title: Spectroscopic studies on the interaction between tryptophan-erbium(III) complex and herring sperm DNA.
abstract: By means of UV and fluorescence spectra, the binding ratios between Er(III)-Trp and DNA in physiological pH environment (pH 7.40) were determined as n(Trp):n(Er(III))=3:1 and (n)ER(III)(Trp)(3):(n)(DNA) = 2:1, and the apparent molar absorptivity of epsilon(Er(III)-Trp-DNA) is 4.33 x 10(5) L mol(-1)cm(-1) which was confirmed by molar ratio method. The binding constants at different temperatures K(B25 degrees C)(theta)=1.93 x 10(4)L mol(-1) and K(B37 degrees C)(theta)=5.28 x 10(3)L mol(-1) were obtained by double reciprocal method. Thermodynamic function computation demonstrates that Delta(r)H(m)(theta) is the primary driving power of the interaction between Er(III)(Trp)(3) and DNA. By combination analysis of the Scatchard method and CD spectrometry, we suggested that the interaction mode between Er(III)(Trp)(3) complex and herring sperm DNA is groove and intercalation bindings.
authors.affiliation: Department of Chemistry, Material Science and Engineering College, Southwest University of Science and Technology, No. 59, Qinglong Road, Mianyang 621010, China.
authors.forename: Na
authors.initials: N
authors.lastname: Zhao
authors.forename: Xingming
authors.initials: X
authors.lastname: Wang
authors.forename: Haizhuan
authors.initials: H
authors.lastname: Pan
authors.forename: Yamin
authors.initials: Y
authors.lastname: Hu
authors.forename: Lisheng
authors.initials: L
authors.lastname: Ding
mesh_terms: D000165:Acridine Orange / Q000378:metabolism; D000818:Animals; D002942:Circular Dichroism; D004247:DNA / Q000378:metabolism*; D004871:Erbium / Q000378:metabolism*; D005399:Fishes; D008297:Male; D011687:Purines / Q000378:metabolism; D011743:Pyrimidines / Q000378:metabolism; D013050:Spectrometry, Fluorescence; D013094:Spermatozoa / Q000378:metabolism*; D044366:Transition Temperature; D014364:Tryptophan / Q000378:metabolism*; D014783:Viscosity
chemical_list: D011687:Purines; D011743:Pyrimidines; D004871:Erbium; D014364:Tryptophan; D004247:DNA; D000165:Acridine Orange