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
A novel method for preparation of polymer-based magnetic microspheres was proposed by utilizing melt reactive blending, which was based on selective location of Fe3O4 nanoparticles in PA6 domains of polystyrene （PS）...A novel method for preparation of polymer-based magnetic microspheres was proposed by utilizing melt reactive blending, which was based on selective location of Fe3O4 nanoparticles in PA6 domains of polystyrene （PS）/polyamide 6 （PA6） immiscible blends. The morphology of PA6/Fe3O4 composite magnetic mierospheres was studied by scanning electronic microscopy （SEM）. The composite magnetic mierospheres were spherical with a diameter range of 0.5-8 μm; the diameter was sharply decreased with a very narrow distribution by adding terminal maleic anhydride fimctionalized polystyrenes （FPS） for reactive blending. Transmission electron microscopy （TEM） and thermogravimetry analysis （TGA） results showed that most of Fe3O4 was located in the PA6 microspheres. Magnetization data revealed the magnetite content of PA6/Fe3O4 microspheres was about 32 wt% and the saturation magnetization could be up to 17.2 AmE/kg.展开更多
In inverse microemulsion, rare earth ferrite/polyacrylamide magnetic microsphere were prepared and their magnetic responsibility were studied by magnetic balance. Results indicate that the magnetic responsibility of m...In inverse microemulsion, rare earth ferrite/polyacrylamide magnetic microsphere were prepared and their magnetic responsibility were studied by magnetic balance. Results indicate that the magnetic responsibility of microsphere relates to magnetic moment of rare earth ion, and it can be improved by the addition of dysprosium ion of high magnetic moment. Dysprosium content has an effect on magnetic responsibility of dysprosium ferrite/polyacrylamide magnetic microsphere. The microsphere displays strong magnetic responsibility when the molar ratio of Dy3+/iron is 0.20.展开更多
Magnetic Fe304 nanoparticles were synthesized by co-precipitation method and the mercaptopurine （MER） drug-loaded magnetic microspheres were obtained through emulsion cross-linking methods. The efficiency of this ap...Magnetic Fe304 nanoparticles were synthesized by co-precipitation method and the mercaptopurine （MER） drug-loaded magnetic microspheres were obtained through emulsion cross-linking methods. The efficiency of this approach was evaluated in terms of drug loading content （DLC）, encapsulation efficiency （EE） and delivery properties in vitro, determined by high performance liquid chromatograph （HPLC）. The microspheres showed good DLC values of 11.8%, as well as good EE values of 79.4%. The in vitro drug release study was carried out in phosphate buffer solution （PBS） simulated body fluid, at 37 ~C with pH=7.4. The release profiles showed an initial fast release rate, which decreased as time progressed and about 84 % had been released after 48 h. The experimental results indicated that the prepared magnetic microspheres may be useful for potential applications of MER for magnetically targeted chemotherapy.展开更多
Non-porous superparamagnetic polymer microspheres with epoxy groups were prepared by dispersion polymerization of glycidyl methacrylate (GMA) in the presence of magnetic iron oxide (Fe3O4) nanoparticles coated with ol...Non-porous superparamagnetic polymer microspheres with epoxy groups were prepared by dispersion polymerization of glycidyl methacrylate (GMA) in the presence of magnetic iron oxide (Fe3O4) nanoparticles coated with oleic acid. The polymerization was carried out in the ethanol/water medium using polyvinylpyrrolidone (PVP) and 2,2’-azobisisobutyronitrile (AIBN) as stabilizer and initiator, respectively. The magnetic microspheres obtained were characterized with scanning electron microscopy (SEM), vibrating sample magnetometry (VSM) and Fourier transform infrared spectroscopy (FTIR). The results showed that the magnetic microspheres had an average size of-1μm with superparamagnetic characteristics. The saturation magnetization was found to be 4.5emu.g-1. There was abundance of epoxy groups with density of 0.028 mmol·g^-1 in microspheres. The magnetic PGMA microspheres have extensive potential uses in magnetic bioseparation and biotechnology.展开更多
This study aims to advance the development of magnetic fluorescent polymer microspheres for biomedical detection applications.Conventionally,dopants have utilized europium(Ⅲ)(Eu(Ⅲ))organic complexes due to their hig...This study aims to advance the development of magnetic fluorescent polymer microspheres for biomedical detection applications.Conventionally,dopants have utilized europium(Ⅲ)(Eu(Ⅲ))organic complexes due to their high compatibility with polymers and strong fluorescence.However,as the common magnetic material Fe_(3)O_(4)can quench their fluorescence,it is hard to synthesize Eu complexdoped magnetic fluorescent materials.To maintain fluorescence in the presence of magnetic parts,in this work,we synthesized Eu-doped magnetic microspheres with multi-layered structure.Firstly,poly-(glycidyl methacrylate)(PGMA)microspheres were prepared as templates and subsequently coated with layers of Fe_(3)O_(4)and SiO_(2).Then,the synthesized Eu(TTA)_(3)(TPPO)_(2)were added into PGMA@Fe_(3)O_(4)@SiO_(2)microspheres in either basic or acidic conditions,and covered them with an extra sol-gel layer of silica at the same time.The microspheres exhibit a core-shell structure with sub-micron dimensions(580 nm)and possess favorable superparamagnetic properties(M_(s)=22.02 A·m^(2)/kg,Mr=1.37 A·m^(2)/kg,H_(c)=0.242 A/m).But the fluorescence of Eu^(3+)are significantly quenched by Fe_(3)O_(4),O-H oscillators,and N-H oscillators.Finally,to exclude the quenching mentioned above,the first pure SiO_(2)shielding layer and the second Eu(TTA)_(3)(TPPO)_(2)-dispersed SiO_(2)layer were coated onto PGMA@Fe_(3)O_(4)microspheres to prevent the energy transfer due to the quenching centers and hold the fluorescence of Eu^(3+).These findings underscore the considerable potential of these microspheres exhibiting rapid magnetic separation and stable fluorescence for bioimaging and biosensing applications.展开更多
