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A redox-transmetalation process that is effective as a general protocol for the fabrication of high quality and well-defined core-shell type bimetallic nanoparticles on the sub-10 nm scale is presented. The nanostructures, magnetic properties and reaction byproducts of the core-shell nanomaterial including Co@Au, Co@Pd, Co@Pt and nanoparticles are spectroscopically characterized and identified to confirm the chemical process that promotes the core-shell structure formation.

Research has been conducted on the copper deposits and their photochemical synthesis. The use of luminescence and mass spectroscopy are described.

Research has been conducted on the charge transfer transitions in metal complexes. The effect of the metal on the ligand to ligand charge transfer is examined.

The article explains a newly devised core-shell design concept, which can be used for the fabrication of the dual mode nanoparticle contrast agents (DMCAs). These agents are shown to be extremely beneficial for the enhancement of the accuracy of MR imaging.

A novel material that has incorporated zinc-doped iron oxide nanocrystals within a mesoporous silica framework that is surface-modified with pseudorotaxanes is described. This material is shown to be a noninvasive, externally controlled drug delivery system with cancer-killing properties.

The article discusses the significance of the nanoscaling laws of magnetic nanoparticles in studying the behavior of existing materials and for being used in the field of biomedical sciences. These laws are found to be extremely useful for optimizing the magnetic properties of the nanoparticles, hence increasing their applicabilities.

The development of heterodimer nanoparticles of FePt-Au with multifunctionalities is described. The catalytic effects of FePt for heteroepitaxial Au growth, high water-solubility and biocompatibility attained through versatile ligand chemistry of Au-S linkages, Au for chip-based biosensing and magnetic resonance (MR) contrast effects of superparamagnetic FePt are determined.

The progress on the synthetic development of symmetry-controlled colloidal nanocrystals of semiconductor and metal oxide prepared through nonhydrolytic chemical routes is reported. The shape of the nanocrystal was determined with the help of the crystalline phase of nucleating seeds, surface energy, kinetic vs thermodynamic growth and selective adhesion processes of capping ligands.

A surface-modulated and highly biocompatible magnetic iron oxide nanocrystal probe that could be used for efficient intracellular labeling and their magnetic resonance imaging applications is presented. The preparation of these probes and the results from studies exploring their transport into various cell types and magnetic resonance contrast effect, cytotoxicity, and application in vivo monitoring of neural stem cell migration in rat spinal cord is described.

An easy and reliable method for the production of patterned monolayers of Co nanoparticles is described. A two-dimensional monolayer of Co nanoparticles is fabricated by spreading a nanoparticle solution over an air-water interface and then transferring it to a hydrophobic substrate by using the Langmuir-Blodgett (LB) method.

A report is presented on the development of a synthetically controlled magnetic nanocrystal model system that correlates the nanoscale tunabilities in terms of size, magnetism, and an induced nuclear spin relaxation processes. The magnetic model system further leads to the development of high-performance magnetic nanocrytsal probe systems for diagnosis of breast cancer lines.

A general and highly effective one-pot synthetic protocol to produce 1-dimensional nanostructures of transition metal oxide through thermally induced crystal growth processes from a mixture of metal chloride and surfactants are presented. The general applicability of the synthetic protocol was tested to V(sub 2)O(sub 5) nanocrystals was tested where 1-D shaped nanocrystals could also be obtained.

The shape evolutions of magnetic iron oxide nanocrystals utilizing a simple one-step synthesis without any additional reagents such as (CH3)(sub 3)NO are reported. These types of studies concerning the shape evolution of nanocrystals should be valuable for further design and for greater understanding of advanced nanoscale building-block architectures.

It is demonstrated that a series of shape evolutions ranging from anisotropic to isotropic forms is possible even in highly symmetric rock-salt phased semiconductors. The initial injection of molecular precursor into hot solvent immediately results in the formation of truncated octahedron-shaped nuclei terminated by two characteristic faces: {100} faces with high surface energy and {111} faces with low surface energy in the presence of strong adsorbent.

