Magnetic performance of Synomag® nanoparticles in various environments

This work is an assessment of changes in magnetic properties of magnetic nanoparticles in various biological environments. To mimic variations in biological conditions, we have evaluated magnetic performance of Synomag® nanoparticles in two experiments: the effect of viscosity by varying the ratio of glycerol/water mixture and the effect of immobilization after blocking the Brownian relaxation by freeze-drying (to mimic uptake in macrophages). The magnetic response was measured with the Superparamagnetic quantifier. Synomag® exhibits a slight decrease (7.9%) of magnetic response under increased viscosity from η1=0.95 to η6=259.71 mPa.s, and a dramatic magnetic signal drop (78.2%) after freeze-drying. Synomag® nanoparticles are less sensitive to viscosity due  to an additional  relaxation mechanism of disordered spins within the nanoflowers. However, the magnetic performance has been reduced due to the blocking of Brownian relaxation after immobilization.   Int. J. Mag. Part. Imag. 6(2), Suppl. 1, 2020, Article ID: 2009022, DOI: 10.18416/IJMPI.2020.2009022