免疫磁性纳米微球的制备与表征

成功制备了Fe3O4磁性纳米颗粒及二甲基丙烯酸乙二醇酯-甲基丙烯酸(EGDMA-MAA)共聚物包覆的Fe3O4磁性复合微球。将吲哚美辛抗体固定在复合微球表面,形成了Fe3O4(核)/聚合物-抗体(壳)的复合免疫磁性颗粒。XRD结果表明,制备的Fe3O4的晶型为反立方尖晶石型且纯度较高;TEM表征表明Fe3O4粒径较为均匀,平均粒径为12nm;磁性复合微球的平均直径为460nm。制备的Fe3O4磁性纳米颗粒和磁性复合微球有较强的磁响应强度,其饱和磁化率分别为49.16和8.38emu/g,能够满足磁性分离的要求。FT IR验证了磁性复合微球中羧基特征峰的存在,表明羧基成功连接在磁性微球上面。通过碳二亚胺/N-羟基琥珀酰亚胺(EDC/NHS)活化法将微球表面羧基活化并成功与抗吲哚美辛抗体交联。     

纳米Fe3O4/聚苯乙烯均匀分散体系的制备及结构

用化学共沉淀法制备了Fe3O4纳米颗粒,以油酸为表面活性剂,苯乙烯为载液,制备了稳定的纳米Fe3O4可聚合磁流体,将可聚合磁流体经自由基引发聚合制成纳米Fe3O4/聚苯乙烯均匀分散体系,用WAXRD研究了Fe3O4纳米粒子的结晶情况;用FTIR研究了油酸表面改性前后Fe3O4粒子表面官能团的变化;用TEM研究了Fe3O4颗粒的粒径大小及其在苯乙烯单体和聚苯乙烯中的分散情况;用DSC和TGA研究了纳米Fe3O4/聚苯乙烯均匀分散体系的玻璃化转变温度(Tg)和热稳定性,结果表明,合成的纳米Fe3O4为立方晶型,平均粒径在10nm左右,油酸分子在Fe3O4表面是化学吸附,经表面处理的Fe3O4超细颗粒在苯乙烯和聚苯乙烯基体中分散较均匀.界面粘结较好,含1.8％Fe3O4纳米颗粒的聚苯乙烯的最大热失重温度比聚苯乙烯提高了13K,Fe3O4/聚苯乙烯复合体系的饱和磁化强度σs为17.43emu/g.     

配体交换法制备水中高分散稳定性的多羧基修饰Fe3O4纳米颗粒

采用油相高温分解法制备了粒径可控且单分散的油溶性Fe3O4磁性纳米粒子(MNPs-OA), 并通过配体交换对其表面进行了亲水性修饰, 制备了柠檬酸(CA)、 N-(三甲氧基硅丙基)乙二胺三乙酸钠(SiCOOH)、 丁烷四羧酸(BTCA)和乙二胺四乙酸 (EDTA)四钠4种多羧基配体修饰的水溶性Fe3O4磁性纳米粒子(MNPs-CA, MNPs-SiCOOH, MNPs-BTCA 和MNPs-EDTA), 其中首次选用四羧基配体BTCA和EDTA四钠来修饰Fe3O4磁性纳米粒子(MNPs). 对油溶性MNPs和4种水溶性MNPs的形貌、 结构、 化学组成和磁性能进行了表征, 并对4种多羧基配体修饰的水溶性MNPs在水相中的稳定性和分散性进行了表征. 结果表明, 所得MNPs的平均粒径为15 nm, 具有超顺磁性, 配体交换后的水溶性MNPs具有良好的亲水性, 并在弱酸～碱性很宽的pH范围内具备良好的分散稳定性. 此类多羧基修饰的水溶性MNPs可与适当的阳离子聚电解质进行组装, 从而得到在磁靶向载体和磁共振造影(MRI)显影中具有良好应用前景的磁性自组装微囊.     

有机配体修饰纳米Al2O3的合成及性质研究

合成了以β-二酮配体3-甲基-1-苯基-4-(十八烷基酰基)吡唑啉酮-5(PMOP)修饰的Al2O3纳米粒子,并用IR、UV光谱、NMR和荧光光谱等手段进行了表征.修饰后的Al2O3纳米粒子能溶于氯仿、乙醇和甲苯等常见有机溶剂,并有较强的蓝色荧光.表明在一些无机纳米粒子的表面键合上有机配体后,可以产生新的光物理性质.修饰后的Al2O3纳米粒子还可作为支架材料用于准固态染料敏化纳米晶太阳能电池中.     

聚丙烯酰胺修饰Fe_3O_4磁性纳米粒子的制备与表征

首先通过化学处理在Fe3O4磁性纳米粒子表面引入Si—H键,然后通过选择性的硅氢加成反应制备了一个端基带溴的磁性引发剂,并利用原子转移自由基聚合(ATRP)技术,在该磁性引发剂表面接枝了聚丙烯酰胺高分子,该聚丙烯酰胺高分子展现出分子量高度可控性和窄的分子量分布.经聚丙烯酰胺修饰后Fe3O4磁性纳米粒子的比饱和磁化强度为58.5 emu.g-1,与未修饰纳米Fe3O4相比下降约20%.     

