Fe3O4@SiO2@polymer复合粒子的制备及在药物控制释放中的应用

本文通过多步反应制备了一种新型的、多层结构的、多功能的磁性纳米复合粒子, (Fe₃O₄@SiO₂@polymer). 纳米复合粒子内核是磁性Fe₃O₄纳米粒子, SiO₂包裹在Fe₃O₄上能够使其稳定分散和保护其不被腐蚀氧化; 中间层是生物相容的聚天冬氨酸(PAsp)载药层; 最外层是亲水的聚乙二醇(PEG)稳定层. 磁性纳米复合粒子各层都是生物相容的, 利用静电作用将抗癌药物阿霉素(DOX)负载在磁性纳米复合粒子中, 通过PAsp的pH响应调节了DOX的释放速率.     

柠檬酸根对纳米Fe3O4颗粒的生长及性能的影响

现代诊断学的发展使得超小超顺磁性的Fe₃O₄粒子在医学领域具有重要应用价值。实验中利用某些羧酸盐对铁氧化物晶粒成长的抑制作用，在共沉淀法中引入柠檬酸根，制备出平均粒径小于5 nm的Fe₃O₄纳米分散体系。研究了不同柠檬酸根浓度对生成粒子的大小、结晶和表面吸附情况的影响。对Fe₃O₄颗粒在不同条件下的磁性与胶体稳定性进行了讨论。     

棒状CuFe4Ox的可控合成及其异戊醇脱氢反应的催化性能

利用液相沉淀法可控合成了均匀的棒状CuFe₄O_x催化剂。通过原位X射线粉末衍射（XRD）、高分辨透射电子显微镜（TEM）及程序升温还原（TPR）等手段表征其晶相结构、形貌和还原性能。通过还原棒状CuFe₄O_x获得Cu⁰/Fe₃O₄ 纳米棒,原位X射线光电子能谱（XPS）用于确定Cu⁰/Fe₃O₄ 表面的相组成。通过液相沉淀法制备棒状CuFe₄O_x,在120℃保持3 h后加入Na₂CO₃溶液至pH等于9时所得棒状形貌最为规整。以异戊醇脱氢反应作为探针反应,比较了Cu⁰/Fe₃O₄ 纳米棒和Cu⁰/Fe₃O₄ 纳米颗粒的催化反应性能,发现Cu⁰/Fe₃O₄ 纳米棒比Cu⁰/Fe₃O₄ 纳米粒子具有更好的活性和稳定性,表明棒状Fe₃O₄ 担载的Cu纳米粒子具有更好的结构稳定性。     

棒状CuFe4Ox的可控合成及其异戊醇脱氢反应的催化性能

利用液相沉淀法可控合成了均匀的棒状CuFe₄O_x催化剂。通过原位X射线粉末衍射（XRD）、高分辨透射电子显微镜（TEM）及程序升温还原（TPR）等手段表征其晶相结构、形貌和还原性能。通过还原棒状CuFe₄O_x获得Cu⁰/Fe₃O₄纳米棒,原位X射线光电子能谱（XPS）用于确定Cu⁰/Fe₃O₄表面的相组成。通过液相沉淀法制备棒状CuFe₄O_x,在120℃保持3 h后加入Na₂CO₃溶液至pH等于9时所得棒状形貌最为规整。以异戊醇脱氢反应作为探针反应,比较了Cu⁰/Fe₃O₄纳米棒和Cu⁰/Fe₃O₄纳米颗粒的催化反应性能,发现Cu⁰/Fe₃O₄纳米棒比Cu⁰/Fe₃O₄纳米粒子具有更好的活性和稳定性,表明棒状Fe₃O₄担载的Cu纳米粒子具有更好的结构稳定性。     

不同形貌Fe3O4纳米粒子的氧化沉淀法制备与表征

用一种方法成功合成出了球体、四方体、八面体、不规则多面体、三角形和不规则颗粒等六种具有不同形貌的Fe₃O₄纳米粒子，通过扫描电子显微镜(SEM)表征了粒子形貌。试样经过X-射线衍射(XRD)表征具有尖晶石结构，且结晶良好。经震动样品磁强计(VSM)测定，各种形貌的Fe₃O₄纳米粒子都具有良好的磁性，其中八面体形貌的Fe₃O₄纳米粒子的饱和磁化强度达到86.56 emu·g^-1，剩磁为10.64 emu·g^-1，矫顽力为138 Oe。讨论了不同形貌的Fe₃O₄纳米粒子的形成机制，得出了晶核的生长环境对纳米粒子的形貌有重要影响的结论。     

