Zero-velocity Magnetophoretic Method for the Determination of Particle Magnetic Susceptibility

Abstract

A simple zero-velocity method to determine the particle magnetic susceptibility by measuring the magnetophoretic velocity was proposed. The principle is that the magnetophoretic velocity of a particle in a liquid medium must be zero when the magnetic susceptibilities of the medium and the particle are equal, or the gravity force and the magnetophoretic force are balanced. By changing the medium magnetic susceptibility and measuring the magnetophoretic velocity of a particle, the particle magnetic susceptibility was determined from the medium magnetic susceptibility under the zero-velocity condition. The feasibility of the method was demonstrated for polystyrene particles using a Dy(III) solution in the horizontal migration mode and different organic solvents in the vertical migration mode.

Magnetic-Field-Induced Painting-Out of Precipitation Bands of Mn–Fe-Based Prussian Blue Analogues in Water–Glass Gels

“…25−27 Magnetophoresis has also been applied to evaluate the magnetic susceptibility of several types of particles, including magnetic particles, 28 ion-labeled biological particles, 28 and polystyrene particles in paramagnetic solvents. 29 In these analytical magnetophoresis studies, the magnetic-field-induced effect has been assumed to be as follows. When the magnetic forces act perpendicular to the flow axis to drive magnetically susceptible particles toward the interpolar gap(s) (this is applicable in our case; see Figure 8), those particles with a high magnetic susceptibility, such as those including a predominance of [Mn(H 2 O) 6 ] 2+ ions, are attracted by the magnetic forces and are easily deposited on the zone in the interpolar gap.…”

“…Magnetic fields have already been used as the one of the external force fields for selectively separating colloidal particles from liquids (see Figure ). − Magnetophoresis has also been applied to evaluate the magnetic susceptibility of several types of particles, including magnetic particles, ion-labeled biological particles, and polystyrene particles in paramagnetic solvents . In these analytical magnetophoresis studies, the magnetic-field-induced effect has been assumed to be as follows.…”

Magnetophoretic Sprinting: A Study on the Magnetic Properties of Aqueous Lanthanide Solutions

“…Among the most relevant studies, a magnetic levitation (MagLev) system allowing high-precision density measurements of diamagnetic materials in paramagnetic liquids, was developed by Whitesides et al 7 The response of paramagnetic liquids to a magnetic field was also used in a zero-velocity method for the estimation of the magnetic susceptibility of particles. 8 Furthermore, a series of dysprosium-based ionic liquids were shown to exhibit strong mobility in the presence of a permanent magnet. 9 The magnetic susceptibility of a chemical compound, the extent of magnetization in response to an external magnetic field, is a physical property that is easily measured and directly related to the electronic configuration.…”

“…Mechanical responses of concentrated lanthanide solutions to magnetic fields have not been investigated as much. Among the most relevant studies, a magnetic levitation (MagLev) system allowing high-precision density measurements of diamagnetic materials in paramagnetic liquids, was developed by Whitesides et al The response of paramagnetic liquids to a magnetic field was also used in a zero-velocity method for the estimation of the magnetic susceptibility of particles . Furthermore, a series of dysprosium-based ionic liquids were shown to exhibit strong mobility in the presence of a permanent magnet …”

Zeptomole Detection Scheme Based on Levitation Coordinate Measurements of a Single Microparticle in a Coupled Acoustic-Gravitational Field

“…Additionally, information on the reaction dynamics and thermodynamics can be deduced from the particle behavior in a physical field. Suwa and Watarai studied the magnetophoresis of various particles − and evaluated the interfacial adsorption of laurate complexes with dysprosium ions on fluorotoluene microdroplets from their magnetophoretic velocities . The surface complexation between laurate and the paramagnetic dysprosium ion largely modifies the magnetic property of the microdroplet and allows detection of the reaction that occurs on the droplet.…”