Article
Chemistry, Physical
Nilimesh Das, Pratik Sen
Summary: The molecular-level structure and dynamics of solvent media greatly influence their functionality. Understanding the heterogeneity of solvent structure and dynamics is important, and analytical predictions have provided insights into viscosity decoupling. This approach offers a simple yet unique physical picture for understanding solvent media.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Physics, Fluids & Plasmas
Michael S. Rusanov, Vladimir S. Zverev, Ekaterina A. Elfimova
Summary: A simple theory of the dynamic response of a ferrofluid to an AC magnetic field has been obtained, taking into account interparticle dipole-dipole interactions and field amplitude dependence. The theory extends the applicability of existing theories for weak and strong AC field amplitudes, and analyzes the susceptibility spectra. The effects of interparticle interactions and field amplitude on the dynamic response of ferrofluids are opposite, leading to relaxation processes determined by the characteristic relaxation times for an ideal paramagnetic gas at certain field amplitudes.
Article
Chemistry, Physical
Barnabas Horvath, Peter Decsi, Istvan Szalai
Summary: In this study, we propose an expansion method within the mean spherical approximation (MSA) framework to obtain the coefficients of different nonlinear terms in magnetic fluids. The linear and nonlinear dynamic susceptibilities are calculated by Fourier expanding the frequency-dependent magnetic susceptibility and performing a field expansion of magnetization. The frequency dependence of higher order susceptibilities is determined based on the Debye relaxation of magnetic dipoles. Our results based on MSA are consistent with the limiting case of the Debye-Weiss theory. We determine the range of applicability of the expansion method in terms of field strength and frequencies, and show that a 7th order expansion is sufficient to predict the magnitudes of the susceptibility components up to the 4th harmonic relevant for magnetic fluids.
JOURNAL OF MOLECULAR LIQUIDS
(2022)
Article
Mechanics
M. A. Kanso, V. Chaurasia, E. Fried, A. J. Giacomin
Summary: In this study, the rotational diffusivity of coronavirus particles in suspension was calculated using general rigid bead-rod theory. It was found that the triangular shape of the spike bulbs significantly decreases the rotational diffusivity of the virus particles.
Article
Materials Science, Multidisciplinary
C. A. M. Iglesias, J. C. R. de Araujo, J. Xavier, L. M. Silva, M. S. Nunes, J. H. de Araujo, S. N. de Medeiros, C. C. Pla Cid, M. A. Morales, E. F. Silva, M. Gamino, M. A. Correa, F. Bohn
Summary: This study addresses the inequality for the initial magnetic susceptibility and demonstrates that its violation is a signature of the existence of ferromagnetic exchange interactions between single-domain nanoparticles in a collective system. The findings are supported by experimental results and a generalized theoretical model.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
Guidobeth Saez, Eduardo Saavedra, Nicolas Vidal-Silva, Juan Escrig, Eugenio E. Vogel
Summary: In this study, we investigated the dynamic properties of a Bloch Point singularity confined in a diameter modulated magnetic nanowire. Our micromagnetic simulations revealed the emergence of two distinct modes with energies above the lowest energy mode in the presence of the Bloch Point. These modes were differently affected by changes in system geometry and the application of a magnetic field.
RESULTS IN PHYSICS
(2022)
Article
Chemistry, Physical
Yoshihiko Nishikawa, Atsushi Ikeda, Ludovic Berthier
Summary: We numerically study the equilibrium relaxation dynamics of a two-dimensional Mari-Kurchan glass model. The model displays similar dynamical behavior to conventional glass-formers, despite its simple structural correlations.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Instruments & Instrumentation
Philip J. Camp
Summary: Magnetosomes, which are linear chains of magnetic nanoparticles found in magnetotactic bacteria, have potential applications in biomedicine. Simulations have been used to study the static and dynamic properties of noninteracting magnetosomes, and compare them to theoretical predictions for magnetic filaments.
