Easy axes orientation dependent model for collective magnetic behaviour of zinc ferrite nanoparticles assembly

Konwar, Korobi; Kaushik, S. D.; Deb, Pritam

doi:10.1063/5.0016631

Cited by 2 publications

(8 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is seen that the coercivity ( H c ) and remanence ( H r ) have increased by lowering the temperature and shows a maximum at the lowest temperature (5 K). The nature of coercivity and remanence may be attributed to the predominance of Zeeman energy over thermal excitation energy. − The coercivity values are determined to be 37.9, 37.6, and 9.5 Oe for the CEIN, CEAIN, and CSE systems. The CSE system ensures the lowest coercivity.…”

Section: Results and Discussionmentioning

confidence: 98%

“…The absence of any other significant peaks ensures the absence of any anions. The observed structural property of the developed systems can impact the inherent magnetic behavior, − for which we perform an in-detail collective magnetic behavior.…”

Section: Results and Discussionmentioning

confidence: 99%

“…The slope obtained from a linear fit of the plot for relaxation rate 1/ T 1 against each metal concentration yields a longitudinal relaxation rate r 2 for the respective system. The linear fitting is considered by the expression where i = 1, 2; T i is the relaxation period, T i (0) is the contribution of diamagnetic counterpart toward relaxation, r i gives the relaxivity value, and C is the respective metal concentration . The proper fitting ensures faster longitudinal magnetic moment recovery with a higher slope value of 0.41 s –1 mmol –1 for CEIN, 0.35 s –1 mmol –1 for CEAIN, 0.39 s –1 mmol –1 for CE, 0.31 s –1 mmol –1 for CSE, and 0.28 s –1 mmol –1 for HCE at 3 T for a spin–lattice relaxation period.…”

Section: Results and Discussionmentioning

confidence: 99%

“…The effectiveness of a phantom image can be quantified by using a concentration-dependent relaxivity. The extent to which a phantom image can reduce T 1 and T 2 relaxation times gives the idea about r 1 and r 2 . However, dominance of one spin relaxation mechanism over another can be understood by considering the ratio of r 1 and r 2 .…”

Section: Results and Discussionmentioning

confidence: 99%

“…where i = 1, 2; T i is the relaxation period, T i (0) is the contribution of diamagnetic counterpart toward relaxation, r i gives the relaxivity value, and C is the respective metal concentration. 25 The proper fitting ensures faster longitudinal magnetic moment recovery with a higher slope value of 0.41 s −1 mmol −1 for CEIN, 0.35 s −1 mmol −1 for CEAIN, 0.39 s −1 mmol −1 for CE, 0.31 s −1 mmol −1 for CSE, and 0.28 s −1 mmol −1 for HCE at 3 T for a spin−lattice relaxation period. A small nonzero contribution of diamagnetic counterpart is observed during relaxation toward a longitudinal pathway.…”

Section: Zeta Potential and Cytotoxicity Analysismentioning

confidence: 98%

See 4 more Smart Citations

Structure-Correlated Magnetic Resonance Transverse Relaxivity Enhancement in Superparamagnetic Ensembles with Complex Anisotropy Landscape

et al. 2022

Self Cite

View full text Add to dashboard Cite

The aim of the work is to explore structurerelaxivity relationship by observing transverse relaxivity enhancement in magnetic resonance imaging (MRI) of differently organized superparamagnetic complex ensembles of zinc ferrite isotropic/anisotropic nanosystems. We observe that superparamagnetic systems show a correlation of MRI-transverse relaxivity, r 2 /r 1 , with spatial arrangement of nanoparticles, as well as magnetic easy axes and thermal-energy-dependent anisotropy energy landscape. The presence of highly random/partially aligned easy axes with enhanced anisotropy constant leads to modulation in transverse relaxation. As a result, we achieve highest contrast efficiency in compact ensemble of isotropic nanoparticles and hollow core ensemble. Indeed, core−shell ensemble with combined effect of aligned and randomly oriented easy magnetic axes shows a reduction in MRI contrast efficiency. However, we address a hypothesis for transverse contrast efficiency where we depict the correlation among MRI-transverse contrast efficiency with structural complexity of ensembles, differently arranged primary nanoparticles/magnetic easy axes, anisotropy constant, and collective magnetic behavior. In consequence, we simplify the limitation of quantum mechanical outer-sphere diffusion model of magnetic resonance relaxivity by neglecting the contribution of magnetization and introducing an anisotropy constant contribution with complex structure landscape of easy axes.

