Dendrimer facilitated synthesis of multifunctional lanthanide based hybrid nanomaterials for biological applications

A poly(amido amine) (PAMAM) dendrimer has been successfully used for the first time as a linking agent for the synthesis of a luminescent lanthanide based multifunctional nanohybrid (YPO4:Tb3+@Fe3O4). Characterization of the materials was done by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), vibrating sample magnetometer (VSM), and thermogravimetric analysis (TGA). The HRTEM images showed spindle shaped YPO4:Tb3+@Fe3O4 in the presence of a PAMAM dendrimer which is due to the incorporation of the Fe3O4 nanoparticles in the branches of the PAMAM dendrimer when they are attached on the surfaces of the YPO4:Tb3+ nanorods. Photoluminescence studies showed the Tb-O charge transfer transition which is produced by electron delocalization from the filled 2p shell of the O2- to the partially filled 4f shell of Tb3+. The nanohybrid materials yielded a specific absorption rate (SAR) value of 39.22 W g(-1) of magnetite under the influence of an AC magnetic field of 110 Oe and 425 kHz frequency. Biocompatibility of the developed hybrid nanomaterials was evaluated in vitro by assessing their cytotoxicity on human cervical cancer cells (HeLa cells) using a sulforhodamine B (SRB) assay. These YPO4:Tb3+@Fe3O4 nanohybrids have potential biomedical applications in the area of imaging and magnetic hyperthermia