[Study on the interaction of cobalt (II) polyamidomine dendrimer with DNA by spectrometry techniques].
Cobalt (II) polyamidomine dendrimer was prepared by the reaction of cobalt chloride, glyoxal and polyamidomine dendrimer of 5.0 generation. The interaction of cobalt (II) polyamidomine dendrimer complex with herring sperm (hsDNA) was carried out using methylene blue (MB) as the probe molecule by absorption and fluorescence spectroscopy and synchronous fluorescence spectroscopy. The results showed that the intensity of absorption peaks and fluorescence peaks increased when the complex interacted with hsDNA. The effect of sodium chloride showed that sodium ion can significantly constrain the interaction of cobalt(II) polyamidomine dendrimer with hsDNA. The curves indicated the competitive inhibition of MB binding to hsDNA in the presence of cobalt (II) polyamidomine dendrimer complexes, also MB could insert into interior of cobalt (II) polyamidomine dendrimer complexes. The results suggested that the complex mainly interacted with negatively charged phosphate moieties on hsDNA through electrostatic attraction and stacked on the surface of double stranded hsDNA, which may reduce the binding affinity of MB to hsDNA in the surrounding site. It was indicated that sodium ion might neutralize the negatively charged phosphate backbone of hsDNA, and then weaken the electrostatic attraction between complexes and hsDNA.
Li
Jin-Huan
JH
College of Chemistry and Materials Science, Shandong Agricultural University, Tai'an 271018, China. lijihn@163.com
Ai
Shi-Yun
SY
Shi
Wei-Jie
WJ
Yin
Huan-Shun
HS
Du
Hong-Xia
HX
D000042:Absorption; D000577:Amides / Q000737:chemistry*; D000818:Animals; D003035:Cobalt / Q000737:chemistry*; D004247:DNA / Q000378:metabolism*; D050091:Dendrimers / Q000737:chemistry*; D008751:Methylene Blue / Q000378:metabolism; D009942:Organometallic Compounds / Q000737:chemistry* / Q000378:metabolism*; D013050:Spectrometry, Fluorescence
D000577:Amides; D050091:Dendrimers; D009942:Organometallic Compounds; D003035:Cobalt; D004247:DNA; D008751:Methylene Blue