show abstract

Section: Results and Discussionmentioning

confidence: 98%

Section: Results and Discussionmentioning

confidence: 99%

Section: Results and Discussionmentioning

confidence: 99%

Section: Results and Discussionmentioning

confidence: 99%

Section: Zeta Potential and Cytotoxicity Analysismentioning

confidence: 98%

See 3 more Smart Citations

Structure-Correlated Magnetic Resonance Transverse Relaxivity Enhancement in Superparamagnetic Ensembles with Complex Anisotropy Landscape

et al. 2022

Self Cite

View full text Add to dashboard Cite

show abstract

Ni_1–xZn_xFe₂O₄@CoO (x = 0.25 and 0.50) Nanoparticles for Magnetic Resonance Imaging

Konwar,

Bora,

Kaushik

et al. 2023

ACS Appl. Nano Mater.

Self Cite

View full text Add to dashboard Cite

Nanomagnets with regulated magnetic properties are incredibly advantageous in the framework of magnetic resonance imaging (MRI) for medical imaging. This work aims to achieve an improved MRI-contrast signal by considering variation in octahedral site substitution of Zn 2+ ions in nanoensembles of Ni 1−x Zn x Fe 2 O 4 @CoO (x = 0.25 and 0.50) nanoparticles. We observe enhanced MRI-contrast efficiency in nanoensembles of Ni 0.75 Zn 0.25 Fe 2 O 4 @CoO with superior ground state magnetization of 210.6 μ B /cell and a higher asymmetric coercive field than that of Ni 0.5 Zn 0.5 Fe 2 O 4 @CoO. In addition, both systems show cell viability to a normal HEK cell line until 0.5 mM and no pro-tumorigenic activity until 1 mM. The ratio of transverse to longitudinal relaxivity (r 2 /r 1 ) gives a value of 30 for Ni 0.75 Zn 0.25 Fe 2 O 4 @CoO and 19.5 for Ni 0.5 Zn 0.5 Fe 2 O 4 @CoO, resulting in promising candidates for MRI-transverse contrast agents with a small metal concentration up to 0.375 mM. A superior MRI-contrast signal is achieved in Ni 0.75 Zn 0.25 Fe 2 O 4 @CoO. As a result, we successfully achieve enhancement in MRI-contrast efficiency by considering manipulation in octahedral site substitution in cellviable nanoensembles of Ni 1−x Zn x Fe 2 O 4 @CoO (x = 0.25 and 0.50) and attaining the significant association of anisotropy field strength and easy axes alignment toward proton dephasing in the MRI-relaxivity mechanism.

show abstract

Easy axes orientation dependent model for collective magnetic behaviour of zinc ferrite nanoparticles assembly

Cited by 2 publications

References 3 publications

Structure-Correlated Magnetic Resonance Transverse Relaxivity Enhancement in Superparamagnetic Ensembles with Complex Anisotropy Landscape

Structure-Correlated Magnetic Resonance Transverse Relaxivity Enhancement in Superparamagnetic Ensembles with Complex Anisotropy Landscape

Ni_1–xZn_xFe₂O₄@CoO (x = 0.25 and 0.50) Nanoparticles for Magnetic Resonance Imaging

Contact Info

Product

Resources

About

Easy axes orientation dependent model for collective magnetic behaviour of zinc ferrite nanoparticles assembly

Cited by 2 publications

References 3 publications

Structure-Correlated Magnetic Resonance Transverse Relaxivity Enhancement in Superparamagnetic Ensembles with Complex Anisotropy Landscape

Structure-Correlated Magnetic Resonance Transverse Relaxivity Enhancement in Superparamagnetic Ensembles with Complex Anisotropy Landscape

Ni1–xZnxFe2O4@CoO (x = 0.25 and 0.50) Nanoparticles for Magnetic Resonance Imaging

Contact Info

Product

Resources

About

Ni_1–xZn_xFe₂O₄@CoO (x = 0.25 and 0.50) Nanoparticles for Magnetic Resonance Imaging