Macroporous magnetic poly(GMA-EGDMA-DVB) microspheres synthesized by suspension polymerization were used as supports for palladium catalyst.The results showed the novel magnetic catalyst can promote Heck reaction of a...Macroporous magnetic poly(GMA-EGDMA-DVB) microspheres synthesized by suspension polymerization were used as supports for palladium catalyst.The results showed the novel magnetic catalyst can promote Heck reaction of aryl halides with acrylic acid efficiently without an inert atmosphere.In addition,the novel catalyst can be conveniently recovered by applying an external magnet and reused at least five times without significant loss of its activity.展开更多
In this work, we demonstrate for the first time, a method to synthesize phenylboronic acid-Fe304@polydopamine （Fe3O4@ PDA-PBA） magnetic microspheres via the combination of mussel-inspired polydopamine coating and cl...In this work, we demonstrate for the first time, a method to synthesize phenylboronic acid-Fe304@polydopamine （Fe3O4@ PDA-PBA） magnetic microspheres via the combination of mussel-inspired polydopamine coating and click chemistry. Uniform-size and core-shell structured Fe3O4@PDA-PBA magnetic microspheres with a core diameter of -240 nm and a shell thickness of -13 nm were obtained as identified by the characterization of the morphology, structure and composition of the synthesized microspheres. We evaluated the selectivity and binding capacity of the Fe3O4@PDA-PBA magnetic microsphcres by using standard glycoproteins （ovalbumin, immunoglobulin G and catalase） and nonglycoproteins （human serum albumin, bovine hemoglobin, myoglobin, lysozyme, and ribonuclease A） as model proteins. Adsorption experiments, SDS-PAGE and mass spectrometry analysis demonstrated that the Fe3O4@PDA-PBA magnetic microspheres had much high binding capacity and selectivity for glycoproteins/glycopeptides compared to nonglycoproteins/nonglycopeptides. In addition, the practicability of the Fe3O4@PDA-PBA magnetic microspheres was further assessed by selective capture of glycoproteins from healthy hu- man serum. The good results demonstrated its potential in glycoproteome analysis.展开更多
The adriamycin magnetic microspheres (ADM-MAMs) were prepared by the heat-stabilized protein methods. Their physico-chemical properties were examined; their cytotoxicities against tumor cells in vitro were assayed by ...The adriamycin magnetic microspheres (ADM-MAMs) were prepared by the heat-stabilized protein methods. Their physico-chemical properties were examined; their cytotoxicities against tumor cells in vitro were assayed by a modi-fied MTT method, and their effects were observed on the implanted gastric tumor in Wistar rats given ADM-MAMs via alimentary canal at the presence of the ex-ternal magnetic fields. The results showed that the ADM-MAMs were successful-ly prepared and had cytotoxic effect on tumor cells in vitro similar to the free ADM (P>0. 05). The inhibitory effects of ADM-MAMs on the implanted gastric tumor in vivo were significantly increased as compared with the controls (P<0.01). Our results suggested that ADM-MAMs were a new type of adriamycin (ADM) preparation and its form alteration did not affect its anticancer effects.展开更多
Green and recyclable solid acid catalysts are in urgent demand as a substitute for conventional liquid mineral acids.In this work,a series of novel sulfonic acid-functionalized core-shell Fe_(3)O_(4)@carbon microspher...Green and recyclable solid acid catalysts are in urgent demand as a substitute for conventional liquid mineral acids.In this work,a series of novel sulfonic acid-functionalized core-shell Fe_(3)O_(4)@carbon microspheres(Fe_(3)O_(4)@C-SO_(3)H)have been designed and synthesized as an efficient and recyclable heterogeneous acid catalyst.For the synthesis,core-shell Fe_(3)O_(4)@RF(resorcinol-formaldehyde)microspheres with tunable shell thickness were achieved by interfacial polymerization on magnetic Fe_(3)O_(4)microspheres.After high-temperature carbonization,the microspheres were eventually treated by surface sulfonation,re sulting in Fe_(3)O_(4)@C-x-SO_(3)H(x stands for carbonization temperature)microspheres with abundant surface SO_(3)H groups.The obtained microspheres possess uniform core-shell structure,partially-graphitized carbon skeletons,superparamagnetic property,high magnetization saturation value of 10.6 emu/g,and rich SO_(3)H groups.The surface acid amounts can be adju sted in the range of 0.59-1.04 mmol/g via sulfonation treatment of carbon shells with different graphitization degrees.The magnetic Fe_(3)O_(4)@C-x-SO_(3)H microspheres were utilized as a solid acid catalyst for the acetalization reaction between benzaldehyde and ethylene glycol,demonstrating high selectivity(97%)to benzaldehyde ethylene glycol acetal.More importantly,by applying an external magnetic field,the catalysts can be easily separated from the heterogeneous reaction solutions,which later show well preserved catalytic activity even after 9 cycles,revealing good recyclability and high stability.展开更多