SMART MATERIALS AND STRUCTURES
(2023)
Article
Materials Science, Multidisciplinary
Sota Hamada, Kota Aoki, Keita Kodama, Kentaro Nashimoto, Yuko Ichiyanagi
Summary: Mg1-xZnxFe2O4 (x = 0.0, 0.2, 0.4, 0.6, 0.8) nanoparticles surrounded by amorphous SiO2 were synthesized to improve biocompatibility and magnetization for hyperthermia therapy. Particles sized 18 nm generated the most heat, showing potential for killing cancer cells.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2022)
Article
Engineering, Multidisciplinary
Bin Bao, Quan Wang, Nan Wu, Shaoyi Zhou
Summary: This research introduces a hand-held piezoelectric energy-harvesting structure for portable human-motion energy harvesting, and analyzes the dynamic changes of electric and magnetic fields during rotation through simulation and treadmill experiments. The results demonstrate that the device can generate a certain voltage at specific speeds and charge a capacitor accordingly.
Article
Materials Science, Multidisciplinary
Matthew J. Fox, Ashlee Aiello, Shize Yang, Paul C. Trulove, David P. Durkin, Elena Cimpoiasu
Summary: Biocomposites containing magnetic nanoparticles have the potential to combine the unique properties of nanoparticles with the strong mechanical and sustainable properties of natural fibers. This study investigates how the structural and magnetic properties of these biocomposite materials are affected by increasing metal loading, finding that higher metal loading enhances nanoparticle heterogeneity and agglomeration.
MATERIALS CHEMISTRY AND PHYSICS
(2024)
Article
Physics, Applied
Proloy T. Das, H. Nhalil, M. Schultz, A. Grosz, L. Klein
Summary: The magnetization dynamics of nanomagnetic beads with a diameter ranging from 80 to 250 nm were studied using a high-resolution elliptical planar Hall effect (EPHE) sensor integrated with a fluidic channel. The dynamics were well described with Cole-Cole and exponential decay models for frequency and time domains, respectively. The potential use of EPHE sensors in lab-on-a-chip applications was discussed.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Mechanics
Michal Rajnak, Bystrik Dolnik, Patrik Hodermarsky, Katarina Paulovicova, Roman Cimbala, Milan Timko, Peter Kopcansky
Summary: Magnetic nanoparticles in a non-polar ferrofluid can reassemble in external electric fields, influencing the magnetic response of ferrofluids. Under a static electric field, the magnetic susceptibility of a ferrofluid based on insulating oil and iron oxide nanoparticles decreases with increasing voltage, partially due to temperature increase. Other mechanisms such as nanoparticle trapping and aggregation induced by the electric field also contribute to the susceptibility drop.
Article
Chemistry, Physical
Ejaj Tarif, Nilimesh Das, Pratik Sen
Summary: Traditionally, deviation from Stokes-Einstein-Debye (SED) p relation in terms of viscosity dependence of medium dynamics, i.e., t(x) 8( ?/T )(p) with p ? 1, is taken as a signature of dynamic heterogeneity. However, it does not guarantee medium heterogeneity, as the decoupling may also originate from the deviation of the basic assumption of SED. We developed a method to find a stronger relation between viscosity decoupling (p ? 1) and dynamic heterogeneity in terms of rotational motion, using solvatochromic probe measurements at different excitations or emissions.
