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1.
Zhongguo Zhong Yao Za Zhi ; 45(11): 2601-2610, 2020 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-32627495

RESUMO

Gardeniae Fructus has the traditional effects of promoting intelligence and inducing resuscitation, but its mechanism is unclear. In this study, the relationship between Gardeniae Fructus's traditional effect of promoting intelligence and inducing resuscitation and anti-Alzheimer's disease effect was taken as the starting point to investigate the anti-Alzheimer's disease mechanism of the major absorbed components in Gardeniae Fructus by the network pharmacology method. The network pharmacology research model of "absorbed composition-target-pathway-disease" was adopted. In this study, the active components screening and target prediction technology were used to determine the active components and targets of Gardeniae Fructus in treatment of Alzheimer's disease. The enrichment pathway and biological process of Gardeniae Fructus were studied by using the bioinformatics annotation database(DAVID), and the results of molecular docking validation network analysis were used to elaborate the mechanism of Gardeniae Fructus in treatment of Alzheimer's disease. It was found that 35 absorbed components of Gardeniae Fructus not only regulated 48 targets such as cholines-terase(BCHE) and carbonic anhydrase 2(CA2), but also affected 11 biological processes(e.g. transcription factor activity, nuclear receptor activity, steroid hormone receptor activity, amide binding and peptide binding) and 7 metabolic pathways(MAPK signaling pathway, Alzheimer disease and estrogen signaling pathway, etc.). Molecular docking results showed that more than 60% of the active components could be well docked with key targets, and the relevant literature also showed that the active components could inhibit the MAPK1 expression of key targets, indicating a high reliability of results. These results indicated that Gardeniae Fructus may play its anti-Alzheimer's disease action via a "multi-ingredients-multi-targets and multi-pathways" mode, providing a scientific basis for further drug research and development.


Assuntos
Doença de Alzheimer , Medicamentos de Ervas Chinesas , Gardenia , Humanos , Simulação de Acoplamento Molecular , Reprodutibilidade dos Testes
2.
ACS Appl Mater Interfaces ; 7(16): 8377-92, 2015 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-25845677

RESUMO

Reversible protein phosphorylation is a key event in numerous biological processes. Mass spectrometry (MS) is the most powerful analysis tool in modern phosphoproteomics. However, the direct MS analysis of phosphorylated proteins/peptides is still a big challenge because of the low abundance and insufficient ionization of phosphorylated proteins/peptides as well as the suppression effects of nontargets. Enrichment of phosphorylated proteins/peptides by affinity materials from complex biosamples is the most widely used strategy to enhance the MS detection. The demand of efficiently enriching phosphorylated proteins/peptides has spawned diverse affinity materials based on different enrichment principles (e.g., electronic attraction, chelating). In this review, we summarize the recent development of various affinity materials for phosphorylated proteins/peptides enrichment. We will highlight the design and fabrication of these affinity materials, discuss the enrichment mechanisms involved in different affinity materials, and suggest the future challenges and research directions in this field.


Assuntos
Fosfopeptídeos/análise , Fosfoproteínas/análise , Proteômica/métodos , Nanocompostos/química , Fosforilação
3.
Anal Chim Acta ; 812: 65-73, 2014 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-24491766

RESUMO

A simple, fast, efficient, and reusable microwave-assisted tryptic digestion system which was constructed by immobilization of trypsin onto porous core-shell Fe3O4@fTiO2 microspheres has been developed. The nanostructure with magnetic core and titania shell has multiple pore sizes (2.4 and 15.0 nm), high pore volume (0.25 cm(3) g(-1)), and large surface area (50.45 m(2) g(-1)). For the proteins, the system can realize fast and efficient microwave-assisted tryptic digestion. Various standard proteins (e.g., cytochrome c (cyt-c), myoglobin (MYO), ß-lactoglobulin (ß-LG), and bovine serum albumin (BSA)) used can be digested in 45 s under microwave radiation, and they can be confidently identified by mass spectrometry (MS) analysis; even the concentration of substrate is as low as 5 ng µL(-1). Furthermore, the system for the 45 s microwave-assisted tryptic digestion is still effective after the trypsin-immobilized microspheres have been reused for 5 times. Importantly, 1715 unique proteins from 10 µg mouse brain proteins can be identified with high confidence after treatment of 45 s microwave-assisted tryptic digestion.


