title: [K-35, a fluorescent probe for albumin study: optical properties].
abstract: Fluorescent probe N-(carboxyphenyl)imide of 4-(dimethylamino)naphthalic acid, K-35, is used as an indicator of structural changes of human serum albumin molecules in pathology. The probe occupies albumin binding pockets where the probe environment is of very high polarity; probably, the pocket(s) contains protein polar groups and water molecules. At the same time rather small Stokes shift of K-35 fluorescence spectrum shows that the polar group motion is of one-two order of value lower than mobility of polar molecules in polar fluids. K-35 fluorescence decay in HSA can be described as a sum of three exponentials with time constants close to tau1=9 ns; tau2=3.6 ns and tau3=1.0 ns. A difference between excitation maxima of these three decay components shows that environment of these three species of K-35 molecules has been different before excitation. Different r values are probably a consequence of non-identical structure of several binding sites, or a binding site(s) can have a variable conformation.
authors.forename: G E
authors.initials: GE
authors.lastname: Dobretsov
authors.forename: Iu A
authors.initials: IuA
authors.lastname: Gryzunov
authors.forename: T I
authors.initials: TI
authors.lastname: Syreĭshchikova
authors.forename: N V
authors.initials: NV
authors.lastname: Smolina
authors.forename: V Iu
authors.initials: VIu
authors.lastname: Svetlichnyĭ
authors.forename: B M
authors.initials: BM
authors.lastname: Poliak
mesh_terms: D001665:Binding Sites; D005456:Fluorescent Dyes / Q000737:chemistry*; D006801:Humans; D007094:Imides / Q000737:chemistry*; D009281:Naphthalenes / Q000737:chemistry*; D011487:Protein Conformation; D012709:Serum Albumin / Q000737:chemistry*; D013050:Spectrometry, Fluorescence
chemical_list: D005456:Fluorescent Dyes; D007094:Imides; C112259:N(n-carboxy)phenylimide-4-dimethyl-aminonaphthalic acid; D009281:Naphthalenes; D012709:Serum Albumin