The magnetic gelatin-starch microspheres were prepared by modified emulsion cross-linking method with glutaraldehyde as the cross-linking agent. The structure, size distribution as well as morphology of magnetic micro...The magnetic gelatin-starch microspheres were prepared by modified emulsion cross-linking method with glutaraldehyde as the cross-linking agent. The structure, size distribution as well as morphology of magnetic microspheres were investigated by FT-IR spectrometer, dynamic laser scattering analyzer and scanning electron microscope, respectively. Bovine serum album(BSA)was chosen as model protein, and the adsorption processes were carried out under diversified conditions including BSA initial concentration, p H value, adsorption time and temperature to evaluate the performance of the magnetic microspheres. The average diameter of optimized spherical magnetic microspheres is 1.6 μm with excellent dispersivity, and the saturation magnetization is found to be equal to 1.056×10-2 A·m2. The adsorption isotherm of the BSA on the magnetic microspheres basically obeys the Langmuir model, with a maximum adsorption capacity of 120 mg/g and an adsorption equilibrium constant of 1.60 mL/mg.展开更多
The preparation and properties of adriamycin magnetic gelatin microspheres(Adr- MG-ms)were reported.The synthesis of magnetic iron oxide ultrafine particle and embolization effects of magnetic gelatin microspheres(MG-...The preparation and properties of adriamycin magnetic gelatin microspheres(Adr- MG-ms)were reported.The synthesis of magnetic iron oxide ultrafine particle and embolization effects of magnetic gelatin microspheres(MG-ms)in dog were studied.Adr- MG-ms consist of 2%(w/w)of adriamycin(Adr)as the core,and 68% of gelatin and 30% of magnetite as the shell with a mean particle size of 22 μm. In vitro experiment,the release rate of drug demonstrated that the microspheres have sustained-release properties.The average diameter of magnetic iron oxide was approximately l0 nm. Transcatheter embolization with MG-ms and ￣(99m)Tc-labelled MG-ms was performed under external magenet control in dog liver,respectively.Gamma photography and angiogram revealed that MG-ms level was almost equal both in left and right hepatic arteries without magnet,while with magnet(1200 Gs),MG-ms level in left hepatic artery(target site)was about 2.25 fold higher than in right hepatic artery,and few MG-ms in thyroid gland,brain and heart was observed.Results showed that the MG-ms is a promising embolic agent for treatment of hepatic cancer under external magnet control.展开更多
A novel phosphoprotein separation material was developed, which is constructed by a magnetic mesoporous Fe3 O4@TiO2（Fe3 O4@mTiO2） microsphere and a 5-aminoisophthalic acid（AIPA） monolayer that provides additional ...A novel phosphoprotein separation material was developed, which is constructed by a magnetic mesoporous Fe3 O4@TiO2（Fe3 O4@mTiO2） microsphere and a 5-aminoisophthalic acid（AIPA） monolayer that provides additional binding sites toward phosphate groups. The results of characteristic experiments demonstrated that Fe3 O4@mTiO2-AIPA had good dispersability, high magnetic susceptibility, and satisfactory grafting ratio of AIPA, ascribed to the large specific surface area of the inorganic substrate. Taking advantages of these features, Fe3 O4@mTiO2-AIPA was successfully utilized to separate α-casein（a typical phosphoprotein） and bovine serum albumin（BSA, a typical non-phosphoprotein） from their mixtures（molar ratio = 1:2）. Through adjusting pH and polarity of solutions, the BSA and α-casein were respectively enriched in washing fraction and elution fraction. This result displays the good potential of Fe3 O4@mTiO2-AIPA for application in phosphoprotein enrichment.展开更多
Amino-functionalized Fe3O4@mesoporous SiO/ core-shell composite microspheres NH2-MS in created in multiple synthesis steps have been investigated for Pb（Ⅱ） and Cd（Ⅱ） adsorption. The microspheres were characteriz...Amino-functionalized Fe3O4@mesoporous SiO/ core-shell composite microspheres NH2-MS in created in multiple synthesis steps have been investigated for Pb（Ⅱ） and Cd（Ⅱ） adsorption. The microspheres were characterized by transmission electron microscope （TEM）, scanning electron microscope （SEM）, N2 adsorption-desorption, zeta potential measurements and vibrating sample magnetometer. Batch adsorption tests indicated that NH2-MS exhibited higher adsorption affinity toward Pb（Ⅱ） and Cd（Ⅱ） than MS did. The Langmuir model could fit the adsorption isotherm very well with maximum adsorption capacity of 128.21 and 51.81 mg/g for Pb（Ⅱ） and Cd（Ⅱ）, respectively, implying that adsorption processes involved monolayer adsorption. Pb（Ⅱ） and Cd（Ⅱ） adsorption could be well described by the pseudo second-order kinetics model, and was found to be strongly dependent on pH and humic acid. The Pb（Ⅱ）- and Cd（Ⅱ）-loaded microspheres were effectively desorbed using 0.01 mol/L HC1 or EDTA solution. NH2-MS have promise for use as adsorbents in the removal of Pb（Ⅱ） and Cd（Ⅱ） in wastewater treatment processes.展开更多
Oleic acid was used as surface modification agent to improve the hydrophobicity of magnetic strontium hexaferrite particles. The structure and properties of treated magnetic particles were characterized by scanning el...Oleic acid was used as surface modification agent to improve the hydrophobicity of magnetic strontium hexaferrite particles. The structure and properties of treated magnetic particles were characterized by scanning electronic microscopy （SEM）, Fourier transform infrared spectra （FTIR）, powder X-ray diffraction （XRD） and magnetic property measurement system （MPMS）. The results show that oleic acid is chemically enwrapped on the surface of SrFe12O19 particles. Magnetic particles modified by oleic acid are highly dispersible and strongly responsive to magnetism but with slight decrease in saturated magnetization. The affinity between magnetic particles and monomers is improved by surface modification, resulting in increased particle incorporation in magnetic polymeric microspheres. The surface modification mechanism of magnetic particles by oleic acid is addressed in this work.展开更多