JOURNAL OF PHYSICAL CHEMISTRY B
(2023)
Article
Materials Science, Multidisciplinary
R. G. Gontijo, A. B. Guimaraes
Summary: This study numerically investigates the effect of a rotating magnetic field on heat dissipation in magnetic hyperthermia. A validated code based on Langevin Dynamics is used to simulate the problem. The results show nonlinear response of the magnetic suspension to the amplitude and frequency of the field. The relaxation time and volume fraction of particles also influence the thermal response. The analysis provides insights into the system's behavior based on timescales and micro-structural features of the suspension.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Connor S. Smith, Shehaab Savliwala, Sara C. Mills, Jennifer S. Andrew, Carlos Rinaldi, David P. Arnold
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2020)
Article
Chemistry, Multidisciplinary
Brittany D. Partain, Mythreyi Unni, Carlos Rinaldi, Kyle D. Allen
JOURNAL OF CONTROLLED RELEASE
(2020)
Article
Engineering, Biomedical
Zhiyuan Zhao, Carlos Rinaldi
PHYSICS IN MEDICINE AND BIOLOGY
(2020)
Article
Energy & Fuels
Ivanise Guilherme Branco, Kacoli Sen, Carlos Rinaldi
CHEMICAL ENGINEERING AND PROCESSING-PROCESS INTENSIFICATION
(2020)
Article
Materials Science, Multidisciplinary
N. C. Rost, K. Sen, S. Savliwala, I Singh, S. Liu, M. Unni, L. Raniero, C. Rinaldi
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2020)
Article
Multidisciplinary Sciences
Andreina Chiu-Lam, Edward Staples, Carl J. Pepine, Carlos Rinaldi
Summary: The study reports on an mCPA containing superparamagnetic iron oxide nanoparticles that can increase the preservation time of cryopreserved organs through nanowarming, reduce damage caused by slow rewarming, and have low cytotoxicity. The results demonstrate that this formulated mCPA is suitable for perfusion, vitrification, and nanowarming of whole organs.
Review
Chemistry, Applied
Angelie Rivera-Rodriguez, Carlos M. Rinaldi-Ramos
Summary: Magnetic nanoparticles are of interest for biomedical applications due to their biocompatibility, tunable surface chemistry, and ability to be actuated by applied magnetic fields. They exhibit a dynamic response to time-varying magnetic fields, enabling their use as tracers in magnetic particle imaging and for conversion of magnetic energy to heat.
ANNUAL REVIEW OF CHEMICAL AND BIOMOLECULAR ENGINEERING, VOL 12, 2021
(2021)
Article
Orthopedics
B. D. Partain, Q. Zhang, M. Unni, J. Aldrich, C. M. Rinaldi-Ramos, S. Narayanan, K. D. Allen
Summary: This study uses X-ray photon correlation spectroscopy (XPCS) to evaluate dynamic interactions between intact cartilage and biofluids at the nanometer scale. Results show that cartilage ECM mobility varies with length scale and fluid environment, demonstrating the importance of biosolid-biofluid interactions in dictating ECM dynamics. XPCS can provide unique insights into spatially resolved cartilage ECM mobility.
OSTEOARTHRITIS AND CARTILAGE
(2021)
Article
Multidisciplinary Sciences
Mythreyi Unni, Shehaab Savliwala, Brittany D. Partain, Lorena Maldonado-Camargo, Qingteng Zhang, Suresh Narayanan, Eric M. Dufresne, Jan Ilavsky, Pawel Grybos, Anna Koziol, Piotr Maj, Robert Szczygiel, Kyle D. Allen, Carlos M. Rinaldi-Ramos
Summary: The diffusion behavior of polymer-coated inorganic nanoparticles in synovial fluid can be well described by the Stokes-Einstein relationship, with an effective medium viscosity much smaller than the macroscopic low shear viscosity of the fluid. The additional viscous dissipation in the effective medium viscosity is attributed to the presence of polymer segments, shedding light on the diffusive behavior of these nanoparticles in complex and crowded biological environments such as the joint.
Article
Chemistry, Physical
Zhi Wei Tay, Shehaab Savliwala, Daniel W. Hensley, K. L. Barry Fung, Caylin Colson, Benjamin D. Fellows, Xinyi Zhou, Quincy Huynh, Yao Lu, Bo Zheng, Prashant Chandrasekharan, Sindia M. Rivera-Jimenez, Carlos M. Rinaldi-Ramos, Steven M. Conolly
Summary: This study explores the advantages and new discoveries of superferromagnetic iron oxide nanoparticle chains in medical imaging, demonstrating their potential to improve image resolution and signal-to-noise ratio, as well as investigating their potential applications in medical imaging.
