Recent applications of magnetic nanoparticles in biomedical applications, especially in
imaging diagnostics using MRI Magnetic Resonance Imaging engineering have attracted the
attention of scientists around the world. Currently in imaging diagnostics using MRI magnetic
resonance imaging, Tl contrast agents have become a traditional commodity, which is a
complex of paramagnetic ions with a large torque value like Gd3+ (7 unpaired electrons).
These Gd3+ ions are combined with molecules such as DTPA (diethylentriamine penta acetic
acid) and create Gd-DTPA chelate round complex structures. During the recovery process,
the interaction between the magnetic moment of the proton and the magnetic moment of the
paramagnetic ions causes the T1 time to be reduced, so the recovery rate R1 increases. The
concentration of agents is different in each cell tissue region, thus providing an effective
contrasting on MRI images. For nearly 10 years now, along with the development of
nanotechnology iron oxide (IO) nanoparticle having been strongly researched and actual
many commercial products that increase MRI contrast levels using this iron oxide material,
proving that iron oxides-MRI can give better quality of contrast level than Gd-DTPA because
iron oxide particles have a higher magnetic induction coefficient. IO-MRI substances can
reduce both T1 and T2, increasing MRI recovery rates in both Tl and T2 MRI modes. The
important requirements for MRI contrast increasing products are that magnetic nanoparticles
must have a relatively uniform particle distribution and magnetic saturation enough large, and
the coating materials must have good biological compatibility. While some commercial
products in the world, such as Resovist, use dextran as a coating material, with a 65 nm core
particle created from saturation of about 65 emu/g. Products with particle sizes in the 20-
40nm region such as AMI-227: Sinerem/Combidex are suitable for lymph and bone. In the
last 10 years, people have been studying to create superparamagnetic nanoparticles with a
particle size smaller than 20 nm (also known as microscopic if the particle size is D10 nm)
and especially iron oxide particles, marked with magnetic markers is intended for MRI
targeted imaging.