RESUMO
A complex Eu(AA)3phen was synthesized and characterized by elemental analysis, IR spectroscopy and (1)H NMR. Interaction between Eu(AA)3phen and DNA was studied by UV/visible absorption spectroscopy, fluorescence spectrophotometer, circular-dichroism (CD) spectra and gel-electrophoresis measurements. Absorption spectral indicated that Eu(AA)3phen binding to DNA was an electrostatic mode, which was authenticated by the effect of ionic strength, thermal denaturation and fluorescence quenching experiments. The intrinsic binding constant Kb of Eu(AA)3phen was calculated to be 1.6×10(4) L mol(-1).
Assuntos
Acrilatos/química , DNA/química , Európio/química , Fenantrolinas/química , Absorção , Dicroísmo Circular , Eletroforese em Gel de Ágar , Indicadores e Reagentes , Desnaturação de Ácido Nucleico , Concentração Osmolar , Soluções , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , TemperaturaRESUMO
The microphase adsorption-spectral correction (MPASC) technique was described and applied to the study of the interactions of sodium octanesulfonate (SOS) with human serum albumin (HSA). The aggregation SOS obeys the Langmuir monolayer adsorption. The results show the adsorption ratio of sodium octanesulfonate to HSA is SOS:HSA=18:1.The adsorption constant is K(SOS-HSA)=4.03 × 10(2). The detection limit is 0.036µmol/L. FT-IR spectra proved the binding changed the conformation of HSA.
Assuntos
Ácidos Alcanossulfônicos/química , Albumina Sérica/química , Adsorção , Humanos , TensoativosRESUMO
A novel cationic polyhedral oligomeric silsesquioxane nanoparticle (cationic POSS) was synthesized and successfully used as a new probe for the detection of DNA by resonance light scattering technique (RLS). It was found that the electrostatic interaction of cationic POSS and DNA could obviously enhance the RLS signal, the enhanced RLS intensity at 360 nm was proportional to the concentration of nucleic acids within the range of 0.35-42.82 microg ml-1 for calf thymus DNA, the determination limit (3sigma) was 0.32 ng ml-1. The results showed this method was very sensitive, convenient, rapid and reproducible.
Assuntos
DNA/análise , Luz , Nanopartículas , Compostos de Organossilício , Espalhamento de RadiaçãoRESUMO
A mixed complex of La with 2,2-bipyridyl (dpy) and 1,10-phenanthroline(phen) was synthesized. Elemental analysis, IR and TGA of the complex were investigated, thus it was proved that the conformation of it was La(dpy)(phen)Cl3. The interaction of the complex with DNA has been studied also. The spectra showed that the interaction between La(dpy)(phen)Cl3 and DNA experienced intercalation of long-range self-assembly. The study made it clear that the synthesized mixed complex La(dpy)(phen)Cl3 can interact with DNA, and La(dpy)(phen)Cl3 can be used for probing a nucleic acid.
Assuntos
2,2'-Dipiridil/química , DNA/química , Lantânio/química , Conformação de Ácido Nucleico/efeitos dos fármacos , Fenantrolinas/química , 2,2'-Dipiridil/farmacologia , Dicroísmo Circular/métodos , Lantânio/farmacologia , Fenantrolinas/farmacologia , FotoquímicaRESUMO
A highly sensitive fluorimetry determination of DNA is developed in this paper. The maximum fluorescence intensity was produced in the pH 3.05, with the maximum excitation and emission wavelength of 362 and 531 nm, respectively. Under the optimum conditions, the fluorescence intensity was proportional to the concentration of DNA. The linear range for calf thymus DNA is of 0-120 mg.L-1. The limit of determination was 0.07 mg.L-1. When the proposed method was used to determine DNA in the presence of some coexisting substances, a satisfactory result was obtained.
