[Interaction of ctDNA and EGCG-Cu(II) complex].
The fluorescence spectra, absorption spectra and resonance light scattering (RLS) spectra of EGCG-Cu((II) complex with nucleic acid were studied. Compared with the spectrum of EGCG-Cu(II), the spectrum of EGCG-Cu(II)-DNA system showed the following features: (1) in the fluorescence spectra, the peak did not shift, but the fluorescence intensity was enhanced and was proportional to the concentration of DNA. Under suitable conditions, EGCG-Cu(II) promised to be a probe for detecting DNA; (2) Absorption spectra of EGCG-Cu(II)-DNA system showed hyperchromicity; and (3) RLS of EGCG-Cu(II)-DNA system was enhanced also. A mechanism was suggested that the combination of nucleic acid and EGCG-Cu(II) complex was caused by intercalation and electrostatic force. An intercalation interaction between EGCG-Cu(II) and DNA enhanced the fluorescence intensity. Hyperchromicity of absorption spectra and RLS occurred because of electrostatic force. The effects of acid and ionic strength on fluorescence intensity were also discussed.
Wang
Dong-dong
DD
College of Animal Science/Beef Cattle Research Center, China Agricultural University, State Key Laboratory of Animal Nutrition, Beijing 100094, China.
Meng
Qing-xiang
QX
Chen
Dan-dan
DD
Ren
Li-ping
LP
Zhou
Zhen-ming
ZM
Mu
Hao-jie
HJ
D000818:Animals; D002392:Catechin / Q000031:analogs & derivatives* / Q000737:chemistry; D002417:Cattle; D003300:Copper / Q000737:chemistry*; D004247:DNA / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D015394:Molecular Structure; D013050:Spectrometry, Fluorescence; D013053:Spectrophotometry
D003300:Copper; D002392:Catechin; D004247:DNA; C427203:calf thymus DNA; C045651:epigallocatechin gallate