Investigation of the magnetic susceptibility properties of fresh and fixed mouse heart, liver, skeletal muscle and brain tissue

Klohs, Jan; Hirt, Ann M.

doi:10.1016/j.ejmp.2021.06.014

Cited by 7 publications

(5 citation statements)

References 76 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To compare the magnetic susceptibilities of MagR to the known volume magnetic susceptibilities of typical tissues ( Klohs & Hirt, 2021 ), we converted mass magnetic susceptibilities in CGS units of MagR to volume magnetic susceptibilities ( Figure 5C , D). The volume magnetic susceptibilities of robin MagR and pigeon MagR were –1.4204×10 -6 and –1.2808×10 -6 , respectively, at 300 K, which are more paramagnetic than those of heart and brain tissues (–1.932×10 -5 and –6.928×10 -6 , respectively).…”

Section: Resultsmentioning

confidence: 99%

Unexpected divergence in magnetoreceptor MagR from robin and pigeon linked to two sequence variations

Wang,

Zhang,

Fei

et al. 2024

Zoological Research

View full text Add to dashboard Cite

Birds exhibit extraordinary mobility and remarkable navigational skills, obtaining guidance cues from the Earth’s magnetic field for orientation and long-distance movement. Bird species also show tremendous diversity in navigation strategies, with considerable differences even within the same taxa and among individuals from the same population. The highly conserved iron and iron-sulfur cluster binding magnetoreceptor (MagR) protein is suggested to enable animals, including birds, to detect the geomagnetic field and navigate accordingly. Notably, MagR is also implicated in other functions, such as electron transfer and biogenesis of iron-sulfur clusters, raising the question of whether variability exists in its biochemical and biophysical features among species, particularly birds. In the current study, we conducted a comparative analysis of MagR from two different bird species, including the migratory European robin ( Erithacus rubecula ) and the homing pigeon ( Columba livia ) . Sequence alignment revealed an extremely high degree of similarity between the MagRs of these species, with only three sequence variations. Nevertheless, two of these variations underpinned significant differences in metal binding capacity, oligomeric state, and magnetic properties. These findings offer compelling evidence for the marked differences in MagR between the two avian species, potentially explaining how a highly conserved protein can mediate such diverse functions.

show abstract

Section: Resultsmentioning

confidence: 99%

Unexpected divergence in magnetoreceptor MagR from robin and pigeon linked to two sequence variations

Wang,

Zhang,

Fei

et al. 2024

Zoological Research

View full text Add to dashboard Cite

show abstract

“…In addition, most biological tissues are typically regarded as diamagnetic. For instance, human tissue is weakly diamagnetic with a small volume (static) magnetic susceptibility of the order of

(SI units), which allows the magnetic field to penetrate into it ( 87 , 88 ). However, the magnetic susceptibility of a tissue can vary depending on the frequency range of the applied magnetic field ( 89 ).…”

Section: Methodsmentioning

confidence: 99%

Non-Stokesian dynamics of magnetic helical nanoswimmers under confinement

Fazeli,

Thakore,

Ala-Nissila

et al. 2024

PNAS Nexus

View full text Add to dashboard Cite

Electromagnetically propelled helical nanoswimmers offer great potential for nanorobotic applications. Here, the effect of confinement on their propulsion is characterized using lattice-Boltzmann simulations. Two principal mechanisms give rise to their forward motion under confinement: 1) pure swimming, and 2) the thrust created by the differential pressure due to confinement. Under strong confinement, they face greater rotational drag, but display a faster propulsion for fixed driving frequency in agreement with experimental findings. This is due to the increased differential pressure created by the boundary walls when they are sufficiently close to each other and the particle. Two new analytical relations are presented: 1) for predicting the swimming speed of an unconfined particle as a function of its angular speed and geometrical properties, and 2) an empirical expression to accurately predict the propulsion speed of a confined swimmer as a function of the degree of confinement and its unconfined swimming speed. At low driving frequencies and degrees of confinement, the systems retain the expected linear behavior consistent with the predictions of the Stokes equation. However, as the driving frequency and/or the degree of confinement increase, their impact on propulsion leads to increasing deviations from the Stokesian regime and emergence of nonlinear behavior.

show abstract

“…Here, µ r describes the relative permeability of a medium. For example, for blood and air, µ r is approximately 1 [65]. Aside from the magnetic field, the blood flow and properties of SPIONs also play an essential role in the performance of particle steering.…”

Section: Forces On Spionsmentioning

confidence: 99%

“…while integrating over the whole area cross-section of the vessel. Since the relative permeability of tissue and blood is approximately 1 [65], only the permeability of vacuum µ 0 is taken into account for the medium of the background flow.…”

Section: Evaluation Of the Spion Distributionmentioning

confidence: 99%

How the Magnetization Angle of a Linear Halbach Array Influences Particle Steering in Magnetic Drug Targeting—A Systematic Evaluation and Optimization

Thalmayer,

Götz,

Fischer

2024

Symmetry

View full text Add to dashboard Cite

The main challenge in magnetic drug targeting lies in steering the magnetic particles, especially in deeper body layers. For this purpose, linear Halbach arrays are currently in focus. However, to the best of the authors’ knowledge, the impact of the magnetization angle between two neighboring magnets in Halbach arrays has not been investigated for particle steering so far. Therefore, in this paper, a systematic numerical parameter study of varying the magnetization angle of linear Halbach arrays is conducted. This is completed by undertaking a typical magnetic drug targeting scenario, where magnetic particles have to be steered in an optimized manner. This includes the calculation of the magnetic flux density, its gradient, the total magnetic energy, and the resulting magnetic force based on a fitting function for the different Halbach constellations in the context of examining their potential for predicting the particle distribution. In general, increased magnetization angles result in an increased effective range of the magnetic force. However, as there is a trade-off between a weak force on the weak side of the array and a simple manufacturing process, a magnetization angle of 90∘ is recommended. For evaluating the steering performance, a numerical or experimental evaluation of the particle distribution is mandatory.

show abstract

Investigation of the magnetic susceptibility properties of fresh and fixed mouse heart, liver, skeletal muscle and brain tissue

Cited by 7 publications

References 76 publications

Unexpected divergence in magnetoreceptor MagR from robin and pigeon linked to two sequence variations

Unexpected divergence in magnetoreceptor MagR from robin and pigeon linked to two sequence variations

Non-Stokesian dynamics of magnetic helical nanoswimmers under confinement

How the Magnetization Angle of a Linear Halbach Array Influences Particle Steering in Magnetic Drug Targeting—A Systematic Evaluation and Optimization

Contact Info

Product

Resources

About