Superparamagnetic cobalt ferrite nanoparticles as <i>T</i> <sub>2</sub> contrast agent in MRI: in vitro study
Zahra Mohammadi, Neda Attaran, Ameneh Sazgarnia, Seyed Ali Mousavi Shaegh, Alireza Montazerabadi
Abstract
Superparamagnetic cobalt ferrite nanoparticles (CoFe 2 O 4 ) possess favourite advantages for theranostic applications. Most of previous studies reported that CoFe 2 O 4 magnetic nanoparticles (MNPs) are suitable candidates for induction of hyperthermia and transfection agents for drug delivery. The present study synthesized and investigated the potential use of CoFe 2 O 4 as a contrast agent in magnetic resonance imaging (MRI) by using a conventional MRI system. The CoFe 2 O 4 were synthesized using co‐precipitation method and characterized by TEM, XRD, FTIR, EDX and VSM techniques. Relaxivities r 1 and r 2 of CoFe 2 O 4 were then calculated using a 1.5 Tesla clinical magnetic field. The cytotoxicity of CoFe 2 O 4 was evaluated by the MTT assay. Finally, the optimal concentrations of MNPs for MRI uses were calculated through the analysis of T 2 weighted imaging cell phantoms. The superparamagnetic CoFe2O4 NPs with an average stable size of 10.45 nm were synthesized. Relaxivity r 1 , 2 calculations resulted in suitable r 2 and r 2 / r 1 with values of 58.6 and 51 that confirmed the size dependency on relaxivity values. The optimal concentration of MNPs for MR image acquisition was calculated as 0.154 mM. Conclusion: CoFe 2 O 4 synthesized in this study could be considered as a suitable T 2 weighted contrast agent because of its high r 2 / r 1 value.