Key Laboratory for Soft Chemistry and Functional Materials of Ministry of Education, School of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
Colloids Surf B Biointerfaces. 2013 Feb 1;102:398-404. doi: 10.1016/j.colsurfb.2012.07.029. Epub 2012 Jul 31.
In this study, the adsorption behaviors of nicotinamide adenine dinucleotide (NAD(+)) on nano-boehmite (γ-AlOOH) and nano-corundum (γ-Al(2)O(3)) surfaces were investigated. The results showed that NAD(+) was predominantly adsorbed at the boehmite/water and corundum/water interfaces in outer-sphere fashions by electrostatic interaction between NAD(+) phosphate and surface hydroxyl groups. However, the features of ATR-FTIR spectra suggested that some minor inner-sphere complex should be considered at low pH conditions on corundum surface, which was consistent with the effect of NAD(+) on dissolution rate of corundum. In addition, the adsorption data well fitted with Langmuir and Freundlich isotherms on the boehmite and corundum surfaces, respectively. Also, the Gibbs adsorption energy was negative on the boehmite surface, which indicated that the adsorption behavior was spontaneous.
在这项研究中，研究了烟酰胺腺嘌呤二核苷酸（NAD(+)）在纳米氧化铝（γ-AlOOH）和纳米刚玉（γ-Al(2)O(3))表面的吸附行为。结果表明，NAD(+)主要通过 NAD(+)磷酸盐和表面羟基之间的静电相互作用，以外层络合的形式吸附在水合氧化铝/水和水合刚玉/水界面上。然而，ATR-FTIR 光谱的特征表明，在低 pH 值条件下，刚玉表面可能存在一些较小的内层络合物，这与 NAD(+)对刚玉溶解速率的影响是一致的。此外，吸附数据分别在氧化铝和刚玉表面上很好地符合朗缪尔和弗伦德利希等温线。此外，在氧化铝表面上，吉布斯吸附能为负值，这表明吸附行为是自发的。
