SQUID measurements showed superparamagnetic properties with a blocking temperature around 155 K. In addition it was observed that neither sodium citrate nor Triton X-100 influences the magnetic properties of the nanoparticles. 
SQUID
X-ray diffraction pattern and Fourier Transform Infrared analysis confirmed the presence of pure magnetite. 
X-ray diffraction pattern
X-ray diffraction pattern and Fourier Transform Infrared analysis confirmed the presence of pure magnetite. 
Fourier Transform Infrared analysis