Mantion Alexandre, Taubert Andreas
Department of Chemistry, Klingelbergstr. 80, University of Basel, CH-4056 Basel, Switzerland.
Macromol Biosci. 2007 Feb 12;7(2):208-17. doi: 10.1002/mabi.200600192.
L-Valine-based oligopeptides with the general structure Z-(L-Val)(n)-OMe or -OH (n = 1-4) form stable organogels in a variety of solvents, including the inorganic liquid tetraethylorthosilicate. The acid form Z-(L-Val)(n)-OH is a less efficient gelator than the methyl ester, but forms stable organogels in aromatic solvents and di- and trichloromethane. In all cases the peptides form micrometer long helical fibers with a beta-sheet structure. IR and X-ray diffraction show that the peptides have closely related structures in the crystalline state and the fibers in the organogels. The gels are efficient templates for the fabrication of complex titania architectures on a (sub)micron length scale: at low peptide concentrations titania spheres form and at higher concentrations one-dimensional shapes like hollow titania tubes or titania fibers are observed. The tubes are stable towards calcination whereas the fibers (partially) transform into spherical or even bulk particles.
具有通式Z-(L-缬氨酸)(n)-OMe或-OH（n = 1 - 4）的基于L-缬氨酸的寡肽在包括无机液体原硅酸四乙酯在内的多种溶剂中形成稳定的有机凝胶。酸形式的Z-(L-缬氨酸)(n)-OH作为凝胶剂的效率低于甲酯，但在芳香族溶剂以及二氯甲烷和三氯甲烷中能形成稳定的有机凝胶。在所有情况下，这些肽都会形成具有β-折叠结构的微米长螺旋纤维。红外光谱和X射线衍射表明，这些肽在晶体状态和有机凝胶中的纤维具有密切相关的结构。这些凝胶是在（亚）微米长度尺度上制备复杂二氧化钛结构的有效模板：在低肽浓度下形成二氧化钛球体，在较高浓度下观察到一维形状，如空心二氧化钛管或二氧化钛纤维。这些管对煅烧稳定，而纤维（部分）会转变成球形甚至块状颗粒。