Assuntos
Microesferas , Tripsina/química , Compostos Férricos/química , Espectrometria de Massas , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Micro-Ondas , Proteínas/química , Espectrometria por Raios X , Titânio/química , Difração de Raios X
4.
J Colloid Interface Sci ; 417: 217-26, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24407680

RESUMO

In this work, novel magnetic polymeric core-shell structured microspheres with immobilized Ce(IV), Fe3O4@SiO2@PVPA-Ce(IV), were designed rationally and synthesized successfully via a facile route for the first time. Magnetic Fe3O4@SiO2 microspheres were first prepared by directly coating a thin layer of silica onto Fe3O4 magnetic particles using a sol-gel method, a poly(vinylphosphonic acid) (PVPA) shell was then coated on the Fe3O4@SiO2 microspheres to form Fe3O4@SiO2@PVPA microspheres through a radical polymerization reaction, and finally Ce(IV) ions were robustly immobilized onto the Fe3O4@SiO2@PVPA microspheres through strong chelation between Ce(IV) ions and phosphate moieties in the PVPA. The applicability of the Fe3O4@SiO2@PVPA-Ce(IV) microspheres for selective enrichment and rapid separation of phosphopeptides from proteolytic digests of standard and real protein samples was investigated. The results demonstrated that the core-shell structured Fe3O4@SiO2@PVPA-Ce(IV) microspheres with abundant Ce(IV) affinity sites and excellent magnetic responsiveness can effectively purify phosphopeptides from complex biosamples for MS detection taking advantage of the rapid magnetic separation and the selective affinity between Ce(IV) ions and phosphate moieties of the phosphopeptides. Furthermore, they can be effectively recycled and show good reusability, and have better performance than commercial TiO2 beads and homemade Fe3O4@PMAA-Ce(IV) microspheres. Thus the Fe3O4@SiO2@PVPA-Ce(IV) microspheres can benefit greatly the mass spectrometric qualitative analysis of phosphopeptides in phosphoproteome research.


Assuntos
Cério/química , Complexos de Coordenação/química , Óxido Ferroso-Férrico/química , Fosfopeptídeos/isolamento & purificação , Humanos , Imãs , Microesferas , Fosfopeptídeos/sangue , Ácidos Fosforosos/química , Polivinil/química , Dióxido de Silício/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectroscopia de Infravermelho com Transformada de Fourier , Fatores de Tempo
5.
J Mater Chem B ; 2(39): 6886-6892, 2014 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-32261885

RESUMO

Magnetic composite particles immobilized with metal affinity ions show high potential in the phosphoproteome mass-spectrometric (MS) analysis. However, the preparation of this kind of material still suffers from a complicated synthesis procedure and high cost. In this work, the magnetic nanostructured composite microspheres (MPCS) incorporated into N-methylene phosphonic chitosan were first fabricated via a facile one-pot synthesis strategy and titanium ions (Ti4+) were subsequently immobilized onto the MPCS to form MPCS-Ti4+ affinity particles. The uniform spherical MPCS-Ti4+ affinity particles with abundant chelated titanium ions have a particle size distribution between 126 nm and 280 nm, and they display superparamagnetism with a saturation magnetization (Ms) value of 44.75 emu g-1. The amount of the immobilized Ti4+ ions was estimated to be 11.6 wt% by EDS. The MPCS-Ti4+ exhibited excellent dispersibility in aqueous solution, high affinity selectivity for phosphopeptides and quite fast magnetic separation within 10 s as well as good reusability. Thus, the prepared magnetic MPCS-Ti4+ nanostructured affinity materials will possess great potential in phosphoproteome research.

