Quantum dot antibody DOCX

Title	Quantum dot antibody
Author	Rohan Mehta
Pages	7
File Size	1.2 MB
File Type	DOCX
Total Downloads	6
Total Views	643

Summary

Zach McCaw, TJ Rider, Patrick Ross, Liz Wall Final Model Project 4/20/2010 Biomolecule Labeling Using Quantum Dot Barcodes Introduction In his paper “Less Is More in Medicine,” Paul Alivisatos describes the concept of quantum dot barcodes. Quantum dot barcodes are unique microscale arrays of quantum...

Description

Zach McCaw, TJ Rider, Patrick Ross, Liz Wall Final Model Project 4/20/2010 Biomolecule Labeling Using Quantum Dot Barcodes Introduction In his paper "Less Is More in Medicine," Paul Alivisatos describes the concept of quantum dot barcodes. Quantum dot barcodes are unique microscale arrays of quantum dots that can be identied by analyzing the spectrum of light they emit when exposed to a single light source (usually ultraviolet – see Fig. 1). These arrays can be encapsulated in synthetc polymer beads, which are then coated in such a way that they have a bonding afnity for a partcular molecule. Using the speciicity of this bonding afnity and the uniqueness of a given barcode'scs emission signature, quantum dot barcodes can be used to "tag" molecules for detecton.1 Fig. 1 Quantum dots exposed to ultraviolet light and a spectral analysis of the light they emit2 When quantum dots are exposed to ultraviolet light, they emit light of a partcular color. Because they are nanoscale objects, the wavelength of that light is determined by the size of each individual partcle. Larger quantum dots emit light closer to the red end of the spectrum, while smaller quantum dots emit bluer light. This occurs because the energy levels in quantum dots are more numerous and more closely spaced, so the QDs can absorb lower-energy photos, such as those on the red end of the spectrum; the converse is true for smaller quantum dots.3 In the case of multple quantum dots encased in a polymer bead, the emission spectra of the combined multcolored quantum dots create the unique identtes of the individual "barcodes" (Fig. 2) One bead might contain 30% yellow dots, 40% red dots, 20% green dots, and 10% blue dots. When that bead is exposed to ultraviolet light, the intensity of red light would be highest, followed by yellow, then green, then blue. The compositon of light intensites creates a unique signature for that barcode, which can be used to identfy which quantum dots have found their targets and where....