title: Thixotropic hydrogelators based on a cyclo(dipeptide) derivative.
abstract: Thixotropic hydrogelators have great potential in biomedical and biotechnological applications. In this study, we report new hydrogelators and their behavior during gel-sol-gel transitions. In particular, cyclo(L-O-hydroxyhexylaspartyl-L-phenylalanyl), which was synthesized with 1,6-hexanediol, formed a thermally/isothermally reversible physical gel with several solvents, including pure water, saline, alcohols, as well as 1.0 M aqueous NaCl, KCl, CaCl2, and MgCl2 solutions. TEM observations showed self-assembled fibers with diameters of 10-100 nm. FT-IR results revealed that the gels were mainly formed by hydrogen bonding and van der Waals forces; thixotropic behavior resulted from the disruption of the van der Waals forces between the alkylene chains under shearing. These results were repeatedly and reproducibly observed at room temperature, even when measurements were repeated many times.
authors.affiliation: Interdisciplinary Graduate School of Science and Technology and ‡Faculty of Textile Science and Technology, Shinshu University , 3-15-1 Tokida, Ueda-shi, Nagano 386-8567, Japan.
authors.forename: Hiroko
authors.initials: H
authors.lastname: Hoshizawa
authors.forename: Yuta
authors.initials: Y
authors.lastname: Minemura
authors.forename: Katsunori
authors.initials: K
authors.lastname: Yoshikawa
authors.forename: Masahiro
authors.initials: M
authors.lastname: Suzuki
authors.forename: Kenji
authors.initials: K
authors.lastname: Hanabusa
mesh_terms: D004151:Dipeptides / Q000737:chemistry*; D020100:Hydrogels / Q000138:chemical synthesis / Q000737:chemistry*; D006860:Hydrogen Bonding; D057927:Hydrophobic and Hydrophilic Interactions; D015394:Molecular Structure; D010316:Particle Size; D013499:Surface Properties
chemical_list: D004151:Dipeptides; D020100:Hydrogels