7.
ACS Appl Mater Interfaces ; 5(8): 3182-90, 2013 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-23514605

RESUMO

The flowerlike multifunctional affinity microspheres prepared by a facile solvothermal synthesis and subsequent calcination process consist of magnetic cores and hierarchical meso-/macroporous TiO2 shells. The hierarchical porous structure of the flowerlike affinity microspheres is constructed by the macroporous shell from the stacked mesoporous nanopetals which are assembled by small crystallites. The affinity microspheres have a relatively large specific surface area of 50.45 m(2) g(-1) and superparamagnetism with a saturation magnetization (Ms) value of 30.1 emu g(-1). We further demonstrate that they can be applied for rapid and effective purification of phosphoproteins, in virtue of their selective affinity, porous structure, and strong magnetism. In addition, the affinity microspheres can also be used for enrichment of phosphopeptides, and the selectivity is greatly improved due to the increase of mass transport and prevention of the possible "shadow effect" resulting from the smaller and deeper pores by taking advantage of the unique porous structure. Overall, this work will be highly beneficial for future applications in the isolation and identification of phosphorylated biomolecules.


Assuntos
Magnetismo/métodos , Fosfopeptídeos/isolamento & purificação , Fosfoproteínas/isolamento & purificação , Adsorção , Magnetismo/instrumentação , Microesferas , Fosfopeptídeos/química , Fosfoproteínas/química , Porosidade
8.
J Mater Chem B ; 1(10): 1491-1500, 2013 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-32260789

RESUMO

The multifunctional microspheres consisting of the magnetic γ-Fe2O3 core and the affinity REVO4 (RE = Sm, Dy, Ho) shell have been synthesized via the homogenous precipitation-calcination-ion exchange three-step synthetic route. Their morphologies, structures, surface properties, and magnetisms were characterized, respectively. SEM and TEM images indicate that they all have an average size of about 400 nm and very rough surfaces. The TEM images further reveal that the γ-Fe2O3@REVO4 microspheres are all core-shell structures and the REVO4 shells are about 55-60 nm in thickness. The XRD pattern analyses show that the magnetic γ-Fe2O3 cores belong to cubic structure and the REVO4 (RE = Sm, Dy, Ho) shells are composed of their corresponding tetragonal major phases. HRTEM images, FTIR spectra and EDS further demonstrate the formations of tetragonal REVO4 shells based on checkup of the corresponding lattice fringes, characteristic IR absorption peaks and element signals. Their potentials for selective capture, rapid separation, and convenient mass spectra (MS) labeling of the phosphopeptides from complex proteolytic digests are explored and evaluated for the first time. The experimental results show that the magnetic γ-Fe2O3@REVO4 core-shell structured microspheres have high selective affinity for the phosphopeptides. The trapped phosphopeptides can be rapidly isolated by an external magnetic field, and can be easily identified by characteristic MS signals from 80 Da mass losses in the mass spectra (MS). Additionally, the γ-Fe2O3@REVO4 affinity materials can be reused after recovery.

9.
J Mater Chem B ; 1(37): 4845-4854, 2013 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-32261166

RESUMO

Novel three-dimensional (3D) flowerlike hierarchical γ-Fe2O3@xNH4F·yLuF3 core-shell architectures were synthesized by a simple phase transformation route under mild conditions. The evolution of the flowerlike structure assembled by thin xNH4F·yLuF3 nanosheets has been investigated in detail. We found that an appropriate amount of NH4F and a suitable phase transformation reaction temperature are crucial for the formation of the flowerlike structure, while the calcination treatment is essential to maintain the well-defined core-shell structure. A possible formation mechanism was proposed for the phase transformation reaction and the self-assembly growth in situ. The novel composite material with large open pores, a specific surface area (26.2 m2 g-1), strong reversible magnetic response (Ms = 27.99 emu g-1), and good structural stability has been primarily applied for the selective and effective capture of phosphopeptides and it showed good performance. The obtained products may also have potential applications in areas such as water treatment, purification of biomolecules, and solid catalysis.

