Microcalorimetric studies of the effects of MgCl2 concentrations and pH on the adsorption of DNA on montmorillonite, kaolinite and goethite
Microcalorimetric studies of the effects of MgCl2 concentrations and pH on the adsorption of DNA on montmorillonite, kaolinite and goethite
复制标题
DOI：
10.1016/j.clay.2005.11.004
复制
发表时间：
2006-04-01
影响因子：
5.6
通讯作者：
Zhang, XW
中科院分区：
文献类型：
--
作者：
Cai, P;Huang, QY;Zhang, XW
本研究试图了解不同环境条件下DNA与土壤中常见矿物蒙脱石、高岭石和针铁矿的相互作用机制。通过平衡吸附和直接测定吸附曲线，研究了MgCl_2浓度（0、1、10和60 mM）和pH（3.0、5.0、7.0和9.0）对DNA在供试矿物上吸附的影响。吸附等温线拟合的Langmuir模型表明，最大容量和亲和力的DNA吸附矿物MgCl 2浓度和pH值的降低而增加。没有DNA吸附在蒙脱石上pH值为9.0。在不同体系中，DNA的吸附量（Δ H-ads）为-0.3 ~4.9kJ·g（-1）。DNA在蒙脱石、高岭石和针铁矿上的吸附均为放热反应（-0.3
This study attempted to comprehend the interaction mechanisms between DNA and the common minerals in soil such as montmorillonite, kaolinite and goethite at various environmental conditions. The effects of MgCl2 concentrations (0, 1, 10 and 60 mM) and pH (3.0, 5.0, 7.0 and 9.0) on the adsorption of DNA on the examined minerals were investigated by the equilibrium adsorption and direct measurement of adsorption enthalpies. The adsorption isotherms fitted by the Langmuirian model revealed that the maximum capacities and affinities of DNA adsorption on minerals increased with MgCl2 concentrations and decrease of pH. No DNA was adsorbed on montmorillonite at pH 9.0. The values of DNA adsorption enthalpies (Delta H-ads) ranged from -0.3 to 4.9 kJ g(-1) at different systems. The Delta H-ads values decreased with increasing MgCl2 concentrations and decreasing pH. The adsorption of DNA on montmorillonite, kaolinite and goethite was an exothermic reaction (-0.3