Visible spectroscopic and electrochemical methods were used to study the interactions between DNA and fuchsin basic（FB）. FB has an irreversible electro-oxidation peak in 5 mmol/L Tris-HCl buffer solution at pH = 7.4...Visible spectroscopic and electrochemical methods were used to study the interactions between DNA and fuchsin basic（FB）. FB has an irreversible electro-oxidation peak in 5 mmol/L Tris-HCl buffer solution at pH = 7.4 on a glassy carbon electrode（GCE）. After adding certain concentration of dsDNA, the oxidation peak current of FB decreases, but the peak potential hardly changes. The visible absorption spectroscopic study shows that the binding mode of FB to dsDNA is intercalative binding and electrostatic binding when the ratio of the concentration of dsDNA to FB is smaller than 0. 2, and anew substance, which produces a new absorption peak, is obtained via a covalent binding between dsDNA and FB apart from intercalative binding and electrostatic binding when the ratio of the concentration of dsDNA to FB is larger than 0. 2. The visible absorption spectra varies no longer when the ratio of the concentration of dsDNA＇to FB is larger than 1.5. A mean binding ratio of dsDNA to FB was determined to be 1.4： 1, suggesting that two complexes FB-dsDNA and FB-2dsDNA be formed. The interaction between FB and ssDNA was only electrostatic binding. The more powerful interaction of FB with dsDNA than with ssDNA may be applied for the recognition of dsDNA and ssDNA, and in DNA biosensor as hybridization indicator.展开更多
Excessive discharge of dye wastewater has brought serious harm to human health and the environment.In this paper,a magnetic absorbent,ferroferric oxide@β-cyclodextrin(Fe_(3)O_(4)@CD),was prepared for the efficient ad...Excessive discharge of dye wastewater has brought serious harm to human health and the environment.In this paper,a magnetic absorbent,ferroferric oxide@β-cyclodextrin(Fe_(3)O_(4)@CD),was prepared for the efficient adsorption removal of basic fuchsin(BF)from dye wastewater,based on the special amphiphilicity ofβ-CD and the strong magnetism of Fe_(3)O_(4).A series of influence factors including the initial dye concentration,adsorbent dosage,temperature and pH were investigated,as well as the adsorption mechanism.The results show that Fe_(3)O_(4)@CD has the best adsorption and removal effect on BF dye at room temperature and neutral pH,when the initial concentration of dye is 25 mg/L and the adsorbent dosage is 100 mg.The adsorption behavior conforms to the pseudo-second-order kinetics and the Langmuir adsorption isotherm,and the adsorption process is spontaneously endothermic.Fe_(3)O_(4)@CD adsorbed with BF dye can be rapidly separated under an external magnetic field and then easily regenerated by HCl treatment.After 5 times of recycling,the removal rate of the prepared magnetic composite on BF dye is kept above 75%.This work will provide an economic and eco-friendly technology for the treatment of the actual dye wastewater.展开更多
Dosimetric characterization of aqueous solution of basic fuchsin was studied spectrophotometrically for possible application in the low-dose food irradiation dosimetry. Absorption spectra of unirradiated and irradiate...Dosimetric characterization of aqueous solution of basic fuchsin was studied spectrophotometrically for possible application in the low-dose food irradiation dosimetry. Absorption spectra of unirradiated and irradiated solu- tions were determined and the decrease in absorbance with the dose was noted down. Radiation-induced bleaching of the dye was measured at wavelengths of maximum absorption λmax (540nm) as well as 510nm and 460 nm. At all these wavelengths, the decrease in absorbance of the dosimeter was linear with respect to the absorbed dose from 50 Gy to 600 Gy. The stability of dosimetric solution during post-irradiation storage in the dark at room temperature showed that after initial bleaching during first ten to twenty days, the response was almost stable for about 34 days. The study on the effect of different light and temperature conditions also showed that the response gradually decreased during the storage period of 34 days, which shows that basic fuchsin dye is photosensitive as well as thermally sensitive.展开更多
文摘Visible spectroscopic and electrochemical methods were used to study the interactions between DNA and fuchsin basic（FB）. FB has an irreversible electro-oxidation peak in 5 mmol/L Tris-HCl buffer solution at pH = 7.4 on a glassy carbon electrode（GCE）. After adding certain concentration of dsDNA, the oxidation peak current of FB decreases, but the peak potential hardly changes. The visible absorption spectroscopic study shows that the binding mode of FB to dsDNA is intercalative binding and electrostatic binding when the ratio of the concentration of dsDNA to FB is smaller than 0. 2, and anew substance, which produces a new absorption peak, is obtained via a covalent binding between dsDNA and FB apart from intercalative binding and electrostatic binding when the ratio of the concentration of dsDNA to FB is larger than 0. 2. The visible absorption spectra varies no longer when the ratio of the concentration of dsDNA＇to FB is larger than 1.5. A mean binding ratio of dsDNA to FB was determined to be 1.4： 1, suggesting that two complexes FB-dsDNA and FB-2dsDNA be formed. The interaction between FB and ssDNA was only electrostatic binding. The more powerful interaction of FB with dsDNA than with ssDNA may be applied for the recognition of dsDNA and ssDNA, and in DNA biosensor as hybridization indicator.
基金Project(2017YFC1600306)supported by the National Key R&D Program of ChinaProject(21505005)supported by the National Natural Science Foundation of China+1 种基金Project(2018JJ2424)supported by the Hunan Provincial Natural Science Foundation,ChinaProject(2019IC21)supported by the International Cooperative Project for“Double First-Class”,China。
文摘Excessive discharge of dye wastewater has brought serious harm to human health and the environment.In this paper,a magnetic absorbent,ferroferric oxide@β-cyclodextrin(Fe_(3)O_(4)@CD),was prepared for the efficient adsorption removal of basic fuchsin(BF)from dye wastewater,based on the special amphiphilicity ofβ-CD and the strong magnetism of Fe_(3)O_(4).A series of influence factors including the initial dye concentration,adsorbent dosage,temperature and pH were investigated,as well as the adsorption mechanism.The results show that Fe_(3)O_(4)@CD has the best adsorption and removal effect on BF dye at room temperature and neutral pH,when the initial concentration of dye is 25 mg/L and the adsorbent dosage is 100 mg.The adsorption behavior conforms to the pseudo-second-order kinetics and the Langmuir adsorption isotherm,and the adsorption process is spontaneously endothermic.Fe_(3)O_(4)@CD adsorbed with BF dye can be rapidly separated under an external magnetic field and then easily regenerated by HCl treatment.After 5 times of recycling,the removal rate of the prepared magnetic composite on BF dye is kept above 75%.This work will provide an economic and eco-friendly technology for the treatment of the actual dye wastewater.
文摘Dosimetric characterization of aqueous solution of basic fuchsin was studied spectrophotometrically for possible application in the low-dose food irradiation dosimetry. Absorption spectra of unirradiated and irradiated solu- tions were determined and the decrease in absorbance with the dose was noted down. Radiation-induced bleaching of the dye was measured at wavelengths of maximum absorption λmax (540nm) as well as 510nm and 460 nm. At all these wavelengths, the decrease in absorbance of the dosimeter was linear with respect to the absorbed dose from 50 Gy to 600 Gy. The stability of dosimetric solution during post-irradiation storage in the dark at room temperature showed that after initial bleaching during first ten to twenty days, the response was almost stable for about 34 days. The study on the effect of different light and temperature conditions also showed that the response gradually decreased during the storage period of 34 days, which shows that basic fuchsin dye is photosensitive as well as thermally sensitive.
