DNA sequences detection

Preliminary results of DNA sequence detection using the OFRR are thoroughly described by Suter, et al.32 The experimental setup described above for tracking the resonant mode shift is used. An OFRR with RI sensitivity of about 7 nm/RIU was produced and used for these experiments. The OFRR surface was functionalized with 3APS and then DMA was used as an amine-amine crosslinker. The single-stranded oligonucleotide capture probe was synthesized with an amine functional group connected to the 5 end by a 6-carbon linker, and has a 25 base-pair sequence. ... 

This diverse set of biosensing experimental demonstrations illustrates the flexibility of the OFRR device. Nearly any biomolecular recognition event can be detected. The examples illustrated with the previously described experiments include DNA sequence detection and virus detection through surface proteins. Additional biosensing examples for which the OFRR is well-suited include site-specific cleavage, protein-protein interactions, and cell genotype/phenotype identification through receptors. Furthermore, as shown by the theory outlined above, the OFRR can be accurately and precisely quantitative. 

Xu QH, Gaylord BS, Wang S, Bazan GC, Moses D, Heeger AJ (2004) Time-resolved energy transfer in DNA sequence detection using water-soluble conjugated polymers the role of electrostatic and hydrophobic interactions. Proc Natl Acad Sci USA 101 11634-11639... 

Hameed AAA, Andy PM (2008) Effect of surfactant on FRET and quenching in DNA sequence detection using conjugated polymers. Adv Funct Mater 18 2498-2509... 

Figure 13.15 Detection of a specific sequence of DNA by hybridization to a 32P-labelled cDNA probe. DNA is transferred to nitrocellulose and incubated with the probe. After washing, specific binding is visualized by autoradiography. The DNA sequence detected by the probe is present in lanes 2, 3 and 5 but not 1 and 4.

The development of assemblies of inorganic materials with biomolecules has emerged as a novel approach to the controlled fabrication of functionalized nanostructures and networks.5 The practice of DNA sequence detection is especially relevant for forensic sciences, food safety, genetics and other fields.6 The immobilization of single strand DNA probes onto solid materials such as noble metal nanoparticles has proved to be the basis for a multitude of quite different nanobiotech-nological and biomedical applications, including the DNA driven assembly of nanoparticles and biosensors.5-11... 

S.R. Mikkelsen, Electrochemical biosensors for DNA sequence detection, Electroanalysis, 8 (1996) 15-19. 

Figure 8.17 Schematic diagram for detection of three unique DNA sequences via hybridization of target DNA with magnetic bead-conjugated probe DNA followed by hybridization with three different detection probe DNA-modified semiconductor nanopaiticles, ZnS, CdS, and PbS. Dissolution and electrochemical stripping yielded three well-resolved peaks corresponding to the specific metal, and hence, unique DNA sequences detected.76 (Reprinted with permission from J. Wang et aL, J. Am. Chem. Soc. 2003,125, 3214-3215. Copyright 2003 American Chemical Society.) (See color insert.)...

Evidence of virus virus specific antigens present viral DNA sequences detected viral mRNA present virus can sometimes be rescued. 

Kumar, N., Dorfman, A., and Hahm, J. (2006). Ultrasensitive DNA sequence detection of Bacillus anthracis using nanoscale ZnO sensor arrays. Nanotechnology 17 2875-2881. 

MacAskill A, Crawford D, Graham D, Faulds K (2009) DNA sequence detection using surface-enhanced resonance Raman spectroscopy in a homogeneous multiplexed assay. Anal Chem 81 8134-8140... 

Vercoutere, W. Akeson, M., Biosensors for DNA sequence detection, Curr Opin. Chem. Biol. 2002, 6, 816-822... 

Yan, H. and Xu, B. Q. Towards rapid DNA sequencing Detecting single-stranded DNA with a solid-state nanopore. Small 2, 310-312 (2006). 

Intercalator hybridization labels are complex molecules that have a planar aromatic group. Several methods for indicator-based electrochemical sequence specific to DNA detection have been reported. Wang et al. [41] described the hybridization detection of short DNA sequences related to HIV virus genome due to the chronopotentiometric transduction of Co(phen) as an hybridization label. Electrochemiluminescense assays have also been reported by Carter etal. [42] for specific DNA sequence detection. 

Recently, Mascini s group has also used this method, in combination with disposable graphite screen-printed electrodes, initially for model DNA sequence detection [70] and more recently for the quantitation of human apolipoprotein E genotypes [71] in both cases, daunomycin was used as an indicator species. Daunomycin is a DNA intercalant bearing both quinone and hydroquinone functionalities, and Mascini s group used constant-current oxidation of the hydroquinone moiety for detection. Their detection limit of 1 pg mL target DNA resulted in the need for PCR amplification prior to DNA detection. 

Biological Applications Nucleic acid hybridization DNA fingerprinting DNA sequencing detecting nucleic acids, cells, pathogens counting embryo-blasts ... 

Electrochemical biosensors were developed for detection and discrimination of either target DNA sequence or single nucleotide polymorphisms. DNA sequence detections have various applications such as detection of target genes, discrimination and classification of various organisms and also detection of genetic based disorders. 

The number of studies on self-assembled monolayers (SAMs) has grown over the past years. SAMs are molecular layers formed on a surface when it is immersed in a solution containing molecules that specifically interact with the surface. Due to the efficiency and simplicity of the self-assembly technique, the immobilization of thiol- or disulfide-modified DNA on gold electrodes was reported in the literatureSAMs at mercury electrodes were also reported by Ostatna and Palecek. Specific DNA sequence detection in clinical samples (undiluted and untreated human serum and urine samples) were performed on a ternary interface involving hexanedithiol (HDT) co-immobilized with the thiolated capture probe (SHCP) on gold surfaces, followed by the incorporation of 6-mercapto-l-hexanol (MCH) as the diluent. ... 

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