In weak acidic medium the alkaline cationic Safranine T interacts with acidic biological rnacromolecule heparin intensively causing the change of the molecular conformation, the maximum absorption wavelength and the a...In weak acidic medium the alkaline cationic Safranine T interacts with acidic biological rnacromolecule heparin intensively causing the change of the molecular conformation, the maximum absorption wavelength and the absorption value. The optimum experimental condition was given and a new method to determine the heparin was established. The linear range was 0.05-2.0 mg/L and the correlation coefficient was 0.9974. The method has been applied to analyze the samples and the results are satisfactory. Furthermore, the interaction mechanism was indicated.展开更多
By making use of the fluorescence quenching properties of safranine T(ST) in its long range assembly on the molecular surfaces of nucleic acids, the assembly number and constant of ST with calf thymus DNA, fish sperm ...By making use of the fluorescence quenching properties of safranine T(ST) in its long range assembly on the molecular surfaces of nucleic acids, the assembly number and constant of ST with calf thymus DNA, fish sperm DNA and yeast RNA were determined at 12℃. The corresponding free energy change, enthalpy change and entropy change of the long range assembly were calculated at the same temperature. It was found the assembly complexes are very stable and the assembly is a spontaneous process characterized an entropy increase.展开更多
The interaction between safranine T(ST) and yeast DNA was studied by means of UV absorption and fluorescence spectrometry. The wavelengths of fluorescence excitation and emission of ST were 520 nm and 570 nm, respecti...The interaction between safranine T(ST) and yeast DNA was studied by means of UV absorption and fluorescence spectrometry. The wavelengths of fluorescence excitation and emission of ST were 520 nm and 570 nm, respectively. The maximum absorption of UV spectrum was at 520 nm. Two kinds of interaction between ST and DNA, intercalation and electrostatic interaction, were conformed. The binding site size in DNA base pairs was 14.5±1.5 and the apparent binding constant was (2.81±0.11)×10 4 mol -1·L. The fluorescence quenching constant of DNA to ST was (1.52±0.19)×10 4 mol -1·L. A novel fluorescence analysis for DNA determination was presented and the effects of experimental conditions on the fluorescence quenching were discussed.展开更多
文摘In weak acidic medium the alkaline cationic Safranine T interacts with acidic biological rnacromolecule heparin intensively causing the change of the molecular conformation, the maximum absorption wavelength and the absorption value. The optimum experimental condition was given and a new method to determine the heparin was established. The linear range was 0.05-2.0 mg/L and the correlation coefficient was 0.9974. The method has been applied to analyze the samples and the results are satisfactory. Furthermore, the interaction mechanism was indicated.
文摘By making use of the fluorescence quenching properties of safranine T(ST) in its long range assembly on the molecular surfaces of nucleic acids, the assembly number and constant of ST with calf thymus DNA, fish sperm DNA and yeast RNA were determined at 12℃. The corresponding free energy change, enthalpy change and entropy change of the long range assembly were calculated at the same temperature. It was found the assembly complexes are very stable and the assembly is a spontaneous process characterized an entropy increase.
文摘The interaction between safranine T(ST) and yeast DNA was studied by means of UV absorption and fluorescence spectrometry. The wavelengths of fluorescence excitation and emission of ST were 520 nm and 570 nm, respectively. The maximum absorption of UV spectrum was at 520 nm. Two kinds of interaction between ST and DNA, intercalation and electrostatic interaction, were conformed. The binding site size in DNA base pairs was 14.5±1.5 and the apparent binding constant was (2.81±0.11)×10 4 mol -1·L. The fluorescence quenching constant of DNA to ST was (1.52±0.19)×10 4 mol -1·L. A novel fluorescence analysis for DNA determination was presented and the effects of experimental conditions on the fluorescence quenching were discussed.
