双功能荧光——磁性复合微球的合成研究

双功能荧光-磁性复合微球同时具有荧光量子点和磁性颗粒的优良特性，在生物、化学、医学等交叉科学领域有着广阔的应用前景。本文综述了双功能荧光-磁性复合微球的合成方法，主要有包覆法、偶联法和种晶生长法，介绍了各自的优缺点，结合当前的研究现状，分析了其在制各双功能荧光-磁性复合微球方面的应用情况和仍需解决的问题。     

荧光硫量子点制备及应用研究进展

硫量子点具有发光强度高、毒性低和光化学性能稳定等优势，广泛应用于细胞成像、光电转换和化学催化等领域。鉴于此，本文系统综述了硫量子点的合成方法，光学性能和应用背景。硫量子点的合成方法可分为“自下而上法”和“自上而下法”，对比发现“自上而下法”合成的硫量子点具有更高的荧光量子产率。分析了硫量子点的光学性质，表明其具有紫外吸收特性、荧光特性、光致发光、电化学发光以及光学稳定性。最后，系统介绍了硫量子点在荧光探针、生物成像以及发光器件等领域的重要应用。基于以上分析，深刻剖析了当下硫量子点在前沿应用中亟待解决的问题，展望了未来硫量子点在生物医学、光电催化等新行业、新领域的发展方向。     

Fe_3O_4/MPTS@CdSe/CdS纳米离子的制备及其性能

经过修饰、加工处理过的纳米颗粒能够满足不同领域的应用需求,因此对纳米颗粒表面进行修饰成为纳米材料领域研究的热点问题。在水相内,通常使用化学共沉淀法制备Fe_3O_4纳米粒子,将其添加至正硅酸乙脂的醇水体系内,使磁性纳米粒子表面形成一层SiO_2包覆层,并采用丙基三甲氧基硅烷进行修饰处理,确保磁性纳米粒子表面连接丰富的功能双键,与乙二胺修饰后的CdSe/CdS量子点进行连接,制得磁性荧光双功能纳米微球,对其进行表征及其性能测试。实验结果证实,粒径为40nm的磁性纳米颗粒,饱和磁化强度为32.2emu/g,荧光强度是450a.u,磁性荧光双功能纳米材料在细胞分离、免疫检测等领域应用广泛。     

新型磁性荧光功能纳米复合物的制备及表征

在水相中,采用化学共沉淀法以FeCl_3·6H_2O和FeSO_4·7H_2O为原料合成了超顺磁性Fe3O4纳米粒子,并以甘氨酸、甲基丙烯酸甲酯进行修饰。CdSe/CdS量子点以巯基乙酸为稳定剂制得。最后以乙二胺为联接剂成功制得磁性荧光双功能纳米微球。并利用荧光显微镜、荧光分光光度计、红外、透射电子显微镜(TEM)和振动样品磁强计(VSM)对该微粒进行表征。结果表明,该微粒分散性好,磁性强度高,荧光性能优异。再将其与牛血清白蛋白(BSA)一起培育,表明其生物相容性良好。磁性荧光双功能纳米材料有望在靶向治疗、免疫检测、细胞分离和催化等领域得到广泛应用。     

磁性荧光纳米材料的合成

磁/荧光纳米复合材料是一种多功能纳米材料,既具有优良的磁性又具备荧光性能,在化学、生物、医药等领域具有广泛的应用。本文通过氧化沉淀法制备了磁性Fe3O4纳米粒子,通过水热法制备了碳量子点。最后制备了磁性/荧光复合纳米材料,并对产物进行了表征。     

Fe_3O_4-CdTe/CdS磁性荧光复合材料的制备

采用水相回流法制备出光谱可调的CdTe/CdS量子点,分别用透射电子显微镜(TEM)、能谱色散仪(EDS)、荧光分光光度仪对其形貌性能进行表征。用氨基聚倍半硅氧烷(NH_2-POSS)功能化CdTe/CdS量子点使其带有正电荷,再与带负电荷的Fe_3O_4磁性纳米粒子进行静电自组装,最终制备出磁性荧光复合材料(Fe_3O_4-CdTe/CdS)。并对量子点与氨基聚倍半硅氧烷的质量比、量子点与Fe_3O_4的质量比以及三者不同的组装顺序进行优化。结果表明,当量子点与氨基聚倍半硅氧烷和Fe_3O_4的质量比分别为6∶1和20∶1、组装顺序为量子点-氨基聚倍半硅氧烷-Fe_3O_4时得到复合材料的性能最佳。     

