1. College of Science, China Agricultural University，Beijing 100094, China 2. College of Resource and Environment, China Agricultural University，Beijing 100094, China
Abstract：The interaction between carbaryl and calf thymus DNA with Cu2+ was studied using fluorescence spectroscopy(FS) and UV spectrum. The quenching process was proved to be single static quenching and the quenching constant decreases with temperature increasing. The experimental results showed that the carbaryl can be intercalated into the twin-screw structure of calf thymus DNA, forming ctDNA-carbaryl adducts. The UV spectrum showed that ctDNA can also result in the increasing color and red shift. In the presence of Cu2+,it was discovered that the apparent association constant (Kα) increases and the binding sites number (n) of carbaryl molecules on ctDNA obviously increases. The interaction of the carbaryl and ctDNA was driven mainly by electrostatic force which was enhanced by Cu2+,thus the contribution of ΔH to ΔG increased in the presence of Cu2+. So the interaction between carbaryl and calf thymus DNA was enhanced via Cu2+.
Key words：Carbaryl;ctDNA;Interaction enhanced;Heavy metal
[1] Worthing C R, Hance R J. In the Pesticide Manual: A World Compendium. 7th ed, BCPC Berks，UK：Publications，1983. [2] Lechner D W，Abdelz-Rahman M S. Arch. Environ. Contam. Toxicol.，1985，14：451. [3] Bavari S，et al. Fundam. Appl. Toxicol.，1991，17：61. [4] ZHANG Li-jin, MIN Shun-geng, SUN Ying，et al(张立金, 闵顺耕, 孙 英，等). Environmental Chemistry(环境化学), 2004, 23(5): 520. [5] YANG Pin, GAO Fei(杨 频, 高 飞). The Principles of Bioinorganic Chemistry(生物无机化学原理). Beijing: Science Press(北京: 科学出版社), 2002. [6] LIU Xue-feng, XIA Yong-mei, FANG Yun, et al(刘雪锋, 夏咏梅, 方 云，等). Spectroscopy and Spectral Analysis(光谱学与光谱分析), 2005, 25(8): 1301. [7] ZHANG Li-jin, MIN Shun-geng, LI Guo-xue, et al(张立金，闵顺耕，李国学，等). Spectroscopy and Spectral Analysis(光谱学与光谱分析), 2005, 25(5): 739. [8] LU Ji-xin, ZHANG Yong, ZHANG Gui-zhu, et al(卢继新, 张 勇, 张贵珠，等). Journal of Analytical Science(分析科学学报), 2000, 16(6): 445. [9] Philip D Rossand, Sabramarian S. Biochemistry, 1981, 20: 3096. [10] Xia J L, Paul L D, Yesook K. J. Phys. Chem., 1992, 96: 6805.
