The functionalization of the SPIONs was qualitatively confirmed by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) recorded with an IR Prestige 21 from Shimadzu between 650 and 4000 cm -1 at a resolution of 4 cm -1 . The data was corrected with the internal atmospheric correction (Shimadzu IRsolution 1.60) removing residual H2O and CO2 vibration bands and normed to the interval borders 650 and 4000 cm -1 .