Investigations of the effective parameters on the synthesis of monodispersed magnetic Fe3O4 by solvothermal method for biomedical applications

Monodispersed magnetite nanoparticles were obtained by investigating the different synthesis parameters of the solvothermal method. The morphology and chemical structure of the Fe3O4 nanoparticles were characterized by Fourier transform infrared spectrometer (FT-IR), X-ray diffraction (XRD), Scanning electron microscope (SEM), Transmission electron microscope (TEM), Dynamic Light Scattering (DLS) and Vibrating sample magnetometer (VSM). Results indicated that without the addition of water, it forms the minor phase of iron instead of magnetite. Furthermore, the size of nanoparticles is tunable in the range of 117.7 to 217.6 nm by changing the amounts of water, PSSMA and NaOH. The amount of PSSMA restricts the growth of the nanoparticles and narrow the size distribution and a hydrophilic surface was obtained. Synthesized magnetite nanoparticles were successfully conjugated with carbon dots. The resulting nanoparticles exhibited good fluorescence characteristics. Cytotoxicity tests confirmed that nanoparticles are non-toxic. Both magnetite and C-dots/Fe3O4 nanoparticles are good potential candidates for biomedical applications specifically for bioimaging and biosensing in the future.