Using the technique of microemulsion polymerization with nano-reactor, dysprosium ferrite/polyacrylamide magnetic composite microsphere was prepared by one-step method in a single inverse microemulsion. The structure,...Using the technique of microemulsion polymerization with nano-reactor, dysprosium ferrite/polyacrylamide magnetic composite microsphere was prepared by one-step method in a single inverse microemulsion. The structure, average particle size, morphology of composite microsphere were characterized by FTIR, XRD, TEM and TGA. The magnetic responsibility of composite microsphere was also investigated. The results indicate that the magnetic composite microsphere possess high magnetic responsibility and suspension stability.展开更多
Nowadays,the employing of molecular imprinting technique in the analysis and separation of proteins from complex biological samples has been widely favored by researchers.To enrich the types of surface protein imprint...Nowadays,the employing of molecular imprinting technique in the analysis and separation of proteins from complex biological samples has been widely favored by researchers.To enrich the types of surface protein imprinted materials and expand the application fields of graphene materials,novel surface molecular imprinted polymers(MIPs)based on magnetic graphene microspheres Fe_(3)O_(4)@r GO@MIPs are first synthesized in this paper.Fe_(3)O_(4)@r GO@MIPs are prepared by oxidative self-polymerization of dopamine on the surface of magnetic graphene(Fe_(3)O_(4)@r GO)composite microspheres.Bovine serum albumin(BSA)is selected as protein template.Fe_(3)O_(4)@r GO microspheres with wrinkled flower-like structure are obtained by compounding Fe_(3)O_(4)and graphene oxide in an appropriate ratio via the method of high-temperature reduction self-assembly.The microspheres exhibit promising dispersibility,high external surface area,rich pore structure,and sufficient magnetic properties.These advantages not only prevent the agglomeration of imprinted microspheres in the aqueous phase,which is conducive to contact and static adsorption,but also increase the amount of protein imprinting.Additionally,sufficient magnetic properties ensure fast and effective separation of the adsorbents.While the adsorption capacity is increased,the separation procedure becomes simple.The binding capacity of Fe_(3)O_(4)@r GO@MIPs for BSA can reach 317.58 mg/g within 60 min,and the imprinting factor(IF)is 4.24.More importantly,Fe_(3)O_(4)@r GO@MIPs can specifically recognize the target BSA from the mixed proteins and the actual sample.There is no significant decrease in the adsorption amount,IF,and magnetic properties after eight runs.It is promising to be used in the separation of proteins from the actual biological samples.展开更多
Magnetically responsive hierarchical magnetite/silica/poly（ethyleneglycol dimethacrylate-co-4-vinylpyridine） （Fe3O4/SiO2/P（EGDMA-co-VPy）） tri-layer microspheres were used as stabilizers for gold metallic nanoeol...Magnetically responsive hierarchical magnetite/silica/poly（ethyleneglycol dimethacrylate-co-4-vinylpyridine） （Fe3O4/SiO2/P（EGDMA-co-VPy）） tri-layer microspheres were used as stabilizers for gold metallic nanoeolloids as a facilely recoverable catalyst with the reduction of 4-nitrophenol to 4-aminophenol as a model reaction. The magnetic microsphere stabilized gold metallic nanocolloids were prepared by in situ reduction of gold chloride trihydrate with borohydride as reductant via the stabilization effect of the pyridyl groups to gold nanoparticles on the surface of the outer shell-layer of the inorganic/polymer tri-layer microspheres.展开更多
The magnetic poly-（methacrylate-divinyl benzene） microspheres with micron size were synthesized by modified suspension polymerization method. Adsorption of Cr（VI） from aqueous solution by magnetic poly-（MA-DVB） ...The magnetic poly-（methacrylate-divinyl benzene） microspheres with micron size were synthesized by modified suspension polymerization method. Adsorption of Cr（VI） from aqueous solution by magnetic poly-（MA-DVB） microspheres with surface amination was investigated. The adsorption processes were carried out under diversified conditions of pH value, adsorption time and temperature to evaluate the perlbrmance of the magnetic microspheres. The optimum pH value for Cr（VI） adsorption was found as 3. The adsorption capacity increased with adsorption time and attained an optimum at 60 rain. The adsorption processes for magnetic microspheres was endothermic reaction, and the adsorption capacity increased with increasing temperature.展开更多
The targeting of antineoplastic agents to restricted anatomic sites and specific target cells have been challenged clinicians all the time in cancer chemotherapy, which resulted in recent efforts to focus the effects ...The targeting of antineoplastic agents to restricted anatomic sites and specific target cells have been challenged clinicians all the time in cancer chemotherapy, which resulted in recent efforts to focus the effects of existing antitumor agents and treatments on tumor cells and spare their effects on normal cells. The drug-carrier complex, adriamycin carried by magnetic albumin microspheres (ADM-MAM) was prepared by using our discovered new and modified method. The physical feature of the prepared drug-carrier microspheres was much better than by the traditional method in comparison. The successful preparation of the drug-carrier complex, ADM-MAM, is one of the key steps for our later further researches in the targeted chemotherapy.展开更多
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.
