Thermoresponsive PEG-Coated Nanotubes as Chiral Selectors of Amino Acids and Peptides
Thermoresponsive PEG-Coated Nanotubes as Chiral Selectors of Amino Acids and Peptides
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DOI：
10.1002/smll.201800030
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发表时间：
2018-04-12
期刊：
影响因子：
13.3
通讯作者：
Yui, Hiroharu
中科院分区：
文献类型：
--
作者：
Kameta, Naohiro;Dong, Jiuchao;Yui, Hiroharu
通过糖脂和聚乙二醇（PEG）衍生物的共组装过程制备了一系列在内表面具有致密短聚乙二醇链层的纳米管。通过加热使PEG链脱水，增加了纳米管通道的疏水性，荧光染料标记的氨基酸从本体溶液中被萃取出来。通过冷却使PEG链再水合，导致氨基酸反萃取回本体溶液中。由于纳米管的超分子手性，在反萃取过程中氨基酸对映体能够被分离，当氨基酸从纳米管中释放时，这种分离可以通过肉眼观察到荧光的变化来检测。通过调节纳米管通道的化学特性和内径，手性分离的效率和选择性得以提高。例如，与宽纳米管通道（8纳米）相比，窄纳米管通道（4纳米）为运输氨基酸提供了更有效的静电吸引和氢键相互作用环境。在纳米管内表面引入支链烷基链能够实现含疏水氨基酸的肽的手性分离。这里描述的体系在生物和医学领域提供了一种简单、快速且现场的手性分离方法。
A series of nanotubes with a dense layer of short poly(ethylene glycol) (PEG) chains on the inner surface are prepared by means of a coassembly process using glycolipids and PEG derivatives. Dehydration of the PEG chains by heating increases the hydrophobicity of the nanotube channel and fluorescent-dye-labeled amino acids are extracted from bulk solution. Rehydration of the PEG chains by cooling results in back-extraction of the amino acids into the bulk solution. Because of the supramolecular chirality of the nanotubes, amino acid enantiomers can be separated in the back-extraction procedure, which is detectable with the naked eye as a change in fluorescence as the amino acids are released from the nanotubes. The efficiency and selectivity of the chiral separation are enhanced by tuning the chemical features and inner diameter of the nanotube channels. For example, compared with wide nanotube channels (8 nm), narrow nanotube channels (4 nm) provide more effective electrostatic attraction and hydrogen bond interaction environments for the transporting amino acids. Introduction of branched alkyl chains to the inner surface of the nanotubes enables chiral separation of peptides containing hydrophobic amino acids. The system described here provides a simple, quick, and on-site chiral separation in biological and medical fields.