磁性贵金属纳米催化剂

磁性贵金属纳米颗粒因具有高效的催化性能和可重复利用性而受到广泛关注。本文描述了磁性贵金属纳米颗粒的基本结构,介绍了磁性贵金属催化剂的基本组成部分,概括了磁性贵金属纳米颗粒的制备方法,阐述了国内外磁性贵金属纳米颗粒的创新研究,指出了发展磁性贵金属纳米催化剂亟待解决的问题,并对磁性贵金属纳米颗粒的应用前景进行了展望。     

铁的氧化物纳米颗粒及其组装体的化学制备

铁的氧化物纳米颗粒作为一种重要的磁性纳米颗粒在磁记录材料、磁性液体、催化、尤其是生物医用领域有着广泛的应用前景,因而受到了研究者们极大的关注。本文对铁的氧化物磁性纳米颗粒的化学制备方法进行了综述,将其归结为复分解和热分解两种策略;总结了近期含铁的氧化物纳米颗粒组装体的研究进展,并对未来的发展做了展望。     

磁性金属-有机骨架复合材料的构建及在环境中的应用

磁性金属-有机骨架(MMOFs)复合材料是一类新颖的功能材料;MMOFs在磁性功能粒子的基础上结合了金属有机骨架材料的孔径均一、比表面积高、化学和热稳定性良好、吸附亲和力强等性能,在催化和环境等领域中显示出潜在的应用前景.本文简要概述了近年来制备的MMOFs复合材料,包括磁性微球核壳结构、磁性纳米颗粒镶嵌结构、磁性颗粒无规则互混结构、磁性石墨烯基复合结构;并从环境污染物的吸附、富集和催化降解角度,重点总结了MMOFs在环境分析和环境修复中的应用.     

蛋白功能化磁性纳米颗粒的制备及应用

蛋白功能化磁性纳米颗粒作为一种新型功能复合材料,已成为众多领域的研究热点。蛋白质在颗粒表面的稳定性、负载量及构象显著影响复合粒子的应用性能,而磁性纳米颗粒表面物化性质对颗粒的稳定性、分散性及磁性能对蛋白质的高效负载有重要影响。本文综述了磁性纳米颗粒表面修饰、蛋白功能化的方法以及蛋白在界面处构象变化的表征方法,介绍了蛋白功能化磁性纳米颗粒在酶催化合成、免疫分析检测及生物传感器等领域的应用,并对其未来的发展趋势进行了展望。     

核-壳结构磁性纳米颗粒负载离子液体的合成方法及应用*

离子液体具有良好的溶解能力、稳定性、结构可调性、无明显的蒸汽压等优点,使其可以作为良好的有机反应介质和催化剂,但由于其价格昂贵且不易从反应体系中分离,应用受到限制。以超顺磁性纳米颗粒作为催化剂载体,利用其所提供的磁学特性,可通过外磁场对催化剂进行简单有效的分离。不过,超顺磁性纳米颗粒具有的高比表面能以及粒子间的偶极距作用,使其容易团聚,不能稳定分散于反应体系。若在磁性纳米颗粒表面包裹一层有机物或无机物形成核-壳结构复合材料,就既可以阻止其团聚又可以对其进行表面功能化。因此,将离子液体固载到核-壳结构磁性纳米颗粒表面,制备可回收并循环使用的多相催化剂的工作受到广泛关注。本文综述了近十年来核-壳结构磁性纳米颗粒负载离子液体催化剂的制备方法及其在有机合成方面的应用,并对其未来的应用前景进行了展望。     

磁性氧化铁纳米颗粒——通向肿瘤磁共振分子影像的重要基石

本文根据近年来国内外发表的相关研究成果,总结了磁性氧化铁纳米晶体制备方面的研究进展,并以磁性氧化铁纳米颗粒在肿瘤磁共振分子影像领域中的应用为背景,阐述了肿瘤分子影像领域的未来发展趋势.     

磁性纳米复合材料的制备及在萃取富集中的应用

本文介绍了磁性纳米复合材料的制备、分类以及特性,综述了磁性纳米复合材料在分离富集无机物、有机物和生物大分子等中的应用,并对磁性纳米复合材料在分析领域中的应用前景进行了展望。引用文献85篇。     

单分散磁性纳米颗粒的制备及生物高分子在其上的组装

磁性纳米颗粒因其潜在的生物医学应用价值而成为纳米生物材料领域研究的前沿。本文综述了单分散磁性纳米颗粒的制备方法以及生物高分子在磁性纳米颗粒上的组装的研究进展。     

用于构建纳米生物探针的"clickable"金纳米粒子

近年来,纳米技术的在生命科学领域得到了广泛的应用,尤其是纳米粒子,如量子点、金纳米粒子、磁性纳米颗粒等,为生物医学分析提供了新的思路和强有力的工具.     

