title: Self-assembled chiral helical nanofibers by amphiphilic dipeptide derived from d- or l-threonine and application as a template for the synthesis of Au and Ag nanoparticles.
abstract: The discovery of a class of self-assembling peptides that spontaneously undergo self-organization into well-ordered structures opened a new avenue for molecular fabrication of biological materials. In this paper, the structure controlled helical nanofibers were prepared by two artificial β-sheet dipeptides with long alkyl chains derived from l- and d-threonine (Thr) and sodium hydroxide (NaOH). These helical nanofibers have been characterized using transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), circular dichroism (CD), Fourier transform infrared (FT-IR) spectroscopy, and X-ray powder diffraction (XRD). It was demonstrated that the helicity of the nanofibers could be easily controlled by changing the chirality of the constituent amino acids in the peptide species (d- or l-threonine). Moreover, the hydrogen bonding interactions between the amide groups as well as the hydrophobic interactions among the alkyl chains play important roles in the self-assembly process. It also can be observed that with the passage of time, the hydrogen bonding interactions between the individual nanofiber induced the conversion from nanofibers to nanobelts. Particularly, gold and silver nanoparticles performed good catalytic ability were synthesized using the assembled nanofibers as template.
authors: Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, Shanda Nanlu No. 27, Jinan 250100, PR China.
authors: Han
authors: H
authors: Zhang
authors: Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, Shanda Nanlu No. 27, Jinan 250100, PR China; National Engineering Technology Research Center for Colloidal Materials, Shandong University, Shanda Nanlu No. 27, Jinan 250100, PR China. Electronic address: xinx@sdu.edu.cn.
authors: Xia
authors: X
authors: Xin
authors: Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, Shanda Nanlu No. 27, Jinan 250100, PR China.
authors: Jichao
authors: J
authors: Sun
authors: Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, Shanda Nanlu No. 27, Jinan 250100, PR China.
authors: Liupeng
authors: L
authors: Zhao
authors: Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, Shanda Nanlu No. 27, Jinan 250100, PR China.
authors: Jinglin
authors: J
authors: Shen
authors: National Engineering Technology Research Center for Colloidal Materials, Shandong University, Shanda Nanlu No. 27, Jinan 250100, PR China.
authors: Zhaohua
authors: Z
authors: Song
authors: Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, Shanda Nanlu No. 27, Jinan 250100, PR China. Electronic address: shilingyuan@sdu.edu.cn.
authors: Shiling
authors: S
authors: Yuan
mesh_terms: D004151:Dipeptides / Q000138:chemical synthesis*; D006046:Gold / Q000737:chemistry; D006860:Hydrogen Bonding; D057927:Hydrophobic and Hydrophilic Interactions; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D057139:Nanofibers / Q000737:chemistry* / Q000648:ultrastructure; D000072757:Protein Conformation, beta-Strand; D012834:Silver / Q000737:chemistry; D012972:Sodium Hydroxide / Q000737:chemistry; D013237:Stereoisomerism; D013501:Surface-Active Agents; D013912:Threonine / Q000737:chemistry*
chemical_list: D004151:Dipeptides; D013501:Surface-Active Agents; D013912:Threonine; D012834:Silver; D012972:Sodium Hydroxide; D006046:Gold
keywords: Dipeptide; Helicity; Nanofibers; Nanoparticles; Threonine