scholarly journals Aggregation Properties of Albumin in Interacting with Magnetic Fluids

2021 ◽  
Vol 22 (19) ◽  
pp. 10734
Author(s):  
Elena N. Velichko ◽  
Elina K. Nepomnyashchaya ◽  
Maksim A. Baranov ◽  
Alexey N. Skvortsov ◽  
Ivan V. Pleshakov ◽  
...  
Keyword(s):  
Magnetic Nanoparticles ◽  
Magnetic Nanoparticle ◽  
Magnetic Particles ◽  
Correlation Spectroscopy ◽  
Interaction Processes ◽  
Low Concentrations ◽  
Nanoparticle Aggregates ◽  
Magnetite Particles ◽  
Spiral Structures ◽  
The Stability

In this study, interactions of Fe3O4 magnetic nanoparticles with serum albumin biomolecules in aqueous solutions were considered. The studies were conducted with the laser correlation spectroscopy and optical analysis of dehydrated films. It was shown that the addition of magnetite to an albumin solution at low concentrations of up to 10−6 g/L led to the formation of aggregates with sizes of up to 300 nm in the liquid phase and an increase in the number of spiral structures in the dehydrated films, which indicated an increase in their stability. With a further increase in the magnetite concentration in the solution (from 10−4 g/L), the magnetic particles stuck together and to albumin, thus forming aggregates with sizes larger than 1000 nm. At the same time, the formation of morphological structures in molecular films was disturbed, and a characteristic decrease in their stability occurred. Most stable films were formed at low concentrations of magnetic nanoparticles (less than 10−4 g/L) when small albumin–magnetic nanoparticle aggregates were formed. These results are important for characterizing the interaction processes of biomolecules with magnetic nanoparticles and can be useful for predicting the stability of biomolecular films with the inclusion of magnetite particles.

scholarly journals Ultrasonic Studies of Emulsion Stability in the Presence of Magnetic Nanoparticles

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
A. Józefczak ◽  
R. Wlazło
Keyword(s):  
Magnetic Field ◽  
Magnetic Nanoparticles ◽  
Acoustic Waves ◽  
Magnetic Particles ◽  
Emulsion Stability ◽  
High Energy ◽  
Pickering Emulsions ◽  
Ultrasound Waves ◽  
Acoustic Study ◽  
Magnetite Particles

Pickering emulsions are made of solid particle-stabilized droplets suspended in an immiscible continuous liquid phase. A magnetic emulsion can be obtained using magnetic particles. Solid magnetic nanoparticles are adsorbed strongly at the oil-water interface and are able to stabilize emulsions of oil and water. In this work emulsions stabilized by magnetite nanoparticles were obtained using high-energy ultrasound waves and a cavitation mechanism and, next, their stability in time was tested by means of acoustic waves with a low energy, without affecting the structure. An acoustic study showed high stability in time of magnetic emulsions stabilized by magnetite particles. The study also showed a strong influence of an external magnetic field, which can lead to changes of the emulsion properties. It is possible to control Pickering emulsion stability with the help of an external stimulus—a magnetic field.

scholarly journals Applications of Thermoresponsive Magnetic Nanoparticles

2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Ibrahim Yildiz ◽  
Banu Sizirici Yildiz
Keyword(s):  
Drug Delivery ◽  
Magnetic Nanoparticles ◽  
Magnetic Separation ◽  
Magnetic Nanoparticle ◽  
Magnetic Particles ◽  
Polymeric Coatings ◽  
Biomedical Sciences ◽  
Comprehensive Review ◽  
Material Sciences ◽  
Number Of Publications

In recent years, magnetic nanoparticles carrying thermoresponsive polymeric coatings have gained increasing attention in material sciences due to the fact that resultant platforms offer controllable modalities such as imaging, drug delivery, and magnetic separation. As a result, novel materials including biosensors, therapeutic platforms, imaging agents, and magnetic separators have been realized. Since the number of publications reporting the applications of thermoresponsive magnetic nanoparticle has increased steadily over the years, a comprehensive review will be beneficial. In this paper, we aim to review publications studying applications of thermoresponsive nanoparticles in biomedical sciences as well as in environmental and chemical sciences. The paper also briefly discusses chemical formulations, characterizations, and properties of the thermoresponsive magnetic particles and then provides future outlooks.

