Novel bifunctional nanomaterials as probes for bioimaging

• Main Author: Teo, Shiang Min.
• Other Authors: Tan Thatt Yang Timothy
• Format: Final Year Project
• Language: English
• Published: 2009
• Subjects: DRNTU::Engineering::Bioengineering
• Online Access: http://hdl.handle.net/10356/16296
• Institution: Nanyang Technological University

This work investigates the synthesis of bifunctional nanomaterials using two methods - doping of superparamagnetic Fe2O3 nanoparticles with Tb3+ via hydrothermal reaction, as well as direct deposition of Y2O3:Tb nanoparticles onto Fe2O3 nanoparticles. The nanoparticles produced by these two methods were investigated for their magnetic and fluorescent properties, in addition to their structural characteristics. Fe2O3 nanoparticles were used as a provider of magnetic properties while Tb3+ ions were used to provide fluorescence. Despite the strong fluorescence that were expected of Tb3+ ions, significant characteristic peaks were not observed from the emission spectra of the beta-FeOOH:Tb samples, possibly because fluorescence quenching due to Fe. Hence, rare earth and transition metals were used in place of Fe for their magnetic properties with further experiments carried out via hydrothermal reaction. Fluorescence was observed for the samples synthesized via the direct deposition method, but not all samples were well dispersed in hexane and displayed the proposed core-shell structure. Among which, Gd(OH)3:Tb, Gd2O3:Tb and Fe2O3(core)-Y2O3:Tb(shell) nanoparticles had fluorescence spectra with characteristic peaks of Tb3+, while SEM images showed the formation of nanorods for Gd(OH)3:Tb and Gd2O3:Tb, and TEM images showed some nanoparticles with core-shell structures for Fe2O3-Y2O3:Tb.