[Study of the interaction mechanism between brodifacoum and DNA by spectroscopy].
The interaction between brodifacoum (3-[3-(4'-bromophenyl-4) 1,2,3,4-tetralin-10]-4-hydroxyl-coumarin) (BDF), an anticoagulant rodenticide, and calf thymus DNA (ct-DNA) was studied by UV spectrum and fluorescence spectrum. The results were summarized as follows: There was a hypochromic effect of low concentration ct-DNA on the UV spectra. The fluorescence quenching studies showed a regular decrease in the fluorescence intensity after addition of ct-DNA by the static quenching mode with a quenching constant (Ksv) of 1.21 x 10(4) L x mol(-1) at 27 degrees C. The BDF possibly bonded to ct-DNA mainly via Van der Waals forces by the corresponding thermodynamics parameter. KI quenching experiment found that there was not obvious protection of ct-DNA to BDF. The fluorescence intensity of BDF/ct-DNA system changed with the variation in ionic strength Quenching of ct-DNA on the fluorescence of BDF/beta-CD inclusion complex was reduced in contrast with the free BDF, which showed that beta-CD could provide BDF with protection. So the comprehensive interaction mode of BDF with ct-DNA may be the groove binding by the above results. It was indicated that there had been static-electro interaction between BDF and ct-DNA at the same time. The conjunct action of Van der Waals forces and electrostatic attraction favorably provide BDF bonding interaction in the groove of ct-DNA.
Duan
Yun-qing
YQ
College of Science, China Agricultural University, Beijing 100094, China. dddy56@sina.com
Min
Shun-geng
SG
D015110:4-Hydroxycoumarins / Q000737:chemistry*; D000818:Animals; D002417:Cattle; D004247:DNA / Q000737:chemistry*; D007700:Kinetics; D012378:Rodenticides / Q000737:chemistry*; D013050:Spectrometry, Fluorescence / Q000379:methods
D015110:4-Hydroxycoumarins; D012378:Rodenticides; D004247:DNA; C427203:calf thymus DNA; C013418:bromfenacoum