单个纳米颗粒的光散射检测技术进展

纳米颗粒因其在生物医学和生物分析领域具有重要的应用前景而备受关注.单个纳米颗粒的光散射检测技术是一种简单、有效地对纳米颗粒的尺寸、尺寸分布及浓度等进行表征的分析方法,尤其在揭露纳米颗粒的内在异质性方面具有独特优势.然而瑞利散射强度随粒径减小呈六次方衰减,使得小尺寸单个纳米颗粒的检测非常具有挑战性.本文对近年发展起来的多种单个纳米颗粒的光散射检测技术进行综述.     

Different methods for the fractionation of magnetic fluids

 Magnetic fluids are used in many fields of application, such as material separation and biomedicine. Magnetic fluids consist of magnetic nanoparticles, which commonly display a broad distribution of magnetic and nonmagnetic parameters. Therefore, upon application only a small number of particles contribute to the desired magnetic effect. In order to optimize magnetic fluids for applications preference is given to methods that separate magnetic nanoparticles according to their magnetic properties. Hence, a magnetic method was developed for the fractionation of magnetic fluids. Familiar size-exclusion chromatography of two different magnetic fluids was carried out for comparison. The fractions obtained and the original samples were also magnetically characterized by magnetic resonance and magnetorelaxometry, two biomedical applications. The size-exclusion fractions are similar to those of magnetic fractionation, despite the different separation mechanisms. In this respect, magnetic fractionation has several advantages in practical use over size-exclusion chromatography: the magnetic method is faster and has a higher capacity. The fractions obtained by both methods show distinctly different magnetic properties compared to the original samples and are therefore especially suited for applications such as magnetorelaxometry. Received: 12 July 1999/Accepted in revised form: 9 November 1999     

功能化磁性纳米粒子在乳状液制备及破乳中的应用及作用机制

功能化磁性纳米粒子因其独特的理化性质,在乳状液制备与破乳领域的应用受到广泛关注。本文归纳了功能化磁性纳米粒子的制备方法、合成结构与特征性质,阐述了其在乳状液制备及破乳中的应用过程,重点分析了磁性纳米粒子在溶液中良好分散、稳定吸附于油水界面排布为膜结构的作用行为,尤其是磁性纳米粒子的磁响应特征对乳状液中界面性质、液滴形貌及运动状态的影响,并进一步总结出其表面性质及作用行为对稳定乳状液或使乳状液破乳的规律。针对磁性纳米粒子对乳状液稳定性影响规律的探究可为其在应用领域提供理论支持。最后本文就功能化磁性纳米粒子研究中亟待解决的新问题作出展望。     

Enhanced modulation of magnetic field on surface plasmon coupled emission (SPCE) by magnetic nanoparticles

This article demonstrates the enhancement of magnetic nanoparticles on magnetic field modulation of surface plasmon coupled emission (SPCE), and this method is designed as a biosensor to prove the feasibility of magnetic field modulated SPCE to be employed in the field of biosensing and biodetection.     

Enhanced modulation of magnetic field on surface plasmon coupled emission (SPCE) by magnetic nanoparticles

The obvious enhancement effect of magnetic nanoparticles (MNPs) introduced in Cr/Co/Cr/Au substrate on the pulsed magnetic field-modulated surface plasmon coupled emission (SPCE) was investigated, and the observed enhancement factor was 4 comparing with the magnetic field modulated SPCE without MNPs. This is the new observation for the magnetic field modulated SPCE, and this method was designed as a biosensor, which to our knowledge, is the first application of magnetic field-modulated SPCE in biosensing and detection field. This strategy is a universal approach to increase the fluorescence signal and helps to build the new SPCE based stimulus-response system.     

Fabrication and Manipulation of Magnetic Composite Particles with Specific Shape and Size

The fabrication of microscale polyethylene glycol diacrylate(PEGDA) hydrogel particles was demonstrated via magnetic property ultraviolet(UV) lithography techniques, polydimethylsiloxane(PDMS) soft stamp pre-paration techniques and micro-nano imprint technology in this paper. The results of compositional and morphological characterizations of magnetic microparticles show that the Fe₃O₄ nanoparticles with an average diameter of 100 nm are uniformly dispersed in hydrogel. Owing to the excellent magnetism of Fe₃O₄ nanoparticles, the fabricated hydrogel microparticles with different sizes and shapes were manipulated in water via applying an external magnetic fields. Three types of motions, translation, rotation and flip, were demonstrated with the manipulator. These microscale magnetic PEGDA hydrogel particles have a great application potential in manufacturing process, micro/nanomotors, and machines.     

