Related Experiment Video
Updated: Feb 12, 2026

Cell Labeling and Targeting with Superparamagnetic Iron Oxide Nanoparticles
Published on: October 19, 2015
Magnetically tunable liquid dielectric with giant dielectric permittivity based on core-shell superparamagnetic iron
S Vinayasree1,2, T S Nitha1,3, C S Tiwary4,5
1Department of Physics, Cochin University of Science and Technology, Kochi 682022, India.
None:
A liquid dielectric based on a core-shell architecture having a superparamagnetic iron oxide core and a shell of silicon dioxide was synthesized. The frequency dependence of dielectric properties was evaluated for different concentrations of iron oxide. The dependence of magnetic field on the dielectric properties was also studied. Aqueous ferrofluid exhibited a giant dielectric constant of 6.4 × 105 at 0.1 MHz at a concentration of 0.2 vol% and the loss tangent was 3. The large rise in dielectric constant at room temperature is modelled and explained using percolation theory and Maxwell-Wagner-Sillars type polarization. The ferrofluid is presumed to consist of nanocapacitor networks which are wired in series along the lateral direction and parallel along longitudinal direction. On the application of an external magnetic field, the chain formation and its alignment results in the variation of dielectric permittivity.
Related Concept Videos
Susceptibility, Permittivity and Dielectric Constant
Capacitor With A Dielectric
Dielectrics are non-conducting materials with no free or loosely bound electrons. When a dielectric is...
Gauss's Law in Dielectrics
Dielectric Polarization in a Capacitor
Electrostatic Boundary Conditions in Dielectrics
Consider a case where both the mediums across a boundary are two different dielectric materials. Recall that the electric field and electric displacement are proportional and related through the material's permittivity....
The Nucleosome Core Particle
The paradox
Nucleosomes, paradoxically, perform two opposite functions simultaneously. On the one hand, their main responsibility is to protect the delicate DNA strands from physical damage and help achieve a higher compaction ratio. While on the other hand, they must allow polymerase enzymes to access DNA...

