Event Information

Kui Yu (National Research Council of Canada)
Synthesis and Characterization of Photoluminescent Colloidal Semiconductor Nanocrystals for Bio-Imaging Applications
Abstract:
The development of novel bio-imaging probes with intrinsic characteristics that can overcome the limitations of traditional fluorescent molecules is a multi-disciplinary research area that has attracted significant attention. Photo-luminescent (PL) colloidal semiconductor quantum dots (QDs), which are spherical in shape with diameter on the order of 1 – 10 nm, have demonstrated themselves as great candidates for replacing traditional organic dyes in certain bio-imaging applications. Due to size-dependent quantum confinement, quantum dots such as CdSe can emit from blue to red depending on their sizes. This presentation addresses our efforts on the synthesis and characterization of PL quantum dots including binary and ternary (such as homogeneous and gradient CdTeSe and CdZnS) and layered CdSe/CdTe/CdSe semiconductor nanocrystals. Our comprehensive study on the structure determination of the ternary systems with solid state 113Cd Nuclear Magnetic Resonance (NMR), in addition to other techniques such as X-ray diffraction (XRD), is dealt with. The results demonstrate that solid state NMR is a vital tool in the arsenal of characterization techniques available for nanomaterials. In addition to our recent investigation on the bio-distribution of nano-crystals inside live mice, our study on dispersing media affecting the photoluminescent properties of our quantum dots is address, together with the investigation on the origin of photoluminescence via our PL dynamic study and up-conversion study. The insights gained from our comprehensive study on the synthesis and characterization of PL quantum dots facilitate the development of novel bio-imaging probes such as those aimed at molecular imaging.

Host: Jie Liu

Tuesday, January 23, 2007, 11:40am
Departmental Seminar