Attachment of quantum dots or fluorescent molecules to gold nanoparticles has a variety of optical labeling and sensory applications. In this study, we use both e-beam lithography and DNA origami to examine the fluorescence enhancement of fluorescent molecules and quantum dots with a systematic approach to understanding the contribution of gold nanoparticle size and interparticle spacing. The unique design of our patterns allows us to study the effects of size and spacing of the gold nanoparticles on the enhancement of fluorescence in one quick study with constant conditions – removing undesirable effects such as differences in concentration of quantum dots or other chemistry differences that plague multiple experiments. We also discuss the fluorescence and bonding of CdSe/ZnS quantum dots to both gold as well as DNA for use in self assembled DNA constructs. Specifically, bioconjugated CdSe/ZnS core/shell quantum dots were synthesized and functionalized with MPA using both traditional ligand exchange as well as newly developed in situ functionalization techniques used to increase the quantum yield of the quantum dots. We will present fluorescent images showing results of optimal size and spacing for fluorescence as well as demonstrating attachment chemistry of the quantum dots.

Date Published: 13 May 2015
PDF: 8 pages
Proc. SPIE 9481, Image Sensing Technologies: Materials, Devices, Systems, and Applications II, 94810X (13 May 2015); doi: 10.1117/12.2180638

Published in SPIE Proceedings Vol. 9481:
Image Sensing Technologies: Materials, Devices, Systems, and Applications II
Nibir K. Dhar; Achyut K. Dutta, Editor(s)