用于高效去除水中孔雀石绿的三层结构磁性复合材料Fe3O4@聚丙烯酸@ZiF-8的制备

设计并合成了一种以磁性纳米粒子为核，聚合物为中间层，金属有机骨架材料为外层的三层结构磁性复合材料(Fe₃O₄@PAA@ZIF 8)。首先利用溶剂热法制备Fe₃O₄纳米粒子，然后通过蒸馏沉淀聚合法在Fe₃O₄纳米粒子表面包覆聚丙烯酸(PAA)层，最后通过原位沉积法在PAA外部包覆ZIF 8。在对Fe₃O₄@PAA@ZIF 8的组成和结构进行表征的基础上，深入研究其对孔雀石绿(MG)的吸附性能。透射电子显微镜(TEM)显示 Fe₃O₄@PAA@ZIF 8 具有明显的三层结构，Fe₃O₄的平均粒径为 117nm，PAA 层厚度约为 17 nm，ZIF 8层的厚度约为 14 nm。Fe₃O₄@PAA@ZIF 8对 MG 的吸附量随着 pH 的升高而增大，吸附过程符合准二阶动力学模型和 Langmuir等温吸附模型。此外，Fe₃O₄@PAA@ZIF 8还表现出良好的重复利用性能，8次循环利用后对MG(500 mg·L^-1)的最大吸附量仍可达982 mg·g^-1。     

Fe3O4纳米微球的溶剂热法合成及其对二甲酚橙的催化降解研究

以FeCl₃·6H₂O为单一铁源、1, 2-丙二醇为还原剂和溶剂、尿素为均相沉淀剂、顺丁烯二酸为添加剂, 通过简单一步溶剂热法于160℃制备出了形貌均一、单分散性好、尺寸约为200 nm的Fe₃O₄纳米微球。所制备的Fe₃O₄纳米微球不仅具有很高的磁化强度, 而且在利用过氧化氢氧化降解二甲酚橙(XO)的过程中显示出很好的催化活性。紫外可见分光光度法考察表明, 不加入Fe₃O₄催化剂时, 1 h内双氧水对二甲酚橙的脱色率仅为6.2%, 而加入Fe₃O₄纳米微球后, 双氧水对二甲酚橙的脱色率在1 h内即可达到100%, 循环使用10次后, Fe₃O₄纳米微球仍保持高的催化活性和结构稳定性。     

ATP适体接枝Fe_3O_4纳米粒子的制备及化学发光酶检测应用

制备了油酸修饰的Fe_3O_4纳米粒子,利用盐酸多巴胺对其表面进行氨基化改性,制得水分散性良好的Fe_3O_4纳米粒子,用X射线衍射、透射电镜、傅里叶变换红外光谱仪、振动样品磁强计和紫外-可见吸收光谱进行表征。随后,将氨基修饰的三磷酸腺苷(ATP)适体接枝到Fe_3O_4纳米粒子上,结合荧光素酶化学发光法进行ATP的定量检测,并应用于市售酸奶中乳酸菌ATP含量的检测,其灵敏度高、重现性好。各项实验结果表明所制备的Fe_3O_4纳米粒子是一种分散性好、易分离的载体,其粒径均一、稳定、磁性强、与适体结合性能好,拓展了Fe_3O_4纳米粒子在分析检测领域的应用。     

Au掺杂Fe3O4纳米粒子酶传感器的制备及其应用于有机磷农药检测的研究

合成了金掺杂的四氧化三铁纳米粒子(Au-Fe₃O₄), 以壳聚糖为交联剂, 制备了电流型乙酰胆碱酯酶(AChE)生物传感器, 并将其应用于有机磷农药(OPs)的检测. 实验表明, Au-Fe₃O₄纳米粒子具有良好的生物兼容性, 能够有效地促进电子传递, 修饰了Au-Fe₃O₄纳米粒子的酶传感器, 响应速度快, 检测灵敏度高, 稳定性好; 固定在传感器上的乙酰胆碱酯酶有良好的酶动力学响应, 其表观米氏常数( )为10.3 mmol/L. 利用有机磷农药对乙酰胆碱酯酶的抑制作用, 以硫代乙酰胆碱(ATCh)为底物, 对有机磷农药敌敌畏进行了检测, 检测限达到4.0×10^－13 mol/L.     

