Preliminary experiments for detection of reflected signals from magnetic nanoparticles by ultrasound

The conventional magnetic particle imaging (MPI) requires large coils and high power inputs that generate a steep magnetic field gradient to reduce image artifacts, without which the blurring of reconstructed images occur. Therefore, a new imaging system based on vibrating magnetic nanoparticles (MNPs) that does not use an alternating magnetic field was proposed to solve this problem. It was observed that the reflection signals from the MNPs could be detected using focused ultrasound. Preliminary experiments were performed to clarify the reflection signal corresponding to the MNPs concentration with an image using a diagnostic ultrasound imaging system. As a result, the MNPs reflection signal’s ultrasound image was not acquired at an MNP concentration of 0.6 mol/L(Fe) or less. Therefore, a detailed examination of the concentration and particle size was required to detect the signal from MNPs. Int. J. Mag. Part. Imag. 6(2), Suppl. 1, 2020, Article ID: 2009014, DOI: 10.18416/IJMPI.2020.2009014