Trapping of cells is essential to perform basic handling operations in cell-based microsystems, such as media exchange, concentration, cell isolation and cell sorting. Cell trapping by magnetophoresis typically requires cell labeling with magnetic nanoparticles. Here we report on endocytotic uptake of 100 nm magnetic nanoparticles by Human Embryonic Kidney 293 cells. The attraction of labeled c...

We study magnetic-field directed self-assembly of magnetic nanoparticles onto templates recorded on perpendicular magnetic recording media, and quantify feature width and height as a function of assembly time. Feature widths are determined from Scanning Electron Microscope (SEM) images, while heights are obtained with Atomic Force Microscopy (AFM). For short assembly times, widths were ~150 nm,...

The formation of magnetic bead or nanoparticle superstructures due to magnetic dipole dipole interactions can be used as configurable matter in order to realize low-cost magnetoresistive sensors with very high GMR-effect amplitudes. Experimentally, this can be realized by immersing magnetic beads or nanoparticles in conductive liquid gels and rearranging them by applying suitable external magne...

in this study, we synthesized herceptin conjugated magnetic nanoparticles (hmns) as an alternative probe to discover the levels of her2 (human epidermal growth factor receptor-2) in the surface of cells. these nanoparticles can be used by magnetic resonance imaging (mri) (non-invasive methods) for screening the patients with her2 positive or negative tumors. dextran coated iron oxide nanopartic...

This chapter provides an introduction to the fundamental physical ideas and models relevant to the phenomenon of magnetic hysteresis in nanoparticle assemblies. The concepts of single-domain particles and superparamagnetism are discussed. The mechanisms of magnetization by coherent rotation and the role of temperature in the gradual decay of magnetization are analyzed in the framework of simple...

This theme issue provides a timely collection of studies on magnetic nanoparticle-based imaging, bio-sensing, therapy and/or their combinations.

Many types of biosensors employ magnetic nanoparticles (diameter = 5-300 nm) or magnetic particles (diameter = 300-5,000 nm) which have been surface functionalized to recognize specific molecular targets. Here we cover three types of biosensors that employ different biosensing principles, magnetic materials, and instrumentation. The first type consists of magnetic relaxation switch assay-sensor...

Magnetic γ-Fe(2)O(3) nanoparticles with a mean diameter of 20 nm and size distribution of 7% were chemically synthesized and spin-coated on top of a Si-substrate. As a result, the particles self-assembled into a monolayer with hexagonal close-packed order. Subsequently, the nanoparticle array was coated with a Co layer of 20 nm thickness. The magnetic properties of this composite nanoparticle/t...

the discharge of lead containing effluents into the environment and water bodies is harmful for the human, animals, aquatic flora and fauna. herein, a novel surface engineered magnetic nanoparticle for removing pb2+ ions was studied. after surface modification of the magnetite by 3-amino-propyltriethoxysilane (aptes) magnetic nanoparticles with covalently linked porphyrins were synthesized. two...