纳米四氧化三铁(Fe3O4)的制备和形貌

纳米Fe₃O₄因其特殊的理化性质和在生物医学领域潜在的应用价值而得到广泛研究。本文综述了纳米Fe3O4的制备方法，包括直流电弧等离子体法、热分解方法、沉淀法、水热法、电化学法、微乳液法、溶胶-凝胶法、有机物模板法、回流法等，结合作者在Fe3O4纳米粒子制备方面的最新工作，介绍了Fe3O4纳米粒子的新颖形貌。对纳米级Fe3O4制备研究的发展趋势进行了展望。     

磁靶向纳米Fe3O4-TiO2复合物的制备及其对肝癌细胞的光催化杀伤效应

采用三种低温溶胶-凝胶法制备了具有不同Fe₃O₄掺杂量的磁靶向纳米Fe₃O₄-TiO₂复合物, 通过X射线衍射(XRD)、透射电镜(TEM)、傅里叶变换红外(FTIR)光谱、紫外-可见(UV-Vis)光谱、荧光光谱(FS)及磁性能分析等表征方法筛选出包覆均匀、分散性好、磁性能优异及光催化活性较高的纳米Fe₃O₄-TiO₂复合物. 以四甲基偶氮唑蓝(MTT)法检测肝癌细胞(HepG2)的存活率, 考察纳米Fe₃O₄-TiO₂复合物在外磁场作用下对HepG2 细胞的光催化杀伤效应. 结果表明: 采用方法三制备的5%(质量分数)Fe₃O₄-TiO₂复合物具备核-壳结构, 在混悬液中分散性较好, 平均粒径约为50 nm, 具有较强的光催化活性和良好的磁响应性, 同时将纳米TiO₂的光响应范围拓宽至444 nm; 在外磁场作用下, 紫外光和可见光激发纳米Fe₃O₄-TiO₂复合物对HepG2细胞的杀伤效应差异不大, 且均强于纳米TiO₂; 其杀伤效应在0-1.0 T范围内随着外磁场强度的增大而增强.     

Ultrasonic synthesis of polyaniline nanotubes containing Fe3O4 nanoparticles

Polyaniline (PANI) nanotubes containing Fe₃O₄ nanoparticles were synthesized under ultrasonic irradiation of the aqueous solutions of aniline, ammonium peroxydisulfate (APS), phosphoric acid (H₃PO₄), and the quantitative amount of Fe₃O₄. It was found that the obtained samples had the morphologies of nanotubes. TEM images and selected area electronic diffractions showed that Fe₃O₄ nanoparticles were embedded in PANI nanotubes. We thought that the mechanism of the formation of PANI/Fe₃O₄ nanotubes could be attributed to the ultrasonic irradiation and the H₃PO₄-aniline salt template. The molecular structure of PANI/Fe₃O₄ nanotubes were characterized by Fourier transform infrared spectroscopy (FTIR), UV-vis absorption spectra and X-ray diffraction (XRD). The conductivity and magnetic properties of the PANI nanotubes containing Fe₃O₄ nanoparticles were also investigated.     

Hydrothermal synthesis of monodisperse Fe3O4 nanoparticles based on modulation of tartaric acid

In this paper, monodisperse Fe₃O₄ nanoparticles with single crystalline structure were synthesized via a facile environment-friendly method. And the size of the nanoparticles ranges from 10 nm to 15 nm. As-synthesized Fe₃O₄ were characterized by X-ray diffraction instrument (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR) spectrometer and field emission transmission electron microscope (FE-TEM). The effect of tartaric acid (TA) amount on products was investigated by XRD and TEM. The results indicated that TA could commendably modulate the crystalline phase, morphology and size of nanometer Fe₃O_4. A possible generated mechanism of Fe₃O₄ crystals was proposed in virtue of UV–vis absorption spectra. Besides, the magnetic properties of as-synthesized Fe₃O₄ were detected.     