量子点的制备及其在生物医学中的应用进展

量子点作为一种优良的荧光半导体纳米粒子,已成为纳米技术领域最受关注的研究对象之一,并成功应用于生命科学等领域。随着小粒径的低毒无镉量子点的制备和量子点荧光共振能量转移等新技术的发展,量子点在生命科学领域将展示出更大的应用空间。本文介绍了量子点的基本概念和性质,探讨了近年来在有机溶剂和水溶液两种不同介质中制备量子点的方法,并分析比较了其优缺点;对量子点在生物医学领域(包括蛋白质和核酸研究、组分检测、荧光编码及细胞标记等)的应用进行了综述和展望,指出了目前存在的问题和今后的发展方向。     

巯基乙胺为稳定剂制备水溶性荧光量子点的合成探究

本文用巯基乙胺作为稳定剂分别利用了水相加热回流法、水热法两种方法制备出CdTe水溶性荧光量子点。这种荧光量子点可溶于水,且根据其特性可调控发射波长,发光性能较好。同时本文亦研究了在合成CdTe荧光量子点的过程中其反应温度、反应时间,pH环境等对于CdTe量子点发光性能的影响,以此甄选出最优化的量子点合成条件。     

碳量子点的光学性质及其应用研究进展

碳量子点是一种由碳原子组成的新型纳米结构,其粒径尺寸一般在10nm以下,具有很好的量子限域效应、荧光性能和光学性能等,有良好的应用前景。碳量子点在光催化反应中的作用主要体现在两个方面：作为电子接收器和用作太阳能电池光阳极的增敏剂。从荧光性能、光激发性、太阳能电池和光催化等方面总结了碳量子的荧光性质和光学性质,分析了碳量子点在光催化、太阳能电池和荧光转换等领域面临的挑战和问题。     

量子点荧光探针在生物医学领域的研究进展

量子点是一种新型的半导体荧光纳米材料,由于其特殊的纳米结构所导致的表面、介电、量子等效应而具有许多优异的光学性能,近年来在分析化学、生物医学等领域得以快速应用和发展.介绍了量子点的制备方法、表面修饰及量子点荧光探针在生物医学领域的应用进展,并对未来的发展方向作出了展望.     

磁性荧光复合纳米材料的研究进展

随着纳米科学技术的发展,科学工作者们已经成功制备出具有独特电、磁、光、热、生物、化学等性能的功能性纳米颗粒。这些功能性纳米颗粒对于生物、医学、电子、化学、材料等许多学科领域的发展具有重大意义,其中荧光量子点和磁性纳米材料因其独特的发光性能和磁学性能而引起广大科学工作者的兴趣。然而,随着科学技术的进一步发展,单一功能的材料已经不再满足人们对先进材料的需求,因此,具有磁性荧光双重功能的复合材料备受关注。本文概述了磁性荧光复合纳米颗粒的制备方法及其应用。     

磁性石墨烯复合材料制备与应用研究进展

石墨烯具备多种优异的性能,但容易通过π-π堆积和范德华力作用产生聚集,重新堆叠成石墨。为了改善石墨烯的堆叠问题,提高石墨烯材料的应用性,越来越多的研究者将石墨烯及其衍生物和磁性纳米粒子复合,制备综合性能更优的新型材料。本文结合近年来国内外研究报道,总结了磁性石墨烯纳米复合材料的制备方法（水热/溶剂热、化学接枝法、微波辅助法等）,概述了磁性石墨烯复合材料在环境样品分离富集、催化、涂层耐腐蚀性、吸波材料及能源等方面的应用,指出了目前磁性石墨烯复合材料研究中存在的一些问题,例如磁性颗粒容易发生团聚、生物安全性有待验证、氧化石墨烯的还原导致其表面吸附位点减少等。目前（氧化）石墨烯的制备工艺正在得到改善,而未来最重要的发展方向是加强对磁性石墨烯的表面改性,从而可使其表面具有更丰富的吸附位点,同时也可使石墨烯表面的磁性纳米粒子的形态及分布更均匀,更有利于稳定发挥磁性石墨烯的功能性。     

磁性介孔二氧化硅微球的研究及应用进展

磁性介孔二氧化硅微球作为一种新型纳米复合材料,广泛应用于众多领域.综述了近年来磁性介孔二氧化硅微球的制备方法,并对其在靶向药物、生物富集与分离、磁热疗、固定化酶等生化领域的应用作了介绍.     

