制备这些材料具有挑战性,因为在较高的自组装速率下会观察到更多的动力学缺陷。在这里,通过将生物催化与分子自组装相结合,我们展示了更快获得更高有序结构的能力。只需增加酶的浓度,分子、纳米和微米级的超分子有序性就会显著增强,重要的是,凝胶剂的浓度保持不变。双亲分子的制备方法是在二肽骨架上连接一个芳香分子,并以甲酯封顶。它们的自组装是由一种水解酯的酶诱导的。不同浓度的酶会改变酶簇的催化活性和大小,从而影响其流动性。这样,就可以根据单一凝胶体结构获得结构多样的材料,这些材料代表了自由能图谱中的局部最小值。超分子凝胶在医疗保健和能源技术等多个领域都大有可为,因为其可调特性直接来源于其构建模块的组织。现在,研究人员已经能够通过将酶催化与分子自组装相结合来控制这种行为。虽然这似乎有违直觉,但组装速度更快的凝胶显示出更少的缺陷。