Enhancing of asphaltene adsorption onto Fe3O4 nanoparticles coated with metal-organic framework Mil-101 (Cr) for the inhibition of asphaltene precipitation

In this study, the potential of MOF (Mil-101-Cr)-coated Fe₃O₄ magnetic nanoparticles (Fe₃O₄-MOF MNPs) for asphaltene adsorption was investigated for the first time and the results were compared with magnetic Fe₃O₄ nanoparticles (Fe₃O₄ MNPs). The coprecipitation method was used for the synthesis of both nanoparticles and were verified using x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and field emission scanning electron microscopy (FE-SEM). The initial asphaltene concentration, nanoparticles concentration, and temperature were the investigated parameters that influenced the adsorption capacity. Increasing the asphaltene concentration, decreasing the mass of nanoparticles, and reducing the temperature could enhance the maximum asphaltene adsorption capacities of 0.79 for Fe₃O₄ MNPs and 0.98?mg?m^?2 for Fe₃O₄-MOF MNPs. Adsorption isotherms tests showed that the Langmuir model was in agreement with the experimental data. In addition, the evaluation of adsorption kinetics demonstrated that the pseudo-second-order Lagergren model predicted the results more precisely. The amount of asphaltene adsorption for Fe₃O₄-MOF MNPs was higher than that for Fe₃O₄ MNPs. These results recommend the application of MOF as an appropriate and effective coating for enhancing asphaltene adsorption.     

叶酸对磁性Fe_3O_4纳米粒子的表面修饰

以FeCl3·6H2O作为单一铁源,1,6-己二胺作为胺化试剂,利用无模板的溶剂热方法制备了胺基功能化的磁性Fe3O4纳米粒子,并利用其键合叶酸分子,制备出表面修饰了叶酸的磁性Fe3O4复合纳米粒子。利用傅里叶变换红外光谱仪、X-射线衍射仪、透射电镜、差热-热重分析仪和振动样品磁强计对所得纳米粒子的形貌、粒径、化学组成和磁性能进行了表征。结果表明,叶酸分子通过化学键牢固键合在磁性纳米Fe3O4粒子表面,叶酸修饰的复合纳米粒子仍然具有良好的磁性能。     

A facile two-step modifying process for preparation of poly(SStNa)-grafted Fe3O4/SiO2 particles

This article reports the synthesis of the poly(sodium 4-styrenesulfonate)-grafted Fe₃O₄/SiO₂ particles via two steps. The first step involved magnetite nanoparticles (Fe₃O₄) homogeneously incorporated into silica spheres using the modified Stöber method. Second, the modified silica-coated Fe₃O₄ nanoparticles were covered with the outer shell of anionic polyelectrolyte by surface-initiated atom transfer radical polymerization. The resulted composites were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive microscopy (EDS), Fourier transform-infrared (FT-IR), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and vibration sample magnetometer (VSM). The XRD results indicated that the surface modified Fe₃O₄ nanoparticles did not lead to phase change compared with the pure Fe₃O₄. TEM studies revealed nanoparticles remained monodisperse. The detection of sulfur and sodium signals was a convincing evidence that sodium 4-styrenesulfonate was grafted onto the surface of the magnetic silica in XPS analysis. Finally, super-paramagnetic properties of the composite particles, and the ease of modifying the surfaces may make the composites of important use in mild separation, enzyme immobilization, etc.     