四氧化三铁磁性纳米微粒表面的氨基化修饰

以3-氨丙基三乙氧基硅烷(APTES)作为氨基化试剂,通过硅烷化反应使其键合于Fe3O4纳米颗粒表面,制备了表面氨基化的磁性Fe3O4纳米复合颗粒;利用红外光谱分析了产物的化学键合特征,利用电位滴定测定了合成产物表面的-NH2含量,探讨了活化方式、反应溶剂、投料比、温度、时间等因素对氨基化修饰效果的影响.结果表明,APTES成功地包覆在磁性Fe3O4纳米微粒表面;在乙醇-水体系中,在Fe3O4与APTES投料比3∶8、温度60℃下反应12h,得到的Fe3O4纳米颗粒表面APTES修饰效果最佳,表面-NH2含量高达1 400±50μmol·g-1.     

羧基化核壳磁性纳米Fe3O4吸附剂的制备及对Cu2+吸附性能

在以共沉淀法制备的磁性纳米Fe3O4粒子(Magnetic nanoparticles, MNP)表面进行了化学修饰, 制备了一种新型富含羧基功能团的核壳磁性纳米吸附剂(Carboxylic functionalized Fe3O4 magnetic nanoparticles, CMNP). 利用透射电子显微镜(TEM)、 X射线衍射仪(XRD)、 X射线能量色散谱(EDS)、 振动样品磁强计(VSM)、 傅里叶变换红外光谱(FIIR)和热重分析仪(TGA)对CMNP的形貌、 结构、 化学组成和磁性能进行了表征, 并考察了吸附剂对Cu2+的吸附性能, 研究了溶液pH值、 吸附时间和Cu2+初始浓度对吸附性能的影响. 结果表明, 羧基化核壳磁性纳米Fe3O4颗粒的平均粒径为15 nm, 具有良好的超顺磁性, 饱和磁化强度为41.84 A·m2/kg, 在10 min中内可达到吸附平衡, 在pH=7.0时吸附量最高, 吸附等温数据符合Langmuir模型, 饱和吸附量qm= 43.48 mg/g.     

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。     

SiO_2表面包覆对Fe_3O_4磁性微球性能的影响

采用化学共沉淀法制备Fe3O4磁性纳米粒子;用柠檬酸钠进行表面修饰得到在水相中稳定分散的Fe3O4溶胶。以Fe3O4磁性纳米粒子为种子,用碱催化正硅酸四乙酯水解、缩合制备了粒径和磁性可控的核壳结构的Fe3O4@SiO2复合微球。通过FT-IR,XRD,TEM,VSM和古埃磁天平对Fe3O4@SiO2复合微球进行表征。研究了SiO2包覆对Fe3O4@SiO2复合微球性能的影响。     

表面引发原子转移自由基聚合方法合成Fe3O4/PMMA复合纳米微粒

采用表面引发原子转移自由基聚合方法合成了核壳结构的磁性高分子纳米微粒. 作为聚合反应引发剂的3-氯丙酸, 首先与油酸修饰的Fe3O4纳米微粒表面的部分油酸置换, 然后在Fe3O4纳米微粒表面引发甲基丙烯酸甲酯聚合, 合成的纳米复合材料用TEM, FTIR, XRD和DSC表征. 磁性测试结果表明, 所制备的磁性高分子纳米微粒仍具有超顺磁性, 但由于聚合物的存在, 其饱和磁化强度降低.     

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.     

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p H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...     

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。     

Nanocomposite particles with core-shell morphology II. An investigation into the affecting parameters on preparation of Fe3O4-poly (butyl acrylate-styrene) particles via miniemulsion polymerization

The encapsulation of inorganic particles with polymers is desirable for many applications in order to improve the stability of the encapsulated products and disperse ability in different media. Colloidal particles with magnetic properties have become increasingly important both technologically and for fundamental studies. This is due to their tunable anisotropic. In the absence of an applied magnetic field, the particles have isotropic sphere dispersion, whereas in an external magnetic field the particles form anisotropic structures. Here, latexes containing nanocomposite particles of styrene-butyl acrylate/Fe₃O₄ with core-shell structure were prepared through miniemulsion polymerization technique. Magnetic composite nanospheres with high magnetic content were synthesized through miniemulsion polymerization using a new process based on a three-steps preparation route including two miniemulsion processes: (1) preparing a dispersion of oleic acid coated magnetite particles in water; (2) mixing of modified magnetite particles with styrene/butyl acrylate in the presence of sodium dodecyl sulfate (SDS), sorbitane mono oleate (Span 80), hexadecane (HD) and (3) miniemulsification of the modified Fe₃O₄ into the monomer droplets to reach to complete encapsulation. Subsequent polymerization generated magnetic nanocomposite spheres. Hence, the copolymerization reaction was performed on the surface of such particles in order to obtain core-shell morphology for these nanoparticles, which were characterized by several techniques such as TEM, SEM, DLS, TGA, VSM and FT-IR. The magnetic copolymer particles with diameter of 120-170 nm were obtained. The effect of several parameters such as magnetite, surfactants and hydrophobe amounts on the stability, particle size and magnetization were investigated and also optimized.     

