组氨酸插层锌铝水滑石的分子动力学模拟及其缓释历程  

Molecular Dynamics Simulation of Histidine Intercalated Zn/Al Hydrotalcite and Releasing Course

作　　者：李远[1] 倪哲明[1] 胥倩[1] 姚萍[1] 刘晓明[1] 王巧巧[1] 

机构地区：[1]浙江工业大学化学工程与材料学院,杭州310032

出　　处：《硅酸盐学报》2011年第1期63-68,共6页Journal of The Chinese Ceramic Society

基　　金：浙江省自然科学基金(Y406609)资助项目

摘　　要：通过构建组氨酸插层锌铝水滑石的周期性模型,利用分子动力学方法对体系的结构参数和水合过程进行模拟。结果表明:随着水含量的升高,层间距dc呈线性增加,当水含量Nw为2～3时,dc值与X射线衍射及元素分析结论相吻合,说明模拟过程对实际水合历程具有良好的预测性。进而由氢键模拟预测体系的水合历程:水分子首先衔接部分阴离子和层板,然后逐渐与层板形成更多的氢键而将阴离子和层板分隔,最后在层板与阴离子之间排布成层。水合能逐渐升高并最终趋于平衡,平衡值仍低于体相水的势能。利用模拟所得的水合性质解释了组氨酸缓释曲线的变化过程,组氨酸之所以释放缓慢且饱和释放值仅为60%,可能与体系较低的平衡水合能和自身的氢键形成规律及分子结构有关。A periodical model of histidine intercalated Zn–Al layered double hydroxides was proposed to simulate its structural prop-erty and hydrated process based on the molecular dynamics.The result of simulation shows that the interlayer spacing increases line-arly as water molecules add.When water content Nw = 2–3,the value of the interlayer spacing was similar to the analytical value of X-ray diffraction and element analysis.It was indicated that the hydration process could be simulated.For the simulation of H-bonds,the hydration of the system was carried out as follows： water molecules initially linked layers and anions,and then formed more H-bonds with layers and gradually separated anions with layers,finally,they formed a kind of ＂water layer＂ between layers and ani-ons.The hydration energy increased gradually and obtained a saturated value at the end.The saturated value was lower than the po-tential of bulk water.The change of releasing curve for histidine could be explained via the hydrated property from the simulation.The slowly released histidine and the saturated releasing content of 60% could be related to the low saturated value of hydration en-ergy or the H-bonding mechanism and the molecular structure.

关 键 词：锌铝水滑石 组氨酸 分子动力学模拟 水合过程 缓释 

分 类 号：O614[理学—无机化学]