Preparation of plasmonic gold nanoparticles and their bio-photonics applications

Abstract

Metallic nanoparticles (e.g., gold nanospheres (AuNSs) and gold nanorods (AuNRs)) display the unique feature of localized surface plasmon resonance (LSPR). This feature occurs when the incident photon frequency is resonant with the collective oscillation of the conduction-band electrons of the nanoparticles, giving them remarkable optical absorption and scattering properties. LSPR is highly sensitive to the size and shape of gold nanoparticles (AuNPs) and the external medium. These peculiar features make them useful for bio-imaging and bio-sensing applications. In this thesis, we investigated the optical properties and biocompatibility of AuNPs formulations with different shapes, sizes, and functionalization. We further used AuNPs to develop surface plasmon resonance (SPR)/surface enhanced Raman spectroscopy (SERS) based platforms for bio-imaging and bio-sensing applications. The successful development of such platforms will help doctors and surgeons to better screen and identify cancer and other diseases at an early stage.