基金financially supported by the National Natural Science Foundation of China(Nos.50873033,20974033)
文摘A novel method for preparation of polymer-based magnetic microspheres was proposed by utilizing melt reactive blending, which was based on selective location of Fe3O4 nanoparticles in PA6 domains of polystyrene （PS）/polyamide 6 （PA6） immiscible blends. The morphology of PA6/Fe3O4 composite magnetic mierospheres was studied by scanning electronic microscopy （SEM）. The composite magnetic mierospheres were spherical with a diameter range of 0.5-8 μm; the diameter was sharply decreased with a very narrow distribution by adding terminal maleic anhydride fimctionalized polystyrenes （FPS） for reactive blending. Transmission electron microscopy （TEM） and thermogravimetry analysis （TGA） results showed that most of Fe3O4 was located in the PA6 microspheres. Magnetization data revealed the magnetite content of PA6/Fe3O4 microspheres was about 32 wt% and the saturation magnetization could be up to 17.2 AmE/kg.
文摘In inverse microemulsion, rare earth ferrite/polyacrylamide magnetic microsphere were prepared and their magnetic responsibility were studied by magnetic balance. Results indicate that the magnetic responsibility of microsphere relates to magnetic moment of rare earth ion, and it can be improved by the addition of dysprosium ion of high magnetic moment. Dysprosium content has an effect on magnetic responsibility of dysprosium ferrite/polyacrylamide magnetic microsphere. The microsphere displays strong magnetic responsibility when the molar ratio of Dy3+/iron is 0.20.
基金Funded by the Natural Science Foundation of Hubei Province(No.2011CDA056)the International Cooperation Funding of Hubei Province(No.2012IHA0120)+1 种基金the Fundamental Research Funds for the Central Universities of China(2012-IV-029)the Undergraduate innovation Funding of Wuhan University of Technology(136620004)
文摘Magnetic Fe304 nanoparticles were synthesized by co-precipitation method and the mercaptopurine （MER） drug-loaded magnetic microspheres were obtained through emulsion cross-linking methods. The efficiency of this approach was evaluated in terms of drug loading content （DLC）, encapsulation efficiency （EE） and delivery properties in vitro, determined by high performance liquid chromatograph （HPLC）. The microspheres showed good DLC values of 11.8%, as well as good EE values of 79.4%. The in vitro drug release study was carried out in phosphate buffer solution （PBS） simulated body fluid, at 37 ~C with pH=7.4. The release profiles showed an initial fast release rate, which decreased as time progressed and about 84 % had been released after 48 h. The experimental results indicated that the prepared magnetic microspheres may be useful for potential applications of MER for magnetically targeted chemotherapy.
基金Supported by 863 Hi-Technology Research and Development Program of China (No. G2002AA302211)the National Natural Science Foundation of China (No. 20206032).
文摘Non-porous superparamagnetic polymer microspheres with epoxy groups were prepared by dispersion polymerization of glycidyl methacrylate (GMA) in the presence of magnetic iron oxide (Fe3O4) nanoparticles coated with oleic acid. The polymerization was carried out in the ethanol/water medium using polyvinylpyrrolidone (PVP) and 2,2’-azobisisobutyronitrile (AIBN) as stabilizer and initiator, respectively. The magnetic microspheres obtained were characterized with scanning electron microscopy (SEM), vibrating sample magnetometry (VSM) and Fourier transform infrared spectroscopy (FTIR). The results showed that the magnetic microspheres had an average size of-1μm with superparamagnetic characteristics. The saturation magnetization was found to be 4.5emu.g-1. There was abundance of epoxy groups with density of 0.028 mmol·g^-1 in microspheres. The magnetic PGMA microspheres have extensive potential uses in magnetic bioseparation and biotechnology.
基金Project supported by the"Leading Goose"R&D Program(2022C01142)of Zhejiang Provincethe National Key R&D Program of China(2022YFB3503700)。
文摘This study aims to advance the development of magnetic fluorescent polymer microspheres for biomedical detection applications.Conventionally,dopants have utilized europium(Ⅲ)(Eu(Ⅲ))organic complexes due to their high compatibility with polymers and strong fluorescence.However,as the common magnetic material Fe_(3)O_(4)can quench their fluorescence,it is hard to synthesize Eu complexdoped magnetic fluorescent materials.To maintain fluorescence in the presence of magnetic parts,in this work,we synthesized Eu-doped magnetic microspheres with multi-layered structure.Firstly,poly-(glycidyl methacrylate)(PGMA)microspheres were prepared as templates and subsequently coated with layers of Fe_(3)O_(4)and SiO_(2).Then,the synthesized Eu(TTA)_(3)(TPPO)_(2)were added into PGMA@Fe_(3)O_(4)@SiO_(2)microspheres in either basic or acidic conditions,and covered them with an extra sol-gel layer of silica at the same time.The microspheres exhibit a core-shell structure with sub-micron dimensions(580 nm)and possess favorable superparamagnetic properties(M_(s)=22.02 A·m^(2)/kg,Mr=1.37 A·m^(2)/kg,H_(c)=0.242 A/m).But the fluorescence of Eu^(3+)are significantly quenched by Fe_(3)O_(4),O-H oscillators,and N-H oscillators.Finally,to exclude the quenching mentioned above,the first pure SiO_(2)shielding layer and the second Eu(TTA)_(3)(TPPO)_(2)-dispersed SiO_(2)layer were coated onto PGMA@Fe_(3)O_(4)microspheres to prevent the energy transfer due to the quenching centers and hold the fluorescence of Eu^(3+).These findings underscore the considerable potential of these microspheres exhibiting rapid magnetic separation and stable fluorescence for bioimaging and biosensing applications.