10.
J Mater Chem B ; 1(30): 3661-3669, 2013 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32261263

RESUMO

Architectural design is important to achieve appropriate chemical and biological properties of nanostructures. Yolk-shell magnetic microspheres consisting of Fe3O4 cores and porous and hollow YPO4 affinity shells have been designed and constructed. The yolk-shell magnetic microspheres have a saturation magnetization (Ms) value of 48.3 emu g-1 with a negligible coercivity and remanence at 300 K and a BET specific surface area of 12.5 m2 g-1 with an average pore size of 10.1 nm for the mesoporous YPO4 shell. The novel multifunctional yolk-shell nanostructures can realize the selective capture, convenient magnetic separation and rapid identification of target phosphopeptides by taking advantage of the Fe3O4 magnetic cores and the selective YPO4 affinity shells. Sensitivity and selectivity of the affinity yolk-shell nanostructures were evaluated by digests of standard proteins and complex biosamples. 2678 unique phosphopeptides were captured and identified from the digest of mouse brain proteins. Therefore, this work will be highly beneficial for future applications in the isolation and purification of biomolecules, in particular, low-abundance phosphopeptide biomarkers.

11.
Nanotechnology ; 23(42): 425702, 2012 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-23037970

RESUMO

Magnetic-fluorescent particles with targeting functionalities were fabricated by a modified Stöber method and two shapes (spherical and beanpod-like) were obtained by simply tuning the reaction temperature. The two multifunctional probes combined the useful functions of magnetism, fluorescence and FA (folic acid)-targeting recognition into one entity. The products were characterized by scanning electron microscopy, transmission electron microscopy, photoluminescence spectroscopy, confocal laser scanning microscopy, by a superconducting quantum interference device and by Fourier transform infrared spectroscopy. The experimental results show that the products possessed rapid magnetic response, relatively strong fluorescent signal, higher photostability and FA-targeting recognition as well as good water-dispersibility, suggesting that they would have potential medical applications in biolabeling and bioimaging.


Assuntos
Magnetismo , Nanopartículas/química , Nanotecnologia/métodos , Ácido Fólico/química , Microscopia Confocal , Nanopartículas/ultraestrutura , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier
12.
Chem Commun (Camb) ; 48(82): 10240-2, 2012 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-22968221

RESUMO

A novel multifunctional graphene-based affinity probe has been explored for selective capture of two different types of peptides from the biosamples for sequential detection.


Assuntos
Grafite/química , Sondas Moleculares/química , Peptídeos/sangue , Biomarcadores/sangue , Humanos , Lantânio/química , Sondas Moleculares/síntese química , Óxidos/química , Fosfatos/química
13.
Small ; 8(22): 3456-64, 2012 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-22893533

RESUMO

Novel core-shell structured Fe3O4@LnPO4 (Ln=Eu, Tb, Er) multifunctional microspheres with a magnetic Fe3O4 core and a LnPO4 shell covered with spikes are synthesized for the first time through the combination of a homogeneous precipitation approach and an ion-exchange process. Their potential for selective capture, rapid separation, and easy mass spectrometry (MS) labeling of the phosphopeptides from complex proteolytic digests are evaluated. These affinity microspheres can improve the specificity for capture of the phosphopeptides, realize fast magnetic separation, enhance the MS detection signals, and directly identify phosphopeptides through 80 Da mass loss in the mass spectra. The synthesis strategy could become a general and effective technique for similar core-shell hierarchical structures.


