We report a new NMR relaxation time-based method for sensitive and selective dopamine detection using paramagnetic nanoparticles. The Fe(3+) species in the nanoparticles serves as both the contrast agent and the target recognition element. The results demonstrate that paramagnetic nanoparticles, similar to the more widely used superparamagnetic nanoparticles, can be integrated into relaxation b...

Ellipsoid-shaped nanoclusters composed of single superparamagnetic nanoparticles can be generated by emulsion electrospinning. Stretching and subsequent solvent evaporation of iron oxide loaded emulsion droplets during the emulsion electrospinning process enables the creation of such structures embedded in polymer nanofibers. Dissolution of the polymer fibers yields an aqueous dispersion of the...

Magnetic recording currently is the major data storage technology. Conventional magnetic media implement continuous magnetic layers consisting of microscopic grains. Such media have constraints of thermal instability due to the superparamagnetic effect, which occurs when the magnetic grains become too small. The superparamagnetic effect may set the fundamental limit of about 0.5Tbit/inon achiev...

Studies of the magnetization of Fe2O3@Pt nanoparticles at room temperature showed that there is superparamagnetic contribution with high saturation magnetization about 12.35(emu/g), and soft ferromagnetic contribution with narrow coercive field about 58(Oe). In this paper we fitted the hystersis loop of sample with Brillouin function that demonstrating existence of superparamagnetic phase. Tota...

Despite several excellent advantages of MRI as a clinical imaging technique, its application in molecular imaging of cancer has been limited due to the poor sensitivity. Superparamagnetic nanoparticles have received considerable attention as molecular imaging probes with substantially higher molar relaxivities over small molecular T1 agents. Several new imaging methods have been developed to en...

The CoFe2O4 nanoparticles have been synthesized by using a stable ferric salt of FeCl3 with a micellar microemulsion method. The normal micelles are formed by sodium dodecyl sulfate (NaDS) in aqueous solutions. The mean size of the nanoparticles can be controlled from less than 4 nm to about 10 nm through controlling the concentrations of the reagents. The neutron diffraction in combination wit...

The siRNA transfection efficiency of nanoparticles (NPs), composed of a superparamagnetic iron oxide core modified with polycationic polymers (poly(hexamethylene biguanide) or branched polyethyleneimine), were studied in CHO-K1 and HeLa cell lines. Both NPs demonstrated to be good siRNA transfection vehicles, but unmodified branched polyethyleneimine (25 kD) was superior on both cell lines. How...