Terbium doped SnO sub(2) nanoparticles as white emitters and SnO sub(2):5Tb/Fe sub(3)O sub(4) magnetic luminescent nanohybrids for hyperthermia application and biocompatibility with HeLa cancer cells

SnO sub(2):5Tb (SnO sub(2) doped with 5 at% Tb super(3+)) nanoparticles were synthesised by a polyol method and their luminescence properties at different annealing temperatures were studied. Characterization of nanomaterials was done by X-ray diffraction (XRD), Fourier transformation infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and vibrating sample magnetometry (VSM). XRD studies indicate that the prepared nanoparticles were of tetragonal structures. Upon Tb super(3+) ion incorporation into SnO sub(2), Sn super(4+) changes to Sn super(2+) and, on annealing again at higher temperature, Sn super(2+) changes to Sn super(4+). The prepared nanoparticles were spherical in shape. Sn-O vibrations were found from the FTIR studies. In photoluminescence studies, the intensity of the emission peaks of Tb super(3+) ions increases with the increase of annealing temperature, and emission spectra lie in the region of white emission in the CIE diagram. CCT calculations show that the SnO sub(2):5Tb emission lies in cold white emission. Quantum yields up to 38% can be obtained for 900 degree C annealed samples. SnO sub(2):5Tb nanoparticles were well incorporated into the PVA polymer and such a material incorporated into the polymer can be used for display devices. The SnO sub(2):5Tb/Fe sub(3)O sub(4) nanohybrid was prepared and investigated for hyperthermia applications at different concentrations of the nanohybrid. This achieves a hyperthermia temperature (42 degree C) under an AC magnetic field. The hybrid nanomaterial SnO sub(2):5Tb/Fe sub(3)O sub(4) was found to exhibit biocompatibility with HeLa cells (human cervical cancer cells) at concentrations up to 74% for 100 mu g L super(-1). Also, this nanohybrid shows green emission and thus it will be helpful in tracing magnetic nanoparticles through optical imaging in vivo and in vitro application.