表面羧基化Fe3O4磁性纳米粒子的快捷制备及表征

亲水性磁性纳米颗粒在生物科学领域有着广泛应用,本研究提出了一种快速对磁性纳米粒子表面进行羧基化的方法. 首先使用氯化铁和氯化亚铁为原料, 以油酸为表面活性剂, 通过共沉淀法制得油酸包覆的亲油性磁性纳米粒子, 然后用高锰酸钾进行原位氧化, 将覆盖在粒子表面的油酸中的C＝C键氧化成-COOH, 从而得到单层羧基功能化的亲水性磁性纳米粒子. 利用透射电镜(TEM)、X射线衍射(XRD)、傅利叶红外光谱仪(FT-IR)、热重分析仪(TGA)、振动样品磁强计(VSM)、Zeta电位分析仪等对其进行表征. 结果表明磁性纳米粒子表面被成功羧基化,粒子的平均直径约为9 nm,饱和磁化值为64.5 emu/g,剩磁和矫顽力近似为零,具有典型的超顺磁性. 羧基化磁性纳米粒子可在pH7-10的水溶液中形成稳定分散的磁流体,保存6周无沉淀出现.     

Magnetoanalysis of micro/nanoparticles: a review

Application of magnetic field on the separation and analysis of nano/microparticles is a growing subject in analytical separation chemistry. The migration phenomenon of a particle under inhomogeneous magnetic field is called magnetophoresis. The migration velocity depends on the magnetic susceptibility and the size of a particle. Therefore, magnetophoresis allows us to determine the magnetic susceptibility of particles, and to separate particles based on the magnetic properties. Magnetic separation of ferromagnetic particles in liquid has been utilized for a long time. For example, a high gradient magnetic separation under the non-uniform magnetic field generated by ferromagnetic mesh has been utilized in a wide region from chemical industry to bioscience. Recent progress on magnetic nanoparticles and microfluidic devices has made it possible to extend the range of application. Furthermore, it has been demonstrated that the very sensitive measurement of the magnetic susceptibility of microparticles can be performed by observing magnetophoretic velocity. In this review, we mainly introduce novel separation and detection methods based on magnetophoresis, which have been invented in this decade, and then new principles of particle migration under magnetic field are presented.     

Magnetic hyperthermia: Potentials and limitations

Despite the fact that the magnetic hyperthermia (MH) has been known for more than 75 years, it is still debated in its clinical applications. The generation of a higher temperature at a tumor is called hyperthermia. There is a different of temperature ranges going from 39 to 40 ?°C up to such high temperatures as 80–90 ?°C. However, due to its high potential, MH is used along with nanoparticles as heat intermediaries in the treatment of cancer. Many Magnetic Nanoparticles (MNPs) with several properties and morphological metallic structures have been useful to magnetics hyperthermia therapy. These MNPs are categorized into two groups; magnetic alloy nanoparticles (MANPs) and magnetic metal oxide nanoparticles (MMONPs). The principal challenges of this method are the control of local tumoral temperature and the increase in nanoparticles heating power. The hyperthermia agents derived from magnetic nanoparticles along with magnetic field. In the recent study, hyperthermia thought, dissimilar types of magnetic nanoparticles for hyperthermia, efficacy for cancer therapy, advances, challenges, and future chances have been examined.     

磁性纳米粒子负载木瓜蛋白酶的制备、表征及用于果汁澄清(英文)

The preparation,characterization,and application of silica-coated magnetic nanoparticles for papain immobilization is reported.Papain was covalently attached onto the(3-chloropropyl) trimethoxysilane-modified silica-coated magnetic nanoparticles. The enzyme-immobilized nanoparticles were characterized by Fourier transform infrared spectroscopy,X-ray powder diffraction,scanning electron microscopy,and vibrating sample magnetometry techniques.Response surface methodology combined with statistical analyses using Minitab were employed to evaluate optimum operating conditions to immobilize papain on the magnetic nanoparticles.The optimum conditions were: temperature = 27.3℃,pH of the enzyme solution = 7.1,concentration of papain = 3.3 mg/mL,and immobilization time = 10 h.Compared with the free papain,the immobilized papain displayed enhanced enzyme activity,better tolerance to variations in the medium pH and temperature,improved storage stability,and good reusability.Both the free and immobilized enzymes were effective for the clarification of pomegranate juice.     

壳核型磁性纳米纤维素微球的超声制备及表征

A kind of cellulose magnetic nanoparticle with a core / shell structure has been prepared by ultrasonic irradiation. Cellulose acts as the shell while Fe3O4 magnetic nanoparticles take the role as the core. Magnetic force microscopy（MFM）with atomic force microscopy（AFM）measurement showed that the size of the magnetic nanoparticles is about 30-50 nm in diameter,while the Fe3O4 core is about 20-30 nm. FT-IR,XRD and MFM was used to provide the chemical and magnetic information of the nanoparticles. The MFM image showed that the nanoparticles separate very well with each other,indicating the cellulose shell produces a good prevention from the aggregation of the Fe3O4 particles. MFM studies also showed two magnetic nanoparticles can form particle-pairs,indicating a weak magneto-dipole interaction between magnetic nanoparticles. It is also found that the average sizes of magnetic nanoparticles have relation to the power of ultrasonic irradiation,and the possible mechanism is discussed.