Self-assembling peptides: a combined XPS and NEXAFS investigation on the structure of two dipeptides Ala-Glu, Ala-Lys
Self-assembling peptides: a combined XPS and NEXAFS investigation on the structure of two dipeptides Ala-Glu, Ala-Lys
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DOI：
10.1016/j.msec.2007.02.004
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发表时间：
2008-03
期刊：
影响因子：
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通讯作者：
G. Polzonetti;C. Battocchio;M. Dettin;Roberta Gambaretto;C. Bello;Vincenzo Carravetta;S. Monti;G. Iucci
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文献类型：
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作者：
G. Polzonetti;C. Battocchio;M. Dettin;Roberta Gambaretto;C. Bello;Vincenzo Carravetta;S. Monti;G. Iucci
用X射线光电子能谱（XPS）和近边X射线吸收精细结构谱（NEXAFS）研究了16单元自互补两亲性寡肽EAK 16的两个二肽AE（Lalanine-L-glutamic acid）和AK（Lalanine-L-lysine）。两种二肽在TiO 2上的薄膜，一种杰出的生物相容性表面，通过从水溶液中孵育来制备。还研究了惰性Au衬底上的二肽厚膜以进行比较。用XPS研究了样品的化学结构和组成，用NEXAFS方法研究了二肽在TiO 2表面的C-K边和N-K边的取向。为了产生一些见解的吸附几何形状和分子取向的MD（分子动力学）模拟也进行了。AE和AK的分子和电子表征为解释更复杂的肽谱提供了一个很好的模型。
The two dipeptides AE (Lalanine–Lglutamic acid) and AK (Lalanine–Llysine), that constitute the “building blocks” of the 16-unit self-complementary amphiphilic oligopeptide EAK16, have been investigated by XPS (X-ray photoelectron spectroscopy) and NEXAFS (near-edge X-ray absorption fine structure) spectroscopy. Thin films of both dipeptides on TiO2, a distinguished biocompatible surface, were prepared by incubation from aqueous solutions. Thick films of dipeptides on inert Au substrates were also studied for comparison. The chemical structure and composition were investigated by XPS spectroscopy; furthermore, molecular orientation of dipeptides on TiO2was checked by angular dependent NEXAFS measurements at both C–K and N–K edges. In order to yield some insight on adsorption geometry and molecular orientation MD (molecular dynamic) simulations were also carried out. The performed molecular and electronic characterization of AE and AK provides an excellent model for the interpretation of more complex peptide spectra.