Recent research progress on the preparation and application of magnetic nanospheres

Magnetic nanospheres have numerous applications in biomedicine, biotechnology and wastewater treatment, due to their high surface area, tunable sphere size and superparamagnetic properties. Magnetic nanoparticles can be designed and endowed with optical, electronic and fluorescent properties, allowing a wide range of functionality. Multifunctional magnetic particles with heterodimer structures allow various kinds of target molecules to be attached onto their specific parts via affinity or coordinate bonding, etc. The abilities of these nanodevices, including the encapsulation of target molecules in magnetic hybrid nanostructures and easy magnetic separation in the presence of external magnetic fields, show much promise for magnetic imaging, magnetic separation and drug delivery. Consequently, magnetic particles offer excellent potential future uses in disease diagnosis, hyperthermia, immunoassays, electrochemical biosensors, contaminated water treatment and optical detection. In this article, we review the preparation and application of inorganic and organic magnetic composite spheres in the fields of magnetic separation, drug delivery, hyperthermia, magnetic resonance imaging, and others. The size, specific surface area, structure, magnetic properties and surface functional groups of nanospheres have a great influence on their effectiveness in these applications. The encapsulation of target molecules in magnetic hybrid nanostructures and their easy separation using an external magnetic field show promise for the fabrication of novel nanodevices for many applications. Copyright © 2011 Society of Chemical Industry     

造纸用纳米粒子复合香豆素荧光乳液的制备及性能

以7-羟基-4-甲基香豆素为母核与丙烯酰氯反应,得到香豆素荧光单体。在乳化剂聚氧乙烯辛基苯酚醚-10(OP-10)与引发剂过硫酸铵的作用下,将其与丙烯酰胺、苯乙烯和改性纳米粒子经乳液聚合制备得到荧光乳液。采用红外光谱、核磁共振氢谱、粒径分析、紫外光谱、荧光光谱及紫外加速老化试验等对产物进行结构表征,光学性能研究及应用性能考察。结果表明,复合纳米粒子的荧光乳液粒径分布更加均匀,性质更稳定,且具有良好的光学性能, 涂覆于纸张表面,发现纸张白度得到改善,纸张强度和抗水性均大幅提高,且经过紫外老化后,发现目标产物有更好的抑制纸张返黄的作用。     

交联壳聚糖磁性微球制备及吸附性能研究

采用超声波辅助化学共沉淀法制备纳米Fe3O4,在此基础上选用乳化交联法,以戊二醛为交联剂,壳聚糖为单体包埋磁性纳米颗粒,合成了微米及纳米尺度上具有高吸附性、介质分离的磁性壳聚糖纳米微球(MCTS),并对复合材料的吸附性能进行了讨论。通过将壳聚糖包裹纳米磁性粒子制备成的磁性壳聚糖微球,具有比表面积大、多孔、易回收、可再生等优点,并且该磁性微球稳定性好、吸附性能强,有效地提高了壳聚糖的应用价值,而对于金属废水处理、药物的分离纯化和天然药物有效成分的富集纯化等意义重大。     

Preparation of albumin–ferrite superparamagnetic nanoparticles using reverse micelles

