Self-diffusion measurements by a mobile single-sided NMR sensor with improved magnetic field gradient

2006 ◽  
Vol 180 (2) ◽  
pp. 229-235 ◽  
Author(s):  
D.G. Rata ◽  
F. Casanova ◽  
J. Perlo ◽  
D.E. Demco ◽  
B. Blümich
Keyword(s):  
Magnetic Field ◽  
Field Gradient ◽  
Magnetic Field Gradient ◽  
Self Diffusion

An alternating pulsed magnetic field gradient apparatus for NMR self-diffusion measurements

1982 ◽  
Vol 49 (3) ◽  
pp. 411-424 ◽  
Author(s):  
Mirko I Hrovat ◽  
Chester O Britt ◽  
Tony C Moore ◽  
Charles G Wade
Keyword(s):  
Magnetic Field ◽  
Field Gradient ◽  
Magnetic Field Gradient ◽  
Pulsed Magnetic Field ◽  
Self Diffusion

ALGORITHM FOR THE EVALUATION OF THE SELF-DIFFUSION COEFFICIENT OF SMALL MOLECULES, USING THE NMR MAGNETIC FIELD GRADIENT METHOD

2002 ◽  
Vol 16 (19) ◽  
pp. 2875-2884 ◽  
Author(s):  
M. TODICA ◽  
A. V. POP
Keyword(s):  
Magnetic Field ◽  
Diffusion Coefficient ◽  
Small Molecules ◽  
Field Gradient ◽  
Spin Echo ◽  
Magnetic Field Gradient ◽  
Pure Water ◽  
The Self ◽  
Self Diffusion ◽  
Self Diffusion Coefficient

Different methods of investigation of the spin-echo attenuation, in the NMR pulsed field gradient experiments, were analyzed in order to optimize the measurements of the self-diffusion coefficient of the small molecules of simplest liquids. A particular algorithm of representation of the experimental data is proposed in order to eliminate the effect of the residual gradient. This algorithm, tested for pure water, give results in accord with the literature.

Spectroscopic imaging of human disease

1996 ◽  
Vol 54 ◽  
pp. 884-885
Author(s):  
D.J. Meyerhoff
Keyword(s):  
Magnetic Field ◽  
Magnetic Resonance ◽  
Field Gradient ◽  
Human Disease ◽  
Morphological Changes ◽  
Magnetic Field Gradient ◽  
Spectroscopic Imaging ◽  
Resonance Spectroscopy ◽  
Tissue Water

Magnetic Resonance Imaging (MRI) observes tissue water in the presence of a magnetic field gradient to study morphological changes such as tissue volume loss and signal hyperintensities in human disease. These changes are mostly non-specific and do not appear to be correlated with the range of severity of a certain disease. In contrast, Magnetic Resonance Spectroscopy (MRS), which measures many different chemicals and tissue metabolites in the millimolar concentration range in the absence of a magnetic field gradient, has been shown to reveal characteristic metabolite patterns which are often correlated with the severity of a disease. In-vivo MRS studies are performed on widely available MRI scanners without any “sample preparation” or invasive procedures and are therefore widely used in clinical research. Hydrogen (H) MRS and MR Spectroscopic Imaging (MRSI, conceptionally a combination of MRI and MRS) measure N-acetylaspartate (a putative marker of neurons), creatine-containing metabolites (involved in energy processes in the cell), choline-containing metabolites (involved in membrane metabolism and, possibly, inflammatory processes),

scholarly journals Magnetic hybrid materials interact with biological matrices

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Christine Gräfe ◽  
Elena K. Müller ◽  
Lennart Gresing ◽  
Andreas Weidner ◽  
Patricia Radon ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Field Gradient ◽  
Hybrid Materials ◽  
Biomedical Application ◽  
Magnetic Field Gradient ◽  
Apical Cell ◽  
Cell Type ◽  
Cell Layers ◽  
Barrier Model

Abstract Magnetic hybrid materials are a promising group of substances. Their interaction with matrices is challenging with regard to the underlying physical and chemical mechanisms. But thinking matrices as biological membranes or even structured cell layers they become interesting with regard to potential biomedical applications. Therefore, we established in vitro blood-organ barrier models to study the interaction and processing of superparamagnetic iron oxide nanoparticles (SPIONs) with these cellular structures in the presence of a magnetic field gradient. A one-cell-type–based blood-brain barrier model was used to investigate the attachment and uptake mechanisms of differentially charged magnetic hybrid materials. Inhibition of clathrin-dependent endocytosis and F-actin depolymerization led to a dramatic reduction of cellular uptake. Furthermore, the subsequent transportation of SPIONs through the barrier and the ability to detect these particles was of interest. Negatively charged SPIONs could be detected behind the barrier as well as in a reporter cell line. These observations could be confirmed with a two-cell-type–based blood-placenta barrier model. While positively charged SPIONs heavily interact with the apical cell layer, neutrally charged SPIONs showed a retarded interaction behavior. Behind the blood-placenta barrier, negatively charged SPIONs could be clearly detected. Finally, the transfer of the in vitro blood-placenta model in a microfluidic biochip allows the integration of shear stress into the system. Even without particle accumulation in a magnetic field gradient, the negatively charged SPIONs were detectable behind the barrier. In conclusion, in vitro blood-organ barrier models allow the broad investigation of magnetic hybrid materials with regard to biocompatibility, cell interaction, and transfer through cell layers on their way to biomedical application.

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