Assuntos
Óxido Ferroso-Férrico/química , Espectrometria de Massas/métodos , Microesferas , Nanotecnologia/métodos , Fosfatos/química , Fosfopeptídeos/química , Érbio/química , Európio/química , Íons , Magnetismo , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Espectroscopia de Infravermelho com Transformada de Fourier , Térbio/química , Difração de Raios X
14.
Anal Bioanal Chem ; 404(3): 763-70, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22722743

RESUMO

Novel Fe(3)O(4)@La(x)Si(y)O(5) affinity microspheres consisting of a superparamagnetic Fe(3)O(4) core and an amorphous lanthanum silicate shell have been synthesized. The core-shell-structured Fe(3)O(4)@La(x)Si(y)O(5) microspheres, with a mean size of ca. 480 nm, had rough lanthanum silicate surfaces and displayed relatively strong magnetism (47.2 emu g(-1)). This novel affinity material can be used for selective capture, rapid magnetic separation, and part dephosphorylation (which plays an important role in identifying phosphopeptides in MS) of the phosphopeptides in a peptide mixture. Its ability to selectively trap and magnetically isolate as well as label the phosphopeptides was evaluated using a standard phosphorylated protein (ß-casein) and a real sample (human serum). Phosphopeptides and their corresponding label ions were detected for concentrations of ß-casein as low as 1 × 10(-9) M and in mixtures of ß-casein and BSA with molar ratios as low as 1:50. In addition, this affinity material, with its labeling properties, is superior to commercial TiO(2) beads in terms of interference from non-phosphopeptide molecules. These results reveal that the lanthanum silicate coated magnetic microspheres represent a promising affinity material for the rapid purification and recognition of phosphopeptides.


Assuntos
Óxido Ferroso-Férrico/química , Lantânio/química , Fosfopeptídeos/isolamento & purificação , Silicatos/química , Animais , Caseínas/análise , Caseínas/química , Bovinos , Humanos , Imãs , Microscopia Eletrônica de Varredura , Microesferas , Tamanho da Partícula , Fosforilação , Soroalbumina Bovina/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Propriedades de Superfície
15.
Chemistry ; 18(7): 2014-20, 2012 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-22241661

RESUMO

Rare-earth phosphate microspheres with unique structures were developed as affinity probes for the selective capture and tagging of phosphopeptides. Prickly REPO(4) (RE = Yb, Gd, Y) monodisperse microspheres, that have hollow structures, low densities, high specific surface areas, and large adsorptive capacities were prepared by an ion-exchange method. The elemental compositions and crystal structures of these affinity probes were confirmed by energy-dispersive spectroscopy (EDS), powder X-ray diffraction (XRD), and Fourier-transform infrared (FTIR) spectroscopy. The morphologies of these compounds were investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and nitrogen-adsorption isotherms. The potential ability of these microspheres for selectively capturing and labeling target biological molecules was evaluated by using protein-digestion analysis and a real sample as well as by comparison with the widely used TiO(2) affinity microspheres. These results show that these porous rare-earth phosphate microspheres are highly promising probes for the rapid purification and recognition of phosphopeptides.


Assuntos
Elementos da Série dos Lantanídeos/química , Microesferas , Fosfopeptídeos/análise , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Modelos Moleculares , Estrutura Molecular , Fosfopeptídeos/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
16.
Chem Commun (Camb) ; 47(20): 5732-4, 2011 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-21503338

RESUMO

Fe(3)O(4)@SiO(2)@CeO(2) microspheres with magnetic core and mesoporous shell were synthesized, and the multifunctional materials were utilized to capture phosphopeptides and catalyze the dephosphorylation simultaneously, thereby labeling the phosphopeptides for rapid identification.


Assuntos
Cério/química , Óxido Ferroso-Férrico/química , Microesferas , Fosfopeptídeos/química , Dióxido de Silício/química , Magnetismo , Porosidade , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
17.
J Nanosci Nanotechnol ; 11(11): 9656-60, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22413265

