Carbon-coated Fe3O4（ Fe3O4/C） microspheres activated with 1-ethyl-3-（3-dimethylaminopropyl）-carbodiimide hydrochloride（EDC） were prepared, characterized and applied to adsorb bovine serum albumin（BSA）. The pre...Carbon-coated Fe3O4（ Fe3O4/C） microspheres activated with 1-ethyl-3-（3-dimethylaminopropyl）-carbodiimide hydrochloride（EDC） were prepared, characterized and applied to adsorb bovine serum albumin（BSA）. The prepared magnetic microspheres had spherical core-shell structure with a uniform and continuous carbon coating coupled with activation by EDC, and possessed superparamagnetic characteristics. The experimental results showed that the adsorption amount of BSA on the EDC-activated Fe3O4/C（Fe3O4/C-EDC） microspheres was higher than that on the Fe3O4/C microspheres. The maximum adsorption of BSA on Fe3O4/C-EDC microspheres occurred at pH 4.7, which was the isoelectric point of BSA. At low concentrations（below 1.0 M）, salt had no noticeable effect on BSA adsorption. The BSA adsorption of Fe3O4/C-EDC microspheres had a better fit to the Langmuir model than the Freundlich isotherm and Temkin isotherm model, and the kinetic data were well described by the pseudo-second-order model. The adsorption equilibrium could be reached within 20 min. High desorption efficiency（97.6%） of BSA from Fe3O4/C-EDC microspheres was obtained with 0.5 M Na2HPO4（pH 9.4） as the desorbent.展开更多
MnO2-impregnated carbon-coated Fe3 O4(Fe3O4/C/MnO2)nanocomposites with a good core-shell structure were prepared by direct oxidation of carbon-coated Fe3 O4(Fe3O4/C)microspheres with KMnO4 in alkaline solution and app...MnO2-impregnated carbon-coated Fe3 O4(Fe3O4/C/MnO2)nanocomposites with a good core-shell structure were prepared by direct oxidation of carbon-coated Fe3 O4(Fe3O4/C)microspheres with KMnO4 in alkaline solution and applied to adsorb bovine serum albumin(BSA).X-ray diffraction(XRD),transmission electron microscope(TEM),Fourier transform infrared spectrometer(FTIR),vibrating sample magnetometer(VSM)and thermogravimetric analyzer(TGA)tests show that Fe3O4/C microspheres were newly functionalized via the oxidation by KMnO4.Fe3O4/C/MnO2 nanocomposites exhibit a higher adsorption capacity for BSA than Fe3O4/C microspheres and the maximum adsorption of BSA on them occurs at pH 4.7,which is the isoelectric point of BSA.Langmuir isotherm model describes the adsorption of BSA better than Freundlich model and Temkin model,and the kinetics data fit well with the pseudo-second-order model.展开更多
基金Funded by the Major Science and Technology Program for Water Pollution Control and Treatment(No.2013ZX07202-010)
文摘Carbon-coated Fe3O4（ Fe3O4/C） microspheres activated with 1-ethyl-3-（3-dimethylaminopropyl）-carbodiimide hydrochloride（EDC） were prepared, characterized and applied to adsorb bovine serum albumin（BSA）. The prepared magnetic microspheres had spherical core-shell structure with a uniform and continuous carbon coating coupled with activation by EDC, and possessed superparamagnetic characteristics. The experimental results showed that the adsorption amount of BSA on the EDC-activated Fe3O4/C（Fe3O4/C-EDC） microspheres was higher than that on the Fe3O4/C microspheres. The maximum adsorption of BSA on Fe3O4/C-EDC microspheres occurred at pH 4.7, which was the isoelectric point of BSA. At low concentrations（below 1.0 M）, salt had no noticeable effect on BSA adsorption. The BSA adsorption of Fe3O4/C-EDC microspheres had a better fit to the Langmuir model than the Freundlich isotherm and Temkin isotherm model, and the kinetic data were well described by the pseudo-second-order model. The adsorption equilibrium could be reached within 20 min. High desorption efficiency（97.6%） of BSA from Fe3O4/C-EDC microspheres was obtained with 0.5 M Na2HPO4（pH 9.4） as the desorbent.
基金financially supported by the National Science and Technology Major Project of China for Water Pollution Control and Treatment(No.2013ZX07202-010)。
文摘MnO2-impregnated carbon-coated Fe3 O4(Fe3O4/C/MnO2)nanocomposites with a good core-shell structure were prepared by direct oxidation of carbon-coated Fe3 O4(Fe3O4/C)microspheres with KMnO4 in alkaline solution and applied to adsorb bovine serum albumin(BSA).X-ray diffraction(XRD),transmission electron microscope(TEM),Fourier transform infrared spectrometer(FTIR),vibrating sample magnetometer(VSM)and thermogravimetric analyzer(TGA)tests show that Fe3O4/C microspheres were newly functionalized via the oxidation by KMnO4.Fe3O4/C/MnO2 nanocomposites exhibit a higher adsorption capacity for BSA than Fe3O4/C microspheres and the maximum adsorption of BSA on them occurs at pH 4.7,which is the isoelectric point of BSA.Langmuir isotherm model describes the adsorption of BSA better than Freundlich model and Temkin model,and the kinetics data fit well with the pseudo-second-order model.
