Advanced Science Research Center, Graduate Center, City University of New York, New York, NY, USA.
Department of Chemical Engineering and Materials Science, University of California, Irvine, Irvine, CA, USA.
Nat Chem. 2018 Jul;10(7):696-703. doi: 10.1038/s41557-018-0047-2. Epub 2018 Apr 30.
Aqueous compatible supramolecular materials hold promise for applications in environmental remediation, energy harvesting and biomedicine. One remaining challenge is to actively select a target structure from a multitude of possible options, in response to chemical signals, while maintaining constant, physiological conditions. Here, we demonstrate the use of amino acids to actively decorate a self-assembling core molecule in situ, thereby controlling its amphiphilicity and consequent mode of assembly. The core molecule is the organic semiconductor naphthalene diimide, functionalized with D- and L- tyrosine methyl esters as competing reactive sites. In the presence of α-chymotrypsin and a selected encoding amino acid, kinetic competition between ester hydrolysis and amidation results in covalent or non-covalent amino acid incorporation, and variable supramolecular self-assembly pathways. Taking advantage of the semiconducting nature of the naphthalene diimide core, electronic wires could be formed and subsequently degraded, giving rise to temporally regulated electro-conductivity.
水相兼容的超分子材料在环境修复、能源收集和生物医学等领域有应用前景。目前仍面临的一个挑战是,在保持生理条件不变的情况下,根据化学信号主动从众多可能的选择中选择目标结构。在这里,我们展示了使用氨基酸在原位主动修饰自组装核心分子,从而控制其两亲性和随后的组装方式。核心分子是有机半导体萘二酰亚胺,用 D-和 L-酪氨酸甲酯作为竞争反应位点进行功能化。在α-糜蛋白酶和选定的编码氨基酸存在的情况下,酯水解和酰胺化之间的动力学竞争导致共价或非共价氨基酸掺入以及可变的超分子自组装途径。利用萘二酰亚胺核心的半导体性质,可以形成电子线,随后进行降解,从而产生时间调节的导电性。