文摘Macroporous magnetic poly(GMA-EGDMA-DVB) microspheres synthesized by suspension polymerization were used as supports for palladium catalyst.The results showed the novel magnetic catalyst can promote Heck reaction of aryl halides with acrylic acid efficiently without an inert atmosphere.In addition,the novel catalyst can be conveniently recovered by applying an external magnet and reused at least five times without significant loss of its activity.
基金financial support from the National Natural Science Foundation of China(21005018,21375018 and 21075016)the National Basic Research Program of China(2010CB732403)+2 种基金the National Science Foundation for Fostering Talents in Basic Research of China(No.J1103303)the Doctoral Fund of Ministry of Education(20103514120002)the Program for Changjiang Scholars and Innovative Research Team in University(IRT1116)
文摘In this work, we demonstrate for the first time, a method to synthesize phenylboronic acid-Fe304@polydopamine （Fe3O4@ PDA-PBA） magnetic microspheres via the combination of mussel-inspired polydopamine coating and click chemistry. Uniform-size and core-shell structured Fe3O4@PDA-PBA magnetic microspheres with a core diameter of -240 nm and a shell thickness of -13 nm were obtained as identified by the characterization of the morphology, structure and composition of the synthesized microspheres. We evaluated the selectivity and binding capacity of the Fe3O4@PDA-PBA magnetic microsphcres by using standard glycoproteins （ovalbumin, immunoglobulin G and catalase） and nonglycoproteins （human serum albumin, bovine hemoglobin, myoglobin, lysozyme, and ribonuclease A） as model proteins. Adsorption experiments, SDS-PAGE and mass spectrometry analysis demonstrated that the Fe3O4@PDA-PBA magnetic microspheres had much high binding capacity and selectivity for glycoproteins/glycopeptides compared to nonglycoproteins/nonglycopeptides. In addition, the practicability of the Fe3O4@PDA-PBA magnetic microspheres was further assessed by selective capture of glycoproteins from healthy hu- man serum. The good results demonstrated its potential in glycoproteome analysis.
文摘The adriamycin magnetic microspheres (ADM-MAMs) were prepared by the heat-stabilized protein methods. Their physico-chemical properties were examined; their cytotoxicities against tumor cells in vitro were assayed by a modi-fied MTT method, and their effects were observed on the implanted gastric tumor in Wistar rats given ADM-MAMs via alimentary canal at the presence of the ex-ternal magnetic fields. The results showed that the ADM-MAMs were successful-ly prepared and had cytotoxic effect on tumor cells in vitro similar to the free ADM (P>0. 05). The inhibitory effects of ADM-MAMs on the implanted gastric tumor in vivo were significantly increased as compared with the controls (P<0.01). Our results suggested that ADM-MAMs were a new type of adriamycin (ADM) preparation and its form alteration did not affect its anticancer effects.
基金financially supported by the National Natural Science Foundation of China(Nos.21875044,52073064,22005058 and 22005057)National Key R&D Program of China(No.2020YFB2008600)+3 种基金Key Basic Research Program of Science and Technology Commission of Shanghai Municipality(No.20JC1415300)Program of Shanghai Academic Research Leader(No.19XD1420300)China Post-doctoral Science Foundation(Nos.2020M670973,BX20200085)the State Key Laboratory of Transducer Technology of China(No.SKT1904)。
文摘Green and recyclable solid acid catalysts are in urgent demand as a substitute for conventional liquid mineral acids.In this work,a series of novel sulfonic acid-functionalized core-shell Fe_(3)O_(4)@carbon microspheres(Fe_(3)O_(4)@C-SO_(3)H)have been designed and synthesized as an efficient and recyclable heterogeneous acid catalyst.For the synthesis,core-shell Fe_(3)O_(4)@RF(resorcinol-formaldehyde)microspheres with tunable shell thickness were achieved by interfacial polymerization on magnetic Fe_(3)O_(4)microspheres.After high-temperature carbonization,the microspheres were eventually treated by surface sulfonation,re sulting in Fe_(3)O_(4)@C-x-SO_(3)H(x stands for carbonization temperature)microspheres with abundant surface SO_(3)H groups.The obtained microspheres possess uniform core-shell structure,partially-graphitized carbon skeletons,superparamagnetic property,high magnetization saturation value of 10.6 emu/g,and rich SO_(3)H groups.The surface acid amounts can be adju sted in the range of 0.59-1.04 mmol/g via sulfonation treatment of carbon shells with different graphitization degrees.The magnetic Fe_(3)O_(4)@C-x-SO_(3)H microspheres were utilized as a solid acid catalyst for the acetalization reaction between benzaldehyde and ethylene glycol,demonstrating high selectivity(97%)to benzaldehyde ethylene glycol acetal.More importantly,by applying an external magnetic field,the catalysts can be easily separated from the heterogeneous reaction solutions,which later show well preserved catalytic activity even after 9 cycles,revealing good recyclability and high stability.
