Gold nanoshells with magnetic cores and a urea-based receptor for SERS sensing of fluoride anions: experimental and computational study.

The study demonstrates that a combination of plasmonic nanostructures and artificial receptors can be applied for sensing small molecular species. Gold nanoshells containing magnetic cores are used as the SERS-active substrates, which opens the way for the development of multimodal contrast agents with applicability extended to sensing or for the separation of analytes by magnetic solid-phase extraction. Disubstituted ureas forming hydrogen-bonded complexes with certain anions can be employed as molecular sensors.

Multimodal Contrast Agent Enabling pH Sensing Based on Organically Functionalized Gold Nanoshells with Mn-Zn Ferrite Cores.

Highly complex nanoparticles combining multimodal imaging with the sensing of physical properties in biological systems can considerably enhance biomedical research, but reports demonstrating the performance of a single nanosized probe in several imaging modalities and its sensing potential at the same time are rather scarce. Gold nanoshells with magnetic cores and complex organic functionalization may offer an efficient multimodal platform for magnetic resonance imaging (MRI), photoacoustic imaging (PAI), and fluorescence techniques combined with pH sensing by means of surface-enhanced Raman spectroscopy (SERS). In the present study, the synthesis of gold nanoshells with Mn-Zn ferrite cores is described, and their structure, composition, and fundamental properties are analyzed by powder X-ray diffraction, X-ray fluorescence spectroscopy, transmission electron microscopy, magnetic measurements, and UV-Vis spectroscopy.

Multimodal fluorescently labeled polymer-coated GdF nanoparticles inhibit degranulation in mast cells.

Multimodal gadolinium fluoride nanoparticles belong to potential contrast agents useful for bimodal optical fluorescence and magnetic resonance imaging. However, the metallic nature of the nanoparticles, similarly to some paramagnetic iron oxides, might induce allergic and anaphylactic reactions in patients after administration. A reduction of these adverse side effects is a priority for the safe application of the nanoparticles.

Modelling and Measurement of Magnetically Soft Nanowire Arrays for Sensor Applications.

Soft magnetic wires and microwires are currently used for the cores of magnetic sensors. Due to their low demagnetization, they contribute to the high sensitivity and the high spatial resolution of fluxgates, Giant Magnetoimpedance (GMI), and inductive sensors. The arrays of nanowires can be prepared by electrodeposition into predefined pores of a nanoporous polycarbonate membrane.

Spatial covariance of herbivorous and predatory guilds of forest canopy arthropods along a latitudinal gradient.

In arthropod community ecology, species richness studies tend to be prioritised over those investigating patterns of abundance. Consequently, the biotic and abiotic drivers of arboreal arthropod abundance are still relatively poorly known. In this cross-continental study, we employ a theoretical framework in order to examine patterns of covariance among herbivorous and predatory arthropod guilds.

Broadband dielectric spectroscopy of LaSrMnO@TiOcore-shell nanocomposites.

Core-shell composites of ferromagnetic conducting nanoparticles LaSrMnO(LSMO) embedded in an insulating matrix of TiO(LSMO@TiO) have been processed, structurally and magnetically characterized, and their DC magnetoresistivity and complex dielectric response measured and fitted from Hz up to the infrared (IR) range (10Hz). XRD indicates that the TiOshells are amorphous. Modelling of the IR spectra using standard models based on the effective medium approximation has it confirmed and has characterized the effective phonon modes of the LSMO nanoceramics and LSMO@TiOcomposite.

Magnetic nanoparticles of Ga-substituted ε-Fe O for biomedical applications: Magnetic properties, transverse relaxivity, and effects of silica-coated particles on cytoskeletal networks.

Magnetic nanoparticles of ε-Fe Ga O with the volume-weighted mean size of 17 nm were prepared by thermal treatment of a mesoporous silica template impregnated with metal nitrates and were coated with silica shell of four different thicknesses in the range 6-24 nm. The bare particles exhibited higher magnetization than the undoped compound, 22.4 Am kg at 300 K, and were characterized by blocked state with the coercivity of 1.

Multimodal PSSMA-Functionalized GdF : Eu (Tb ) Nanoparticles for Luminescence Imaging, MRI, and X-Ray Computed Tomography.

Biocompatible poly(4-styrenesulfonic acid-co-maleic acid)-stabilized GdF  : Eu (Tb ) nanoparticles were obtained by a one-step coprecipitation method in ethylene glycol or water. The particles are very small (3 nm), have a narrow size distribution, and were detectable by fluorescence, magnetic resonance, and X-ray contrast imaging. These properties allow multimodal imaging, which has prospective applications in the simultaneous and detailed detection of diseased tissues.

Synthesis and characterization of Au nanoshells with a magnetic core and betaine derivatives.

The article describes preparation, characterization and further modification of hybrid magnetic particles (Au nanoshells with a magnetic core (MPs@silica@Au)) by zwitterionic molecules bearing diazonium functional groups. Such hybrid magnetic particles modified by zwitterionic molecules exhibit the following features: •Responsiveness towards external magnetic field applicable for various enrichment strategies due to magnetic core;•Golden outer layer exhibiting free surface plasmons could be used for grafting of zwitterionic molecules diazonium functionality;•Zwitterionic interface on such particles provides resistivity towards non-specific protein binding; and at the same time such interface was applied for immobilization of antibodies against prostate specific antigen (PSA) applied for selective enrichment of PSA from serum samples with subsequent electrochemical assays. The approach presented here using hybrid magnetic particles can be easily applied for immobilization of antibodies using a highly robust surface patterning protocols by formation of a self-assembled monolayer with delivery of functional groups on the outer surface of magnetic particles.