scholarly journals Investigation of Magnetic Nanoparticle Motion under a Gradient Magnetic Field by an Electromagnet

2018 ◽  
Vol 2018 ◽  
pp. 1-5 ◽  
Author(s):  
Weizhong Wei ◽  
Zhen Wang
Keyword(s):  
Magnetic Field ◽  
Finite Element ◽  
Electromagnetic Field ◽  
Magnetic Nanoparticles ◽  
Particle Motion ◽  
Biomedical Applications ◽  
Magnetic Nanoparticle ◽  
Magnetic Particles ◽  
Magnetic Force ◽  
Gradient Magnetic Field

Finite element numerical simulations were carried out in 2D geometry to calculate the magnetic force on magnetic nanoparticles under a specially fabricated electromagnet. The particle motion was modeled by a system of ordinary differential equations. The snapshots of trajectories of 4000 MNPs with and without magnetic field were analyzed and qualitatively found to be in agreement with camera visualizations of MNP movement in a container. The results of the analysis could be helpful for the design of electromagnetic field and motion analysis of magnetic particles for the delivery of magnetic materials in biomedical applications.

scholarly journals Influence of Sonication on the Stability and Thermal Properties of Al2O3Nanofluids

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Monir Noroozi ◽  
Shahidan Radiman ◽  
Azmi Zakaria
Keyword(s):  
Thermal Diffusivity ◽  
Particle Concentration ◽  
Correlation Spectroscopy ◽  
Photopyroelectric Technique ◽  
Absorption Properties ◽  
Transmission Electron ◽  
Low Concentrations ◽  
Higher Power ◽  
Ultrasonic Devices ◽  
The Stability

Nanofluids containing Al2O3nanoparticles (either 11 or 30 nm in size) dispersed in distilled water at low concentrations (0.125–0.5 wt%) were prepared using two different ultrasonic devices (a probe and a bath sonicator) as the dispersant. The effect of the ultrasonic system on the stability and thermal diffusivity of the nanofluids was investigated. Thermal diffusivity measurements were conducted using a photopyroelectric technique. The dispersion characteristics and morphology of the nanoparticles, as well as the optical absorption properties of the nanofluids, were studied using photon cross correlation spectroscopy with a Nanophox analyzer, transmission electron microscopy, and ultraviolet-visible spectroscopy. At higher particle concentration, there was greater enhancement of the thermal diffusivity of the nanofluids resulting from sonication. Moreover, greater stability and enhancement of thermal diffusivity were obtained by sonicating the nanofluids with the higher power probe sonicator prior to measurement.

scholarly journals Investigations into the Biocompatibility of Nanohydroxyapatite Coated Magnetic Nanoparticles under Magnetic Situation

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Qing Li ◽  
Gang Zhou ◽  
Tong Wang ◽  
Yongzhao Hou ◽  
Xuliang Deng ◽  
...  
Keyword(s):  
Magnetic Nanoparticles ◽  
Magnetic Nanoparticle ◽  
Magnetic Particles ◽  
X Ray Diffraction ◽  
New Approach ◽  
X Ray ◽  
In Vitro Experiment ◽  
Transmission Electron ◽  
Mesenchyme Stem Cells

