Tulli Ludovico G, Wang Wenjie, Lindemann William R, Kuzmenko Ivan, Meier Wolfgang, Vaknin David, Shahgaldian Patrick
Institute of Chemistry and Bioanalytics, School of Life Science, University of Applied Sciences and Arts Northwestern Switzerland , Muttenz, Switzerland.
Langmuir. 2015 Mar 3;31(8):2351-9. doi: 10.1021/acs.langmuir.5b00262. Epub 2015 Feb 20.
The interactions of Langmuir monolayers produced through the self-assembly of an amphiphilic p-carboxycalix[4]arene (1) with a series of divalent, fourth-period transition metals, at the air-water interface, were investigated. Changes in the interfacial behavior of 1 in response to the presence of CuCl2, CoCl2, MnCl2, and NiCl2 were studied by means of Langmuir compression isotherms and Brewster angle microscopy (BAM). The measurements revealed that the self-assembly properties of 1 are significantly affected by Cu(2+) ions. The interactions of 1-based monolayers with Co(2+) and Cu(2+) ions were further investigated by means of synchrotron radiation-based X-ray reflectivity (XRR), X-ray near-total-reflection fluorescence (XNTRF), and grazing incidence X-ray diffraction (GIXD). XNTRF and XRR analyses revealed that the monolayer of 1 binds more strongly to Cu(2+) than Co(2+) ions. In the presence of relatively high concentrations of Cu(2+) ions in the subphase (1.4 × 10(-3) M), XNTRF exhibited anomalous depth profile behavior and GIXD measurements showed considerably strong diffuse scattering. Both measurements suggest the formation of Cu(2+) clusters contiguous to the monolayer of 1.
研究了两亲性对羧基杯[4]芳烃（1）在空气-水界面自组装形成的朗缪尔单分子层与一系列二价第四周期过渡金属之间的相互作用。通过朗缪尔压缩等温线和布鲁斯特角显微镜（BAM）研究了1在CuCl2、CoCl2、MnCl2和NiCl2存在下界面行为的变化。测量结果表明，1的自组装性质受到Cu(2+)离子的显著影响。通过基于同步辐射的X射线反射率（XRR）、X射线近全反射荧光（XNTRF）和掠入射X射线衍射（GIXD）进一步研究了基于1的单分子层与Co(2+)和Cu(2+)离子的相互作用。XNTRF和XRR分析表明，1的单分子层与Cu(2+)的结合比与Co(2+)离子更强。在亚相中存在相对高浓度的Cu(2+)离子（1.4×10(-3) M）时，XNTRF表现出异常的深度分布行为，GIXD测量显示出相当强的漫散射。这两种测量结果都表明在与1的单分子层相邻处形成了Cu(2+)簇。