Article
Biotechnology & Applied Microbiology
Nicole S. Sarna, Leyda Marrero-Morales, Ryan DeGroff, Angelie Rivera-Rodriguez, Sitong Liu, Andreina Chiu-Lam, Hayden J. Good, Carlos M. Rinaldi-Ramos
Summary: This study presents anatomically correct 3D-printed mouse phantoms for magnetic particle imaging (MPI) studies. These phantoms, based on the Digimouse 3D whole body mouse atlas, incorporate cavities representative of different tumors and organs, allowing for the evaluation of MPI tracer dose effects. The results demonstrate the accuracy of the proposed image analysis method for tracer mass estimation and highlight the importance of tracer distribution details on the limit of detection in MPI.
BIOENGINEERING & TRANSLATIONAL MEDICINE
(2022)
Article
Chemistry, Multidisciplinary
Sitong Liu, Matthew Po, Anahita Heshmat, Evan Anguish, Jennifer Andrew, Carlos M. Rinaldi-Ramos
Summary: Hafnium oxide nanoparticles (HNCs) formulated using flash nanoprecipitation (FNP) exhibit high X-ray attenuation and low cost, making them attractive as computed tomography (CT) contrast agents. A simple 3D-printed FNP mixer was used to produce HNCs with controlled hydrodynamic size ranging from 100-300 nm. Evaluation in both pre-clinical small animal scanner and clinical scanner showed that the HNCs provide approximately 1.5 times greater contrast enhancement compared to the commercially used iodinated molecular contrast agent Omnipaque.
JOURNAL OF NANOPARTICLE RESEARCH
(2023)
Article
Chemistry, Physical
Victor G. Rivera-Llabres, Kara N. Gentry, Matthew Po, Carlos M. Rinaldi-Ramos
Summary: The study reports the formulation of size tunable magnetic alginate microparticles (MAMs) using a 3D flow-focusing microfluidic device. The stability of iron oxide nanoparticles (IONPs) coated with polyethylene glycol (PEG) in alginate and calcium ethylenediamine tetraacetic acid solutions is investigated. The average size and coefficient of variance of MAMs are found to vary with droplet and continuous phase flow rates and viscosities. Crosslinking and drying of droplets result in smaller MAMs with a low coefficient of variance. The findings can guide future research on the role of MAM size in different applications.
PARTICLE & PARTICLE SYSTEMS CHARACTERIZATION
(2023)
Article
Nanoscience & Nanotechnology
Lily E. Diodati, Sitong Liu, Carlos M. Rinaldi-Ramos, Brent S. Sumerlin
Summary: Covalent adaptable networks (CANs) combine the stability of thermosets with the reprocessability of thermoplastics through the incorporation of dynamic crosslinks. In this study, we incorporated Fe3O4 nanoparticles as fillers in a vinylogous urethane vitrimer to facilitate induction heating processing. Despite the common decrease in flow rate and reprocessing difficulty caused by the inclusion of inorganic fillers, the presence of Fe3O4 nanoparticles did not affect the flow behavior of the vitrimer, possibly due to the nanoparticles' catalytic effect on dynamic exchange chemistry. Two methods of incorporating the nanoparticles were employed, and the vitrimers with covalently crosslinked nanoparticles exhibited a shorter relaxation time compared to those with blended nanoparticles. The magnetic character of the Fe3O4 nanoparticles enabled self-healing of the vitrimer composite materials during induction heating.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Sitong Liu, Anahita Heshmat, Jennifer Andrew, Izabella Barreto, Carlos M. M. Rinaldi-Ramos
Summary: Magnetic particle imaging (MPI) is a novel imaging modality that tracks the distribution of superparamagnetic iron oxide nanoparticles (SPIONs) for biomedical applications. However, it lacks anatomical information. Computed tomography (CT) provides high-resolution anatomical information. Combining MPI and CT could offer a multimodal imaging agent with improved diagnostic capabilities.
NANOSCALE ADVANCES
(2023)
