Characterization of magnetic Fe_3O_4@SiO_2 nanoparticles with fluorescent properties for potential multipurpose imaging and theranostic applications

摘要

Fe_3O_4 magnetic nanoparticles (MNPs) were produced using hydrothermal synthesis and coated with tetraethyl orthosilicate (TEOS) where Fe_3O_4@SiO_2 MNPs with fluorescent properties were obtained. Structural characterization of the nanoparticles was performed using X-ray diffraction, scanning electron microscopy and transmission electron microscopy. Structural investigations confirmed that nanoparticles were in core@shell form. Chemical characterizations were performed using Fourier-transform infrared spectroscopy and energy-dispersive X-ray spectroscopy. Chemical investigations confirm that TEOS coating was successfully formed SiO_2 shells on Fe_3O_4 nanoparticles. Magnetic characterizations revealed that nanoparticles show superparamag-netic properties which make them a suitable candidate for magnetic hyper-thermia and magnetic resonance imaging (MRI) applications. Increased thickness of SiO_2 shell in nanoparticle structure results in decreased magnetic saturation values. Fluorescence properties of the nanoparticles were confirmed using fluorescence spectroscopy. Increased SiO_2 shell thickness results in increased fluorescent intensity. It was confirmed that Fe_3O_4@SiO_2 nanoparticle has the potential to be used in medical applications such as MRI, fluorescence imaging and magnetic hyperthermia, and so on.