The impact of polymer coatings on XXXX nanoparticles performance as MRI contrast agents: a comparative study.

@entity3703 @entity1933 @entity19792 @entity13528
BACKGROUND: Superparamagnetic @entity1933 nanoparticles (SPIONs) are the most commonly used negative MRI contrast agent which affect the transverse (T2) relaxation time. The aim of the present study was to investigate the impact of various polymeric coatings on the performance of @entity3703 nanoparticles as MRI contrast agents. METHODS: Ferrofluids based on @entity3703 ( @entity13528 ) nanoparticles (SPIONs) were synthesized via chemical co-precipitation method and coated with different biocompatible polymer coatings including @entity19792 , chitosan and dextran. RESULTS: The bonding status of different polymers on the surface of the @entity3703 nanoparticles was confirmed by the Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA). The vibrating sample magnetometer (VSM) analysis confirmed the superparamagnetic behavior of all synthesized nanoparticles. The field-emission scanning electron microscopy (FE-SEM) indicated the formation of quasi-spherical nanostructures with the final average particle size of 12-55 nm depending on the type of polymer coating, and X-ray diffraction (XRD) determined inverse spinel structure of @entity3703 nanoparticles. The ferrofluids demonstrated sufficient colloidal stability in deionized water with the zeta potentials of -24.2, -16.9, +31.6 and -21 mV for the naked SPIONs, and for dextran, chitosan and @entity19792 coated SPIONs, respectively. Finally, the magnetic relaxivities of water based ferrofluids were measured on a 1.5 T clinical MRI instrument. The r2/r1 value was calculated to be 17.21, 19.42 and 20.71 for the dextran, chitosan and @entity19792 coated SPIONs, respectively. CONCLUSIONS: The findings demonstrated that the value of r2/r1 ratio of @entity19792 modified SPIONs is higher than that of some commercial contrast agents. Therefore, it can be considered as a promising candidate for T2 MRI contrast agent.
