Faas, Henryk M. published the artcileAccelerated 19F·MRI detection of matrix metalloproteinase-2/-9 through responsive deactivation of paramagnetic relaxation enhancement, Application In Synthesis of 42074-68-0, the publication is Contrast Media & Molecular Imaging (2019), 4826520/1-4826520/13, database is CAplus and MEDLINE.
Paramagnetic gadolinium ions (GdIII), complexed within DOTA-based chelates, have become useful tools to increase the magnetic resonance imaging (MRI) contrast in tissues of interest. Recently, “on/off” probes serving as 19F·MRI biosensors for target enzymes have emerged that utilize the increase in transverse (T*2 or T2) relaxation times upon cleavage of the paramagnetic GdIII center. Mol. 19F·MRI has the advantage of high specificity due to the lack of background signal but suffers from low signal intensity that leads to low spatial resolution and long recording times. In this work, an “on/off” probe concept is introduced that utilizes responsive deactivation of paramagnetic relaxation enhancement (PRE) to generate 19F longitudinal (T1) relaxation contrast for accelerated mol. MRI. The probe concept is applied to matrix metalloproteinases (MMPs), a class of enzymes linked with many inflammatory diseases and cancer that modify bioactive extracellular substrates. The presence of these biomarkers in extracellular space makes MMPs an accessible target for responsive PRE deactivation probes. Responsive PRE deactivation in a 19F biosensor probe, selective for MMP-2 and MMP-9, is shown to enable mol. MRI contrast at significantly reduced exptl. times compared to previous methods. PRE deactivation was caused by MMP through cleavage of a protease substrate that served as a linker between the fluorine-containing moiety and a paramagnetic GdIII-bound DOTA complex. Ultrashort echo time (UTE) MRI and, alternatively, short echo times in standard gradient echo (GE) MRI were employed to cope with the fast 19F transverse relaxation of the PRE active probe in its “on-state.” Upon responsive PRE deactivation, the 19F·MRI signal from the “off-state” probe diminished, thereby indicating the presence of the target enzyme through the associated neg. MRI contrast. Null point 1H·MRI, obtainable within a short time course, was employed to identify false-pos. 19F·MRI responses caused by dilution of the contrast agent.
Contrast Media & Molecular Imaging published new progress about 42074-68-0. 42074-68-0 belongs to chlorides-buliding-blocks, auxiliary class Chloride,Benzyl chloride,Benzene, name is 2-Chlorotrityl chloride, and the molecular formula is C19H14Cl2, Application In Synthesis of 42074-68-0.
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https://en.wikipedia.org/wiki/Chloride,
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