摘要
采用UV-vis光谱法,在pH=7.00环境中用摩尔比法确定了鲱鱼精DNA与镱(Yb)的结合比nDNA:nYb=1:3,表观摩尔吸光系数ε=7.52×103L.mol-1.cm-1,聚乙烯吡咯烷酮(PVP)与鲱鱼精DNA-镱(Ⅲ)配合物(DNA(Yb)3)的结合比nPVP:nDNA(Yb)3=4:1,表观摩尔吸光系数ε=2.68×105L.mol-1.cm-1。用双倒数法求得结合常数K1θ2℃=0.965×102L.mol-1和K2θ2℃=0.218×102L.mol-1,△rHmθ,22℃=-1.04×105J.mol-1,△rSmθ,22℃=-3.27×102J.mol-1.K-1,△rGmθ,22℃=-0.76×104J.mol-1,该过程为焓驱动。确定了PVP-Yb(Ⅲ)与hsDNA之间为沟区作用方式。
With the methods of UV-vis spectra in physiological pH environment （ pH = 7.00）, the binding ratio of n DNA ： n Yb = 1 ： 3, n eve ： n DNA（Yb）3 = 4 ： 1 and the molar absorptivity of ε DNA-Yb = 7.52×10^3L·mol^-1·cm^-1, ε PVP-DSA（Yb） 3 =2.68×10^5·mol^-1·cm^-1were confirmed by molar ratio method. The binding constant ofK^θ12℃=0.965×10^2L·mol^-1 =0.218×10^2L·mol^-1 were confirmed by double reciprocal method. Thermodynamic parameters were calculated including changes in enthalpy （ △rH^θm,22℃） entropy （ △rS^θm22℃ ） and Gibbs free energy （ where the values were - 1.04×10^5J·mol^-1, -3.27×10^2J·mol^-1·K^-1and -0.76×10^4J·mol^-1 , respectively. Thermodynamic parameters suggested that the process of interaction of PVP and DNA（Yb） 3 was driven by enthalpy. The results suggest that the primary interaction mode between PVP-Yb （Ⅲ ） complex and herring sperm DNA is groove binding.
出处
《西南科技大学学报》
CAS
2009年第2期1-4,共4页
Journal of Southwest University of Science and Technology
基金
国家自然科学基金项目(30572254)
