Proceedings Article | 22 May 2007
Proc. SPIE. 6592, Bioengineered and Bioinspired Systems III
KEYWORDS: Semiconductors, Proteins, Biomedical optics, Cancer, Luminescence, Quantum dots, Laser Doppler velocimetry, Cadmium sulfide, Neurons, Absorption
Nanoscale functionalization of semiconductor quantum dots (SQDs) with biomedical structures is promising for many
applications and novel studies of intrinsic properties of both constituent systems. Results of our study of structural
properties of the nanoscale functionalized SQDs such as CdS, and ZnS-capped CdSe SQDs, conjugated with
biomolecules such as short peptides and cells are presented. We study CdS SQDs functionalized with peptides specially
composed of the following amino acid chains: CGGGRGDS, CGGGRVDS, CGGIKVAV, and CGGGLDV, where R is
arginine, D - aspartic acid, S - serine, V - valine, K - lysine and L is Levine. As will be seen the cysteine (C) amino acid
links to CdS SQDs via the thiol link, the GGG sequences of glycine (G) amino acid, provide a spacer in the amino acid
chain. At the same time the RGDS, RVDS, IKAV, and LDV sequences have selective bonding affinities to specialized
transmembrane cellular structures known as integrins of neurons and MDA-MB-435 cancer cells, respectively. We found
that the quantum confinement and functionalizing in biomedical environments plays in altering and determining the
electronic, optical, and vibrational properties of these nanostructures as well as demonstrated the effectiveness to use
semiconductor quantum dots as integrin sensitive biotags.
