Published online 3 March 2006
Methods Online |
Homogeneous point mutation detection by quantum dot-mediated two-color fluorescence coincidence analysis
1Department of Mechanical Engineering, The Johns Hopkins University Baltimore, MD 21218, USA 2Whitaker Biomedical Engineering Institute, The Johns Hopkins University Baltimore, MD 21218, USA 3Department of Pathology, The Johns Hopkins University Baltimore, MD 21218, USA 4Department of Oncology, The Johns Hopkins University Baltimore, MD 21218, USA 5Department of Gynecology and Obstetrics, The Johns Hopkins University Baltimore, MD 21218, USA
*To whom correspondence should be addressed. Tel: +1 410 516 7086; Fax: 1 410 516 7254; Email: thwang{at}jhu.edu
Received April 6, 2005. Revised July 5, 2005. Accepted February 14, 2006.
This report describes a new genotyping method capable of detecting low-abundant point mutations in a homogeneous, separation-free format. The method is based on integration of oligonucleotide ligation with a semiconductor quantum dot (QD)-mediated two-color fluorescence coincidence detection scheme. Surface-functionalized QDs are used to capture fluorophore-labeled ligation products, forming QD-oligonucleotide nanoassemblies. The presence of such nanoassemblies and thereby the genotype of the sample is determined by detecting the simultaneous emissions of QDs and fluorophores that occurs whenever a single nanoassembly flows through the femtoliter measurement volume of a confocal fluorescence detection system. The ability of this method to detect single events enables analysis of target signals with a multiple-parameter (intensities and count rates of the digitized target signals) approach to enhance assay sensitivity and specificity. We demonstrate that this new method is capable of detecting zeptomoles of targets and achieve an allele discrimination selectivity factor >105.
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
H.-C. Yeh, C. M. Puleo, T. C. Lim, Y.-P. Ho, P. E. Giza, R. C. C. Huang, and T.-H. Wang A microfluidic-FCS platform for investigation on the dissociation of Sp1-DNA complex by doxorubicin Nucleic Acids Res., December 4, 2006; 34(21): e144 - e144. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. M.E. Azzazy, M. M.H. Mansour, and S. C. Kazmierczak Nanodiagnostics: A New Frontier for Clinical Laboratory Medicine Clin. Chem., July 1, 2006; 52(7): 1238 - 1246. [Abstract] [Full Text] [PDF] |
||||

