Tracking single quantum dot and its spectrum in free solution with controllable thermal diffusion suppression

TitleTracking single quantum dot and its spectrum in free solution with controllable thermal diffusion suppression
Publication TypeJournal Article
Year of Publication2008
AuthorsLi Q, Han R, Meng XX, Gai HW, Yeung ES
Journal TitleAnalytical Biochemistry
Volume377
Pages176-181
Date Published06
Type of ArticleArticle
ISBN Number0003-2697
Accession NumberISI:000255918000010
Keywordsagarose, AQUEOUS-SOLUTION, dehydrated, field, FLUORESCENCE SPECTROSCOPY, force microscopy, MOLECULE, PROTEIN MOLECULES, SEMICONDUCTOR NANOCRYSTALS, single quantum dot spectrum, spectroscopy, SURFACTANTS, thermal diffusion control
Abstract

Thermal motions of semiconductor quantum dots (QDs) are suppressed on a dehydrated agarose-modified surface. The diffusion coefficients (D) of particles can be controlled by modifying the surface with an appropriate agarose concentration. The value of D is more than 100 times lower than the theoretical value when the dried agarose surface is made with an 8% agarose solution. This makes it possible to real-time record the diffusion process of single particles and single molecules in low-viscosity solution. A transmission grating installed in front of the charge-coupled device separates the QD fluorescence into the zeroth-order and first-order spectrum. Therefore, the spectrum of dynamic QDs is tracked on the modified surface. Tracking the dynamic QD spectral image is a promising method to explore the process of the molecular interactions in the physiological buffer. (c) 2008 Elsevier Inc. All rights reserved.

DOI10.1016/j.ab.2008.03.017
Alternate JournalAnal. Biochem.