Quantitative assessment of plant-arthropod interactions in forest canopies: A plot-based approach.

Research on canopy arthropods has progressed from species inventories to the study of their interactions and networks, enhancing our understanding of how hyper-diverse communities are maintained. Previous studies often focused on sampling individual tree species, individual trees or their parts. We argue that such selective sampling is not ideal when analyzing interaction network structure, and may lead to erroneous conclusions.

Advanced impedimetric biosensor configuration and assay protocol for glycoprofiling of a prostate oncomarker using Au nanoshells with a magnetic core.

In this paper several advances were implemented for glycoprofiling of prostate specific antigen (PSA), what can be applied for better prostate cancer (PCa) diagnostics in the future: 1) application of Au nanoshells with a magnetic core (MP@silica@Au); 2) use of surface plasmons of Au nanoshells with a magnetic core for spontaneous immobilization of zwitterionic molecules via diazonium salt grafting; 3) a double anti-fouling strategy with integration of zwitterionic molecules on Au surface and on MP@silica@Au particles was implemented to resist non-specific protein binding; 4) application of anti-PSA antibody modified Au nanoshells with a magnetic core for enrichment of PSA from a complex matrix of a human serum; 5) direct incubation of anti-PSA modified MP@silica@Au with affinity bound PSA to the lectin modified electrode surface. The electrochemical impedance spectroscopy (EIS) signal was enhanced 43 times integrating Au nanoshells with a magnetic core compared to the biosensor without them. This proof-of-concept study shows that the biosensor could detect PSA down to 1.

Manganese-Zinc Ferrites: Safe and Efficient Nanolabels for Cell Imaging and Tracking In Vivo.

Manganese-zinc ferrite nanoparticles were synthesized by using a hydrothermal treatment, coated with silica, and then tested as efficient cellular labels for cell tracking, using magnetic resonance imaging (MRI) in vivo. A toxicity study was performed on rat mesenchymal stem cells and C6 glioblastoma cells. Adverse effects on viability and cell proliferation were observed at the highest concentration (0.

Phylogenetic composition of host plant communities drives plant-herbivore food web structure.

Insects tend to feed on related hosts. The phylogenetic composition of host plant communities thus plays a prominent role in determining insect specialization, food web structure, and diversity. Previous studies showed a high preference of insect herbivores for congeneric and confamilial hosts suggesting that some levels of host plant relationships may play more prominent role that others.

Magnetic properties of rare-earth-doped LaSrMnO.

Rare-earth-doped ferromagnetic manganites LaRESrMnO (RE  =  Gd, Tb, Dy, and Ho) are synthesized in the form of sintered ceramics and nanocrystalline phases with the mean size of crystallites  ≈30 nm. The electronic states of the dopants are investigated by SQUID magnetometry and theoretically interpreted based on the calculations of the crystal field splitting of rare-earth energy levels. The samples show the orthorhombic perovskite structure of Ibmm symmetry, with a complete FM order of Mn spins in bulk and reduced order in nanoparticles.

Effects of Tb(3+) dopants in the La1-x Sr x MnO3 bulk and nanoparticle ferromagnets.

Three forms of La,Sr-manganites are synthesized and the role of Tb doping is investigated. First two systems are sol-gel nanoparticles and sintered ceramics of the composition La0.56Tb0.

Fluorescent magnetic nanoparticles for cell labeling: flux synthesis of manganite particles and novel functionalization of silica shell.

Novel synthetic approaches for the development of multimodal imaging agents with high chemical stability are demonstrated. The magnetic cores are based on La0.63Sr0.

The global distribution of diet breadth in insect herbivores.

Understanding variation in resource specialization is important for progress on issues that include coevolution, community assembly, ecosystem processes, and the latitudinal gradient of species richness. Herbivorous insects are useful models for studying resource specialization, and the interaction between plants and herbivorous insects is one of the most common and consequential ecological associations on the planet. However, uncertainty persists regarding fundamental features of herbivore diet breadth, including its relationship to latitude and plant species richness.

Gadolinium- and manganite-based contrast agents with fluorescent probes for both magnetic resonance and fluorescence imaging of pancreatic islets: a comparative study.

Three magnetic resonance (MR)/fluorescence imaging probes were tested for visualization, cellular distribution, and survival of labeled pancreatic islets in vitro and following transplantation. As T(1) contrast agents (CAs), gadolinium(III) complexes linked to β-cyclodextrin (Gd-F-βCD) or bound to titanium dioxide (TiO2 @RhdGd) were tested. As a T(2) CA, perovskite manganite nanoparticles (LSMO@siF@si) were examined.

Anilinium dihydrogen phosphate.

The triclinic structure of the title compound, C(6)H(8)N(+)·H(2)PO(4)(-), with three symmetry-independent structural units (Z' = 3), is formed of separate organic and inorganic layers alternating along the b axis. The building blocks of the inorganic layer are deformed H(2)PO(4) tetrahedra assembled into infinite ladders by short and hence strong hydrogen bonds. The anilinium cations forming the organic layer are not hydrogen bonded to one another, but they are anchored by four N-H···O crosslinks between the dihydrogen phosphate chains of adjacent ladders.

Silica-coated La0.75Sr0.25MnO3 nanoparticles for magnetically driven DNA isolation.

Magnetic La(0.75)Sr(0.25)MnO(3) nanoparticles possessing an approximately 20-nm-thick silica shell (LSMO(0.