基金Project(GC201204)supported by the Open Fund of Guangdong Provincial Key Laboratory for the Green Chemicals,China
文摘The magnetic gelatin-starch microspheres were prepared by modified emulsion cross-linking method with glutaraldehyde as the cross-linking agent. The structure, size distribution as well as morphology of magnetic microspheres were investigated by FT-IR spectrometer, dynamic laser scattering analyzer and scanning electron microscope, respectively. Bovine serum album(BSA)was chosen as model protein, and the adsorption processes were carried out under diversified conditions including BSA initial concentration, p H value, adsorption time and temperature to evaluate the performance of the magnetic microspheres. The average diameter of optimized spherical magnetic microspheres is 1.6 μm with excellent dispersivity, and the saturation magnetization is found to be equal to 1.056×10-2 A·m2. The adsorption isotherm of the BSA on the magnetic microspheres basically obeys the Langmuir model, with a maximum adsorption capacity of 120 mg/g and an adsorption equilibrium constant of 1.60 mL/mg.
文摘The preparation and properties of adriamycin magnetic gelatin microspheres(Adr- MG-ms)were reported.The synthesis of magnetic iron oxide ultrafine particle and embolization effects of magnetic gelatin microspheres(MG-ms)in dog were studied.Adr- MG-ms consist of 2%(w/w)of adriamycin(Adr)as the core,and 68% of gelatin and 30% of magnetite as the shell with a mean particle size of 22 μm. In vitro experiment,the release rate of drug demonstrated that the microspheres have sustained-release properties.The average diameter of magnetic iron oxide was approximately l0 nm. Transcatheter embolization with MG-ms and ￣(99m)Tc-labelled MG-ms was performed under external magenet control in dog liver,respectively.Gamma photography and angiogram revealed that MG-ms level was almost equal both in left and right hepatic arteries without magnet,while with magnet(1200 Gs),MG-ms level in left hepatic artery(target site)was about 2.25 fold higher than in right hepatic artery,and few MG-ms in thyroid gland,brain and heart was observed.Results showed that the MG-ms is a promising embolic agent for treatment of hepatic cancer under external magnet control.
基金Funded by the National Natural Science Foundation of China(Nos.51473131,21275114,51533007 and 51521001)the Major State Basic Research Development Program of China(973 Program)(No.2013CB933002)+1 种基金Hubei Provincial Department of Education for Financial Assistance Through the “Chutian Scholar” ProgramHubei Provincial Natural Science Foundation of China(No.2014CFA039)
文摘A novel phosphoprotein separation material was developed, which is constructed by a magnetic mesoporous Fe3 O4@TiO2（Fe3 O4@mTiO2） microsphere and a 5-aminoisophthalic acid（AIPA） monolayer that provides additional binding sites toward phosphate groups. The results of characteristic experiments demonstrated that Fe3 O4@mTiO2-AIPA had good dispersability, high magnetic susceptibility, and satisfactory grafting ratio of AIPA, ascribed to the large specific surface area of the inorganic substrate. Taking advantages of these features, Fe3 O4@mTiO2-AIPA was successfully utilized to separate α-casein（a typical phosphoprotein） and bovine serum albumin（BSA, a typical non-phosphoprotein） from their mixtures（molar ratio = 1:2）. Through adjusting pH and polarity of solutions, the BSA and α-casein were respectively enriched in washing fraction and elution fraction. This result displays the good potential of Fe3 O4@mTiO2-AIPA for application in phosphoprotein enrichment.
基金supported by the National Natural Science Foundation of China (No. 21007048)the Key Projects in the National Science & Technology Pillar Program during the Twelfth Five-year Plan Period (No. 2012BAF03B06,2012BAJ25B06)partial fund of the State Key Laboratory of Pollution Control and Resource Reuse Foundation(No. PCRRY11011,PCRRF11003)
文摘Amino-functionalized Fe3O4@mesoporous SiO/ core-shell composite microspheres NH2-MS in created in multiple synthesis steps have been investigated for Pb（Ⅱ） and Cd（Ⅱ） adsorption. The microspheres were characterized by transmission electron microscope （TEM）, scanning electron microscope （SEM）, N2 adsorption-desorption, zeta potential measurements and vibrating sample magnetometer. Batch adsorption tests indicated that NH2-MS exhibited higher adsorption affinity toward Pb（Ⅱ） and Cd（Ⅱ） than MS did. The Langmuir model could fit the adsorption isotherm very well with maximum adsorption capacity of 128.21 and 51.81 mg/g for Pb（Ⅱ） and Cd（Ⅱ）, respectively, implying that adsorption processes involved monolayer adsorption. Pb（Ⅱ） and Cd（Ⅱ） adsorption could be well described by the pseudo second-order kinetics model, and was found to be strongly dependent on pH and humic acid. The Pb（Ⅱ）- and Cd（Ⅱ）-loaded microspheres were effectively desorbed using 0.01 mol/L HC1 or EDTA solution. NH2-MS have promise for use as adsorbents in the removal of Pb（Ⅱ） and Cd（Ⅱ） in wastewater treatment processes.