BACKGROUND: Micellar systems are widely applied as reactors to encapsulate inorganic nanoparticles in polymeric materials. However, only low inorganic contents and microscale dimensions are often achieved. RESULTS: The adsorption of albumin protein on ferrite nanoparticles permits to increase the stability of inorganic dispersions in water by inhibiting particle flocculation. Subsequent glutaraldehyde addition induces protein crosslinking and ferrite entrapment. Polymer–ferrite composite nanoparticles were obtained in this way. The magnetic albumin nanoparticles (25 nm mean diameter) obtained contain about 40 wt% of ferrite and show superparamagnetic behaviour. The composite powder was successfully functionalized with a model drug and the biological activity was evaluated. CONCLUSION: Using a reverse micelle approach, ferrite–albumin composite nanoparticles with a high inorganic content were obtained. The method permits the formulation of biocompatible magnetic particles of nanoscale dimensions. The exhibited superparamagnetic behaviour permits to hypothesize an application of the powder composite as a carrier in biomedical technologies. Copyright © 2009 Society of Chemical Industry     

Facile and efficient synthesis of magnetic fluorescent nanocomposites based on carbon nanotubes

Multifunctional nanomaterials composed of magnetic and fluorescent nanoparticles have been one of the most extensive pursuits because of the potential application in bio-research. In this paper, we demonstrated an efficient method by coupling CdSe/CdS/ZnS quantum dots (QDs) with Fe₃O₄ magnetic nanoparticles(MNPs) while functionalized multiwall carbon nanotubes (f-MWCNTs) were used as matrix to synthesize a kind of magnetic fluorescent nanocomposite. Compared with other matrix materials, carbon nanotubes have the advantages of high surface areas and good biocompatibility. The incorporation of f-MWCNTs supplies plenty of nucleation sites for the preferential growth of Fe₃O₄ nanoparticles, avoiding the agglomeration phenomenon of Fe₃O₄ MNPs in traditional co-precipitation method. Moreover, the un-reacted functional groups of f-MCNTs can further adsorb biological species and drugs, averting the decline of fluorescent intensity caused by the modification of biological species and drugs. The synthetic product maintains the unique properties of rapid magnetic response and efficient fluorescence, which shows a broad application prospect in fluorescent labeling, biological imaging, cell tracking and drug delivery.     

Highly selective fluorescent chemosensor for Zn2+ derived from inorganic-organic hybrid magnetic core/shell Fe3O4@SiO2 nanoparticles

ABSTRACT: Magnetic nanoparticles with attractive optical properties have been proposed for applications in such areas as separation and magnetic resonance imaging. In this paper, a simple and novel fluorescent sensor of Zn2+ was designed with 3,5-di-tert-butyl-2-hydroxybenzaldehyde [DTH] covalently grafted onto the surface of magnetic core/shell Fe3O4@SiO2 nanoparticles [NPs] (DTH-Fe3O4@SiO2 NPs) using the silanol hydrolysis approach. The DTH-Fe3O4@SiO2 inorganic-organic hybrid material was characterized by transmission electron microscopy, dynamic light scattering, X-ray power diffraction, diffuse reflectance infrared Fourier transform, UV-visible absorption and emission spectrometry. The compound DTH exhibited fluorescence response towards Zn2+ and Mg2+ ions, but the DTH-Fe3O4@SiO2 NPs only effectively recognized Zn2+ ion by significant fluorescent enhancement in the presence of various ions, which is due to the restriction of the N-C rotation of DTH-Fe3O4@SiO2 NPs and the formation of the rigid plane with conjugation when the DTH-Fe3O4@SiO2 is coordinated with Zn2+. Moreover, this DTH-Fe3O4@SiO2 fluorescent chemosensor also displayed superparamagnetic properties, and thus, it can be recycled by magnetic attraction.     

High-strength superparamagnetic composite fibers

The polymer composites of magnetic nanoparticles can be possibly used in a bulk form by preserving all the novel characteristics of magnetic nanoparticles such as superparamagnetic behavior. By introducing magnetic properties of Fe₃O₄ nanoparticles into polymer fibers, novel magnetic properties combine with the advantages of composite fibers such as light-weight and ease-of-use. Using dry-jet-wet fiber spinning technology, we have successfully fabricated iron oxide/polyacrylonitrile (Fe₃O₄/PAN) composite fibers with 10 wt% nanoparticle in the polymer matrix. Composite fiber with a diameter as small as 15 μm can achieve tensile strength and tensile modulus values as high as 630 MPa and 16 GPa, respectively. Superparamagnetic properties of Fe₃O₄ nanoparticles were preserved in the composite fibers with saturation magnetization at 80 emu/g and coercivity of 165 G.