纳米Fe_3O_4及钴离子掺杂Fe_3O_4:有机碱共沉淀制备和磁性质

以有机碱四甲基氢氧化铵(TMAH)为沉淀剂合成了纳米Fe3O4和Co2+掺杂的纳米Fe3O4粒子。分别讨论了碱用量,铁盐溶液浓度,反应温度,有机碱及PEG-4000的分散性等因素对纳米Fe3O4的形貌影响。结果表明,所合成的纳米Fe3O4为30nm左右的反尖晶石型面心立方结构,有机碱除了起沉淀剂作用,还能够提高纳米Fe3O4的分散性。本文还讨论了不同Co2+掺入量的纳米Fe3O4粒子的磁性质,结果表明Co2+掺杂的纳米Fe3O4粒子的矫顽力在不同掺入量的下有较大的改变。当Co2+掺入量为10.0%时,纳米Fe3O4的矫顽力达到最大值,为1628Oe。     

Development of Fe3O4-poly(l-lactide) magnetic microparticles in supercritical CO2

The Fe₃O₄-poly(l-lactide) (Fe₃O₄-PLLA) magnetic microparticles were successfully prepared in a process of solution-enhanced dispersion by supercritical CO₂ (SEDS), and their morphology, particle size, magnetic mass content, surface atom distribution and magnetic properties were characterized. Indomethacin (Indo) was used as a drug model to produce drug-polymer magnetic composite microparticles. The resulting Fe₃O₄-PLLA microparticles with mean size of 803 nm had good magnetic property and a saturation magnetization of 24.99 emu/g. The X-ray photoelectron spectroscopy (XPS) test indicated that most of the Fe₃O₄ were encapsulated by PLLA, which indicated that the Fe₃O₄-PLLA magnetic microparticles had a core–shell structure. After further loading with drug, the Indo-Fe₃O₄-PLLA microparticles had a bigger mean size of 901 nm, and the Fourier transform infrared spectrometer (FTIR) analysis demonstrated that the SEDS process was a typical physical coating process to produce drug-polymer magnetic composite microparticles, which is favorable for drugs since there is no change in chemistry. The in vitro cytotoxicity test showed that the Fe₃O₄-PLLA magnetic microparticles had no cytotoxicity and were biocompatible, which means there is potential for biomedical application.     

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.     

Self-assembly approach for the synthesis of electro-magnetic functionalized Fe3O4/polyaniline nanocomposites: Effect of dopant on the properties

Electro-magnetic functionalized Fe₃O₄/polyaniline (PANI) nanocomposites were synthesized by chemical oxidative polymerization in the presence of ammonium peroxydisulfate as an oxidizing agent. Polymerization was carried out independently using two different types of dopants, organic acids (camphorsulfonic acid (CSA) and p-toluenesulfonic acid (TSA)) and inorganic acid (hydrochloric acid). A plausible mechanism for the formation of the nanocomposites (NCs) is presented. During the formation of NCs, CSA/TSA also serves as a micellar template, whereas micelle formation is absent in the case of HCl. Fe₃O₄/PANI-CSA-NC, Fe₃O₄/PANI-TSA-NC and Fe₃O₄/PANI-HCl-NC were characterized for morphology, molecular structure, electrical conductivity and magnetic properties by transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), UV–visible spectroscopy (UV–vis) and superconductor quantum interference device (SQUID) measurements. The results indicate that dopant influence the properties of the NCs. TEM photographs of Fe₃O₄/PANI-CSA and Fe₃O₄/PANI-TSA reveal that the composite particles are spherical having a layer of PANI-CSA or PANI-TSA over Fe₃O₄ nanoparticles. Fe₃O₄/PANI-CSA-NC and Fe₃O₄/PANI-TSA-NC have better morphology, conductivity and high magnetic saturation (M_s) than that of Fe₃O₄/PANI-HCl-NC. Under applied magnetic field, the NCs exhibit the hysteresis loops of the ferromagnetic behavior. M_s value varies with content of Fe₃O₄ present in the composites.     

钛铁矿制备二氧化钛-四氧化三铁复合材料及其光催化应用

TiO_2因具有多种优异的特性被广泛应用在半导体光催化领域,但是纳米结构的TiO_2颗粒细微,在进行光催化反应之后,难以回收再利用。本文以廉价钛铁矿为原料制备光催化剂TiO_2,同时利用副产物铁合成Fe_3O_4,并采用简单温和的浸渍法制备Fe_3O_4/TiO_2磁性复合材料。通过XRD、FT-IR、SEM、EDS等手段对材料形态结构进行表征分析,并以光降解有机污染物若丹明B为探针反应,考察其光催化性能。结果表明,质量比为1∶10的Fe_3O_4/TiO_2复合材料结构稳定、分散均匀,具有最优的光催化活性(波长356nm下反应3h,若丹明B降解率达到64.0%),并表现出良好的重复性。同时,动力学结果显示降解符合一级反应动力学。