Kodama Koichi, Hasegawa Toya, Furukawa Yuri, Obata Masato, Ito Shohei, Hirose Takuji
Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama338-8570, Japan.
Langmuir. 2025 Jul 8;41(26):17269-17275. doi: 10.1021/acs.langmuir.5c02116. Epub 2025 Jun 26.
Amino acid-based low-molecular-weight gelators (LMWGs) attract considerable attention for the construction of supramolecular gels with controlled properties. Although most LMWGs behave as either organogelators or hydrogelators, several ambidextrous LMWGs have been reported. However, the factors determining this ambidextrous nature are unclear. Considering that structural differences between LMWGs affect their molecular assembly and gelation ability, analogues of chiral peptide-type amines were developed as LMWGs in this study to investigate the structural effects on their ambidextrous gelation properties. LMWGs with longer spacers behaved as only organogelators and lost their ambidextrous nature. Although the different structures of amide bonds (NHCO or CONH) decreased the ambidextrous nature, replacing one amide group with a urea moiety improved the ambidextrous gelation ability owing to the formation of stronger hydrogen bonds. The self-assembled structures of the gelators were examined, and the relationship between the structure and the gelation ability was elucidated. Finally, the application of the supramolecular gel derived from the LMWGs to the chiral recognition of a carboxylic acid was demonstrated.
基于氨基酸的低分子量凝胶剂(LMWGs)在构建具有可控性质的超分子凝胶方面引起了广泛关注。尽管大多数LMWGs要么表现为有机凝胶剂,要么表现为水凝胶剂,但已有报道称存在几种具有双重性质的LMWGs。然而,决定这种双重性质的因素尚不清楚。考虑到LMWGs之间的结构差异会影响其分子组装和凝胶化能力,本研究开发了手性肽型胺的类似物作为LMWGs,以研究结构对其双重凝胶化性质的影响。具有较长间隔基的LMWGs仅表现为有机凝胶剂,失去了其双重性质。尽管酰胺键(NHCO或CONH)的不同结构降低了双重性质,但用脲部分取代一个酰胺基团由于形成了更强的氢键而提高了双重凝胶化能力。研究了凝胶剂的自组装结构,并阐明了结构与凝胶化能力之间的关系。最后,展示了源自LMWGs的超分子凝胶在羧酸手性识别中的应用。