基金supported by Natural Science Foundation of Guangdong Province(no.04020114)Science and Technology Planning Project of Guangzhou City(2006J1-C0511).
文摘Oleic acid was used as surface modification agent to improve the hydrophobicity of magnetic strontium hexaferrite particles. The structure and properties of treated magnetic particles were characterized by scanning electronic microscopy （SEM）, Fourier transform infrared spectra （FTIR）, powder X-ray diffraction （XRD） and magnetic property measurement system （MPMS）. The results show that oleic acid is chemically enwrapped on the surface of SrFe12O19 particles. Magnetic particles modified by oleic acid are highly dispersible and strongly responsive to magnetism but with slight decrease in saturated magnetization. The affinity between magnetic particles and monomers is improved by surface modification, resulting in increased particle incorporation in magnetic polymeric microspheres. The surface modification mechanism of magnetic particles by oleic acid is addressed in this work.
文摘Using the technique of microemulsion polymerization with nano-reactor, dysprosium ferrite/polyacrylamide magnetic composite microsphere was prepared by one-step method in a single inverse microemulsion. The structure, average particle size, morphology of composite microsphere were characterized by FTIR, XRD, TEM and TGA. The magnetic responsibility of composite microsphere was also investigated. The results indicate that the magnetic composite microsphere possess high magnetic responsibility and suspension stability.
基金the National Natural Science Foundation of China(No.21704084,21975206)the Shaanxi Innovative Talents Promotion Plan-the Young Star of Science and Technology Project(No.2019KJXX-67)。
文摘Nowadays,the employing of molecular imprinting technique in the analysis and separation of proteins from complex biological samples has been widely favored by researchers.To enrich the types of surface protein imprinted materials and expand the application fields of graphene materials,novel surface molecular imprinted polymers(MIPs)based on magnetic graphene microspheres Fe_(3)O_(4)@r GO@MIPs are first synthesized in this paper.Fe_(3)O_(4)@r GO@MIPs are prepared by oxidative self-polymerization of dopamine on the surface of magnetic graphene(Fe_(3)O_(4)@r GO)composite microspheres.Bovine serum albumin(BSA)is selected as protein template.Fe_(3)O_(4)@r GO microspheres with wrinkled flower-like structure are obtained by compounding Fe_(3)O_(4)and graphene oxide in an appropriate ratio via the method of high-temperature reduction self-assembly.The microspheres exhibit promising dispersibility,high external surface area,rich pore structure,and sufficient magnetic properties.These advantages not only prevent the agglomeration of imprinted microspheres in the aqueous phase,which is conducive to contact and static adsorption,but also increase the amount of protein imprinting.Additionally,sufficient magnetic properties ensure fast and effective separation of the adsorbents.While the adsorption capacity is increased,the separation procedure becomes simple.The binding capacity of Fe_(3)O_(4)@r GO@MIPs for BSA can reach 317.58 mg/g within 60 min,and the imprinting factor(IF)is 4.24.More importantly,Fe_(3)O_(4)@r GO@MIPs can specifically recognize the target BSA from the mixed proteins and the actual sample.There is no significant decrease in the adsorption amount,IF,and magnetic properties after eight runs.It is promising to be used in the separation of proteins from the actual biological samples.
基金supported by the National Natural Science Foundation of China(No.20874049)
文摘Magnetically responsive hierarchical magnetite/silica/poly（ethyleneglycol dimethacrylate-co-4-vinylpyridine） （Fe3O4/SiO2/P（EGDMA-co-VPy）） tri-layer microspheres were used as stabilizers for gold metallic nanoeolloids as a facilely recoverable catalyst with the reduction of 4-nitrophenol to 4-aminophenol as a model reaction. The magnetic microsphere stabilized gold metallic nanocolloids were prepared by in situ reduction of gold chloride trihydrate with borohydride as reductant via the stabilization effect of the pyridyl groups to gold nanoparticles on the surface of the outer shell-layer of the inorganic/polymer tri-layer microspheres.
基金Supported by the National Basic Research Program of China (2007CB613507)
文摘The magnetic poly-（methacrylate-divinyl benzene） microspheres with micron size were synthesized by modified suspension polymerization method. Adsorption of Cr（VI） from aqueous solution by magnetic poly-（MA-DVB） microspheres with surface amination was investigated. The adsorption processes were carried out under diversified conditions of pH value, adsorption time and temperature to evaluate the perlbrmance of the magnetic microspheres. The optimum pH value for Cr（VI） adsorption was found as 3. The adsorption capacity increased with adsorption time and attained an optimum at 60 rain. The adsorption processes for magnetic microspheres was endothermic reaction, and the adsorption capacity increased with increasing temperature.
基金This project was supported by a grant from the NationalHealth Ministry(No.6 716 8)
文摘The targeting of antineoplastic agents to restricted anatomic sites and specific target cells have been challenged clinicians all the time in cancer chemotherapy, which resulted in recent efforts to focus the effects of existing antitumor agents and treatments on tumor cells and spare their effects on normal cells. The drug-carrier complex, adriamycin carried by magnetic albumin microspheres (ADM-MAM) was prepared by using our discovered new and modified method. The physical feature of the prepared drug-carrier microspheres was much better than by the traditional method in comparison. The successful preparation of the drug-carrier complex, ADM-MAM, is one of the key steps for our later further researches in the targeted chemotherapy.