RESUMO

Fluorescent rare earth complex Eu(DBM)3(phen)]Cl3@SiO2-NH2 nanoparticles were synthesized by combination of solvent precipitation method and Stöber method. The morphologies, structure, surface and optical properties of the samples were characterized by field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), fourier transform infrared (FTIR) spectroscopy, thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), and fluorescence spectrophotometer (FS). The observation from FE-SEM images indicate that the obtained samples are spherical and uniform nanoparticles with a tunable average sizes from 140 nm to 300 nm. TEM results verify a core-shell structure of the nanoparticles. The FTIR spectrum confirms the characteristic vibration absorption peaks of the complex [Eu(DBM)3(phen)]Cl3@SiO2-NH2. TGA result indicates that the complex is stable below 200 degrees C. The photoluminescence analysis shows that the complex has Eu3+ characteristic red luminescence and broader excitation peak from 200 nm to 450 nm that can meet the demands of fluorescent confocal imaging. The amino groups are directly introduced to the [Eu(DBM)3(phen)]Cl3@SiO2-NH2 nanoparticles surface by using APS (3-aminopropyl triethoxysilane). This makes the surface modification and bioconjugation of the nanoparticles easier. The nano-sized spheres could be provided a basis for further expansion of its application in biomedical imaging, biological detection and fluorescent nanoprobes.


Assuntos
Corantes Fluorescentes/química , Nanocompostos/química , Nanopartículas/química , Compostos Organometálicos/química , Fenantrolinas/química , Dióxido de Silício/química , Corantes Fluorescentes/síntese química , Microscopia Eletrônica , Tamanho da Partícula
18.
J Nanosci Nanotechnol ; 11(11): 9774-9, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22413292

RESUMO

In this paper, we describe the synthesis and characterization of a luminomagnetic microspheres with core-shell structures (denoted as Fe3O4@ SiO2 @SiO2-Tb(PABA)3). The luminomagnetic microspheres were characterized by field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), vibrating sample magnetometer (VSM), and photoluminescence spectrophotometer (PL). The SEM observation shows that the microsphere consists of the magnetic core with about 400 nm in average diameter and silica shell doped with terbium complex with an average thickness of about 90 nm. It has a saturation magnetization of 15.8 emu/g and a negligible coercivity at room temperature and exhibits strong green emission peak from 5D4 --> 7F5 transition of Tb3+ ions. The luminomagnetic microspheres with good magnetic response and fluorescence probe property as well as water-dispersibility would have potential medical applications, such as time-resolved fluoroimmunoassay (TR-FIA), fluorescent imaging, and magnetic resonance imaging (MRI).


Assuntos
Ácido 4-Aminobenzoico/química , Óxido Ferroso-Férrico/química , Microesferas , Dióxido de Silício/química , Térbio/química , Corantes Fluorescentes/química , Magnetismo , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier
19.
Talanta ; 82(2): 450-7, 2010 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-20602919

RESUMO

The core-shell structured luminomagnetic microsphere composed of a Fe(3)O(4) magnetic core and a continuous SiO(2) nanoshell doped with Eu(DBM)(3).2H(2)O fluorescent molecules was fabricated by a modified Stöber method combined with a layer-by-layer assembly technique. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), confocal microscopy, photoluminescence (PL), and superconducting quantum interface device (SQUID) were employed to characterize the Fe(3)O(4)@SiO(2)@Eu(DBM)(3).2H(2)O/SiO(2) microspheres. The experimental results show that the microshpere has a typical diameter of ca. 500 nm consisting of the magnetic core with about 340 nm in diameter and silica shell doped with europium complex with an average thickness of about 80 nm. It possesses magnetism with a saturation magnetization of 25.84 emu/g and negligible coercivity and remanence at room temperature and exhibits strong red emission peak originating from electric-dipole transition (5)D(0)-->(7)F(2) (611 nm) of Eu(3+) ions. The luminomagnetic microspheres can be uptaken by HeLa cells and there is no adverse cell reaction. These results suggest that the luminomagnetic microspheres with magnetic resonance response and fluorescence probe property may be useful in biomedical imaging and diagnostic applications.


Assuntos
Óxido Ferroso-Férrico/química , Microesferas , Imagem Molecular , Compostos Organometálicos/química , Dióxido de Silício/química , Óxido Ferroso-Férrico/síntese química , Células HeLa , Humanos , Luminescência , Magnetismo , Microscopia Eletrônica de Transmissão , Compostos Organometálicos/síntese química , Dióxido de Silício/síntese química , Água/química , Difração de Raios X
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