The magnetic semicontrolled nanocrystals, which are shape and dopant controlled, have been achieved by the thermolysis of nonpyrophoric and less reactive single molecular precursors under a monosurfactant system. Reaction parameters governing both the intrinsic crystalline phase and the growth regime are important for the synthesis of various shapes of MnS nanocrystals that include cubes, spheres, 1-dimensional (1-D) monowires, and branched wires (bipods, tripods, and tetrapods).

A route for shape and crystalline phase control of GaP (gallium phosphide) nanocrystals is successfully developed using a single molecular precursor approach. The first liquid phase syntheses of anisotropic III-V semiconductor within a quantum-confined region with a width of less than 10 nm.

Developing innovative tools that facilitate the understanding of sophisticated biological systems has been one of the Holy Grails in the physical and biological sciences. In this Commentary, we discuss recent advances, opportunities, and challenges in the use of nanomaterials as a precision tool for biology and medicine. [ABSTRACT FROM AUTHOR]

Investigates the synthesis of 'solid solution' and 'core-shell' types of well-defined cobalt-platinum nanoalloys. Influence of redox transmetalation reactions on the alloy formation; Magnetic and structural properties of the obtained nanoparticles; Analysis on the byproduct reactions obtained from the reaction mixtures.

Examines the gas phase photoproduction of diatomic metal nitrides during metal nitride laser chemical vapor deposition. Photofragmentation reactions that lead to deposition under two gas-phase conditions; Deposition of films; Molecular collisions; Photochemistry of the films to intramolecular reactions.

We demonstrate a novel magnetophoretic immunoassay of allergen-specific immunoglobulin E (IgE) based on the magnetophoretic deflection velocity of a microbead that is proportional to the associated magnetic nanoparticles under enhanced magnetic field gradient in a microchannel. In this detection scheme, two types of house dust mites, Dermatophagoides farinae (D. farinae) and Dermatophagoides pteronyssinus (D. pteronyssinus), were used as the model allergens. Polystyrene microbeads were conjugated with each of the mite extracts followed by incubation with serum samples. The resulting mixture was then reacted with magnetic nanoparticle-conjugated anti-human IgE for detection of allergen-specific IgE by using sandwich immuno-reactions. A ferromagnetic microstructure combined with a permanent magnet was employed to increase the magnetic field gradient (∼104 T/m) in a microfluidic device. The magnetophoretic velocities of microbeads were measured in a microchannel under applied magnetic field, and the averaged velocity was well correlated with the concentration of allergen-specific IgE in serum. From the analysis of pooled sera obtained from 44 patients, the detection limits of the allergen-specific human IgEs for D. farinae and D. pteronyssinus were determined to be 565 (0.045 IU/mL) and 268 fM (0.021 IU/mL), respectively. These values are 1 order of magnitude lower than those by a conventional CAP system. For evaluation of reproducibility and accuracy, unknown sera were subjected to a blind test by using the developed assay system, and they were compared with the CAP system. As a result, coefficient of variance was less than 10%, and the developed method enabled a fast assay with a tiny amount of serum (∼10 μL). [ABSTRACT FROM AUTHOR]

The structure, magnetism, and phase transition of core-shell type CoPt nanoparticles en route to solid solution alloy nanostructures are systematically investigated. The characterization of COcorePtshell nanoparticles obtained by a "redox transmetalation" process by transmission electron microscopy (TEM) and, in particular, X-ray absorption spectroscopy (XAS) provides clear evidence for the existence of a core-shell type bimetallic interlacial structure. Nanoscale phase transitions of the COcorePtshell structures toward c-axis compressed face-centered tetragonal (fct) solid solution alloy CoPt nanoparticles are monitored at various stages of a thermally induced annealing process and the obtained fct nanoalloys show a large enhancement of their magnetic properties with ferromagnetism. The relationship between the nanostructures and their magnetic properties is in part elucidated through the use of XAS as a critical analytical tool. [ABSTRACT FROM AUTHOR]

Examines the surfactant driven shape-controlled synthesis of gallium phosphide semiconductor nanocrystals. Thermal decomposition of molecular precursor; Crystal shape; Crystal growth.