Abstract：
:Magnetic Particle Imaging (MPI) is a promising medical imaging technique for visualizing the three-dimensional distribution of tracer materials, specifically iron oxide nanoparticles (IONP). The optimization of magnetic nanoparticles (MNP) plays an essential role to improve the image resolution and sensitivity of imaging techniques. In this work, the optimization of commercial IONP (EMG 700, Ferrotec) coated with anionic surfactants was carried out using magnetic separation (MS) technique, by a low gradient magnetic separation (LGMS) (<15 T/m) method, to improve their performance as MPI tracers. The magnetophoretical behavior of the samples in different concentrations ranging from 2 to 120 mmol/L was investigated over 24 h of separation. The samples were characterized by Dynamic Light Scattering (DLS), AC Susceptibility (ACS), Magnetic Particle Spectroscopy (MPS) and they were imaged in a preclinical MPI scanner, before and after magnetic separation. DLS results showed that by increasing the concentration from 2 to 120 mmol/L the hydrodynamic diameter of MNP decrease from 75 nm to 47 nm and size distribution decrease from 0.19 to 0.11 after 4 min MS. In addition, the MPS results demonstrated the third harmonic amplitude normalized to the iron amount 〖(A〗_3^*) and harmonic ratio (A_5/A_3) of signal increase from 8.38 to 10.59 Am2/kg (Fe) and 24.21 to 26.60, respectively. Furthermore, the MPI images of the samples after separation showed higher MPI resolution. Therefore, LGMS can be considered as a valuable method to narrow and control the size distribution of MNP for MPI.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Arsalani S,Loewa N,Kosch O,Radon P,Baffa O,Wiekhorst Fdoi
10.1088/1361-6560/abcd19subject
Has Abstractpub_date
2020-11-23 00:00:00eissn
0031-9155issn
1361-6560pub_type
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