Resonance Frequency Shift of Vibrating Amorphous Ribbon via Surface Adsorption of Magnetic Fe 3 O 4 Nanoparticles

In this study, Fe 40 Ni 38 Mo 4 B 18 amorphous ferromagnetic ribbon was used as a vibrating reed sensor to detect Fe 3 O 4 magnetic nanoparticles. The sensor surface was not subjected to any treatment: the amorphous ribbon was used directly as a sensor. Nanoparticles with a diameter of 25 nm in ddH 2 O were dripped on the sensor surface at different rates. Different amounts of magnetic nanoparticles ranging from 1 to 12 µg were dripped, and it was observed that the sensor resonance frequency decreased linearly with the mass of magnetic nanoparticles dripped. It was shown that 1 µg MNP could be easily detected by the vibrating reed method.