[The mechanism of carbofuran interacts with calf thymus DNA]

Carbofuran is an insecticide used on a variety of corps. Acute and chronic occupational exposure of humans to carbofuran has been observed to cause cholinesterase inhibition, but little is known about the interaction of carbofuran with DNA. Using the technique of UV spectrum and fluorescence quenching respectively, the interaction between carbofuran and ct DNA was studied. The UV spectrum showed that ct DNA can lead to the hypochromic effect and red shift of the UV spectrum of carbofuran. The quenching process was proved to be the single static quenching and quenching constant decreases with temperature increasing. The basis of this specificity is intercalation of insecticide between base pairs to produce ct DNA-carbofuran adducts. Furthermore, ethanol can produce Franck-condon effect on the ct DNA-carbofuran adducts. At different sodium chloride concentrations, quenching constant had no significant change, which appeared that there was little electrostatic interaction between ct DNA and carbofuran and it was intercalation.