中文摘要：

研究了Tris-HCl（pH7.40）缓冲溶液中萤光素（F）与稀土金属离子Dy（Ⅲ）形成的配合物Dy（Ⅲ）（F）3与鲱鱼精DNA的相互作用机制,实验测得Dy（Ⅲ）（F）3与鲱鱼精DNA的结合比为5：1,表观摩尔吸光系数ε=1.14×105L·mol-1·cm-1,Dy（Ⅲ）（F）3与鲱鱼精DNA的结合常数K14℃=1.78×104L·mol-1,14℃时ΔrHm=1.03×104J·mol-1,ΔrSm=1.17×102J·mol-1·K-1,ΔrGm=-2.34×104J·mol-1.Dy（Ⅲ）（F）3与鲱鱼精DNA主要以部分嵌插和沟渠结合方式发生作用,作用过程为熵驱动.

英文摘要：

The mechanism of the interaction of fluorescein-Dy（Ⅲ）complex with herring sperm DNA was investigated in Tris-HCl buffer（pH 7.40）.It is calculated that the binding ratio of nDy（Ⅲ）（F）3：nDNAis 5：1,and the apparent molar absorptivity is 1.14×105 L·mol-1·cm-1.The bonding constant between Dy（Ⅲ）（F）3and DNA is 1.78×104 L·mol-1（14℃）and the themodynamic functions areΔrHm=1.03×104 J·mol-1,ΔrSm=1.17×102 J·mol-1·K-1,ΔrGm=-2.34×104 J·mol-1 at 14℃.The results confirm that the interaction between Dy（Ⅲ）（F）3complex and DNA is a partial intercalation and groove interaction,and the reaction process is entropy favorable.