Regenerative medicine consisting of cells and materials offers a new approach for repairing and regenerating the organs and tissues. More and more researches focused on the magnetic nanobiomaterials due to its superior advantages to traditional materials. However, the toxicity of nanosized magnetic particles cannot be ignored, especially under the magnetic situation. This study aims to study the biocompatibility of nanohydroxyapatite (n-HA-) coated magnetic nanoparticles under the magnetic situation. n-HA-coated magnetic nanoparticles were fabricated through an ultrasound-assisted coprecipitation method. Subsequently, these materials were analyzed by transmission electron microscope (TEM) and X-ray diffraction (XRD) and then were cultured with mesenchyme stem cells derived from human bone marrow (hMSC-BM). In vitro experiment proved the satisfactory biocompatibility of n-HA-coated magnetic nanoparticles. These important factors (ALP, OCN, and OPN) influence the osteogenic differentiation of hMSC-BM. It was found that the hMSC-BM with combination of n-HA/Fe3O4and magnetic stimulation presented higher degree of osteoblast-related markers than that in each alone. This research demonstrated that a novel nanohydroxyapatite coated magnetic nanoparticle is safe under the magnetic situation. Therefore, these n-HA-coated magnetic nanoparticles are promising biomagnetic materials for future applications.

scholarly journals Evaluating the Performance of a Magnetic Nanoparticle-Based Detection Method Using Circle-to-Circle Amplification

Biosensors ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 173
Author(s):  
Darío Sánchez Martín ◽  
Reinier Oropesa-Nuñez ◽  
Teresa Zardán Gómez de la Torre
Keyword(s):  
Magnetic Nanoparticles ◽  
Magnetic Nanoparticle ◽  
Diagnostic Method ◽  
Detection Method ◽  
Particle Surface ◽  
Diagnostic Assay ◽  
Functionalized Magnetic Nanoparticles ◽  
Target Sequences ◽  
The Stability ◽  
Synthetic Target

This work explores several issues of importance for the development of a diagnostic method based on circle-to-circle amplification (C2CA) and oligonucleotide-functionalized magnetic nanoparticles. Firstly, the performance of the detection method was evaluated in terms of sensitivity and speed. Synthetic target sequences for Newcastle disease virus and Salmonella were used as model sequences. The sensitivity of the C2CA assay resulted in detection of 1 amol of starting DNA target with a total amplification time of 40 min for both target sequences. Secondly, the functionalization of the nanoparticles was evaluated in terms of robustness and stability. The functionalization was shown to be very robust, and the stability test showed that 92% of the oligos were still attached on the particle surface after three months of storage at 4 °C. Altogether, the results obtained in this study provide a strong foundation for the development of a quick and sensitive diagnostic assay.

Kinetics of Various 99mTc-Sn-Pyrophosphate Compounds in the Rat

1977 ◽  
Vol 16 (04) ◽  
pp. 157-162 ◽  
Author(s):  
C. Schümichen ◽  
B. Mackenbrock ◽  
G. Hoffmann
Keyword(s):  
Normal Saline ◽  
Half Life ◽  
Compound A ◽  
Short Half Life ◽  
Low Concentrations ◽  
The Stability ◽  
Kinetics Of ◽  
In Vitro Stability

SummaryThe bone-seeking 99mTc-Sn-pyrophosphate compound (compound A) was diluted both in vitro and in vivo and proved to be unstable both in vitro and in vivo. However, stability was much better in vivo than in vitro and thus the in vitro stability of compound A after dilution in various mediums could be followed up by a consecutive evaluation of the in vivo distribution in the rat. After dilution in neutral normal saline compound A is metastable and after a short half-life it is transformed into the other 99mTc-Sn-pyrophosphate compound A is metastable and after a short half-life in bone but in the kidneys. After dilution in normal saline of low pH and in buffering solutions the stability of compound A is increased. In human plasma compound A is relatively stable but not in plasma water. When compound B is formed in a buffering solution, uptake in the kidneys and excretion in urine is lowered and blood concentration increased.It is assumed that the association of protons to compound A will increase its stability at low concentrations while that to compound B will lead to a strong protein bond in plasma. It is concluded that compound A will not be stable in vivo because of a lack of stability in the extravascular space, and that the protein bond in plasma will be a measure of its in vivo stability.