Amperometric Immunosensor Based on Gold Nanoparticles/Fe3O4-FCNTs-CS Composite Film Functionalized Interface for Carbofuran Detection

In this paper, a novel amperometric immunosensor for the determination of carbofuran based on gold nanoparticles (GNPs), magnetic Fe₃O₄ nanoparticles-functionalized multiwalled carbon nanotubes-chitosan (Fe₃O₄-FCNTs-CS), and bovine serum albumin (BSA) composite film was proposed. First, GNPs were immobilized onto the glassy carbon electrode (GCE) surface, and then the magnetic Fe₃O₄ nanoparticles mixed with chitosan-functionalized multiwall carbon nanotubes (CS-FCNTs) homogeneous composite (CS-FCNTs-Fe₃O₄) was immobilized onto the GNPs layer by electrostatic interactions between amino groups of CS and GNPs. Because chitosan (CS) contains many amino groups, it can absorb more antibodies. FCNTs have high surface area, high electrical conductivity, and it can enhance the electron transfer rate; Magnetite (Fe₃O₄) nanoparticles can provide a favorable microenvironment for biomolecules immobilization due to their good biocompatibility, strong superparamagnetic property, and low toxicity; and GNPs possess high surface-to-volume reaction, stability, and high conductivity. Gold Nanoparticles/Fe₃O₄-FCNTs-CS composite film was constructed onto the GCE surface, which had significant synergistic effects toward immunoreaction signal amplification. The stepwise assembly process was characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), respectively. Under the optimal conditions, the current response was proportional to the concentration of carbofuran ranging from 1.0 ng/mL to 100.0 ng/mL and from 100.0 ng/mL to 200 µg/mL with the detection limit 0.032 ng/mL. The proposed immunosensor exhibited good accuracy, high sensitivity, and stability, and it can be used for detection of carbofuran pesticide.     

Facile synthesis of multifunctional attapulgite/Fe3O4/polyaniline nanocomposites for magnetic dispersive solid phase extraction of benzoylurea insecticides in environmental water samples

In this study, the superparamagnetic attapulgite/Fe₃O₄/polyaniline (ATP/Fe₃O₄/PANI) nanocomposites were successfully synthesized by a one-pot method. Fe (III) was applied as both the oxidant for the oxidative polymerization of aniline and the single iron source of Fe₃O₄ formed by the redox reaction between aniline and Fe (III). The ATP/Fe₃O₄/PANI was used as sorbent for magnetic dispersive solid phase extraction (MDSPE) of benzoylurea insecticides (BUs) in environmental water samples. The as-prepared nanocomposite sorbents were characterized by Fourier transform infrared spectra (FT-IR), X Ray diffraction (XRD), scanning electron microscopy(SEM), transmission electron microscopy (TEM), and vibrating sample magnetometry. Various experimental parameters affecting the ATP/Fe₃O₄/PANI-based MDSPE procedure, including the composition of the nanocomposite sorbents, amount of ATP/Fe₃O₄/PANI nanocomposites, vortex time, pH, and desorption conditions were investigated. Under the optimal conditions, a good linearity was observed for all target analytes, with correlation coefficients (r²) ranging from 0.9985 to 0.9997; the limits of detection (LOD) were in the range of 0.02–0.43 μg L⁻¹, and the recoveries of analytes using the proposed method ranged between 77.37% and 103.69%. The sorbents exhibited an excellent reproducibility in the range of 1.52–5.27% in extracting the five target analytes. In addition, the intra-day and inter-day precision values were found to be in the range of 0.78–6.86% and 1.66–8.41%, respectively. Finally, the proposed ATP/Fe₃O₄/PANI-based MDSPE method was successfully applied to analyze river water samples by rapid preconcentration of BUs.     

静电自组装方法合成的具有多孔三维网络结构的Fe3O4/石墨烯复合材料作为高性能锂离子电池负极材料

采用静电自组装方法,分两步合成Fe（OH）₃/GO前驱体（GO：氧化石墨烯）,再通过水热反应和600 ℃高纯氮气气氛下煅烧,获得了Fe₃O₄/石墨烯复合材料. 通过X射线衍射（XRD）、扫描电镜（SEM）、高分辨透射电镜（HRTEM）、拉曼（Raman）光谱等多种分析,发现该复合材料具有三维多孔石墨烯网络结构. 把合成的这种Fe₃O₄/石墨烯复合材料作为锂离子电池负极材料,电化学测试结果表明其具有优良的电化学性能：首次放电容量为1390 mAh·g^-1,50次循环后容量为819 mAh·g^-1. 通过对比实验表明,三维石墨烯网络结构的形成对复合材料的电化学循环稳定性起着关键作用.