Tuning the Magnetic Vortex State in Magnetite Nanodiscs for Remote Control of Biological Signalling

2019 ◽  
Author(s):  
Danijela Gregurec ◽  
Alexander W. Senko ◽  
Andrey Chuvilin ◽  
Pooja Reddy ◽  
Ashwin Sankararaman ◽  
...  
Keyword(s):  
Remote Control ◽  
Ion Channels ◽  
Ground State ◽  
Magnetic Particles ◽  
Colloidal Stability ◽  
Vortex State ◽  
Magnetic Vortex ◽  
Electron Holography ◽  
Dipole Interactions ◽  
Magnetite Particles

In this work, we demonstrate the application of anisotropic magnetite nanodiscs (MNDs) as transducers of torque to mechanosensory cells under weak, slowly varying magnetic fields (MFs). These MNDs possess a ground state vortex configuration of magnetic spins which affords greater colloidal stability due to eliminated dipole-dipole interactions characteristic of isotropic magnetic particles of similar size. We first predict vortex magnetization using micromagnetic stimulations in sub-micron anisotropic magnetite particles and then use electron holography to experimentally investigate the magnetization of MNDs 98–226 nm in diameter. When MNDs are coupled to MFs, they transition between vortex and in-plane magnetization allowing for the exertion of the torque on the pN scale, which is sufficient to activate mechanosensitive ion channels in cell membranes.<br>

scholarly journals CLytA-DAAO Chimeric Enzyme Bound to Magnetic Nanoparticles. A New Therapeutical Approach for Cancer Patients?

2021 ◽  
Vol 22 (3) ◽  
pp. 1477
Author(s):  
María Fuentes-Baile ◽  
Elizabeth Pérez-Valenciano ◽  
Pilar García-Morales ◽  
Camino de Juan Romero ◽  
Daniel Bello-Gil ◽  
...  
Keyword(s):  
Magnetic Nanoparticles ◽  
Colorectal Carcinoma ◽  
Acid Oxidase ◽  
Oxygen Species ◽  
Cell Models ◽  
Amino Acid Oxidase ◽  
Direct Addition ◽  
Alginate Capsules ◽  
Anti Cancer ◽  
The Stability

D-amino acid oxidase (DAAO) is an enzyme that catalyzes the oxidation of D-amino acids generating H2O2. The enzymatic chimera formed by DAAO bound to the choline-binding domain of N-acetylmuramoyl-L-alanine amidase (CLytA) induces cytotoxicity in several pancreatic and colorectal carcinoma and glioblastoma cell models. In the current work, we determined whether the effect of CLytA-DAAO immobilized in magnetic nanoparticles, gold nanoparticles, and alginate capsules offered some advantages as compared to the free CLytA-DAAO. Results indicate that the immobilization of CLytA-DAAO in magnetic nanoparticles increases the stability of the enzyme, extending its time of action. Besides, we compared the effect induced by CLytA-DAAO with the direct addition of hydrogen peroxide, demonstrating that the progressive generation of reactive oxygen species by CLytA-DAAO is more effective in inducing cytotoxicity than the direct addition of H2O2. Furthermore, a pilot study has been initiated in biopsies obtained from pancreatic and colorectal carcinoma and glioblastoma patients to evaluate the expression of the main genes involved in resistance to CLytA-DAAO cytotoxicity. Based on our findings, we propose that CLytA-DAAO immobilized in magnetic nanoparticles could be effective in a high percentage of patients and, therefore, be used as an anti-cancer therapy for pancreatic and colorectal carcinoma and glioblastoma.

scholarly journals Understanding intracellular nanoparticle trafficking fates through spatiotemporally resolved magnetic nanoparticle recovery

2021 ◽  
Author(s):  
Emily Sheridan ◽  
Silvia Vercellino ◽  
Lorenzo Cursi ◽  
Laurent Adumeau ◽  
James A. Behan ◽  
...  
Keyword(s):  
Decision Making ◽  
Magnetic Nanoparticles ◽  
Magnetic Nanoparticle ◽  
Magnetic Extraction

We describe how magnetic nanoparticles can be used to study intracellular nanoparticle trafficking, and how magnetic extraction may be integrated with downstream analyses to investigate nanoscale decision-making events.

Sign in / Sign up

Export Citation Format

Share Document