Here we report design, synthesis and characterization of highly sensitive, specific and stable in biological systems fluorescent probes for point mutation detection in DNA. The tandems of 3'- and 5'-mono- and bis-pyrene conjugated oligo(2'-O-methylribonucleotides), protected by 3'-"inverted" thymidine, were constructed and their potential as new instruments for genetic diagnostics was studied. ...

miRNAs have emerged as new biomarkers for the detection of a wide variety of cancers. By employing duplex-specific nuclease for signal amplification and gold nanoparticles (AuNPs) as the carriers of detection probes, a novel electrochemical assay of miRNAs was performed. The method is based on conversion of the well-known colorimetric assay into electrochemical analysis with enhanced sensitivit...

The sensitivity and specificity of two non-radioactive spot hybridization assays for hepatitis B virus DNA (HBV-DNA) using biotin and digoxygenin-labelled DNA probes were investigated in parallel in 122 serum samples from patients with chronic hepatitis B and 50 controls. The results were compared with an isotopic technique using a 32P-labelled probe. HBV-DNA was detected in 56 (80%) out of 70 ...

We report a method for improving the sensitivity of label-free optical biosensors based on in-situ synthesis of DNA probes within porous silicon structures. The stepwise attachment of up to 15mer probes inside 30 nm mesopores was accomplished through a series of phosphoramidite reactions. In this work, a porous silicon waveguide was utilized as the sensor structure. Synthesis of DNA probe, as w...

A DNA piezoelectric biosensing method for real-time detection of Escherichia coli O157:H7 in a circulating-flow system was developed in this study. Specific probes [a 30-mer oligonucleotide with or without additional 12 deoxythymidine 5'-monophosphate (12-dT)] for the detection of E. coli O157:H7 gene eaeA, synthetic oligonucleotide targets (30 and 104 mer) and PCR-amplified DNA fragments from ...

Small DNA circles can occur in Nature, for example as protein-constrained loops, and can be synthesized by a number of methods. Such small circles provide tractable systems for the study of the structure, thermodynamics and molecular dynamics of closed-circular DNA. In the present article, we review the occurrence and synthesis of small DNA circles, and examine their utility in studying the pro...

A DNA microarray was developed to detect bacterial genes conferring resistance to macrolides and related antibiotics. A database containing 65 nonredundant genes selected from publicly available DNA sequences was constructed and used to design 100 oligonucleotide probes that could specifically detect and discriminate all 65 genes. Probes were spotted on a glass slide, and the array was reacted ...

Using probes specific for several oncogenes/proto-oncogenes we have performed gel blot hybridization analyses of genomic DNA isolated from the sea urchin Strongylocentrotus droebachiensis. Probes prepared from v-erbB, v-myc, c-myb and v-fps were found to hybridize with discrete fragments of HindIII digested genomic DNA. In contrast, probes prepared from v-abl, v-fos, v-sis, v-src, and v-mos eit...

This paper describes the development of nucleic acid detection in paper using a combination of commercial fluorescent probes and DNA ladders, and provides us with a better understanding of the interactions between double-stranded DNA (the amplified products in this study), fiber structures in paper, and fluorescent probes. The amplified products (the reverse-transcription and amplification of d...

Genotyping and gene-expression monitoring is critical to the study of the association between genetics and drug response (pharmacogenomics) and the association of sequence variation with heritable phenotypes. Recently, we developed an entirely electronic method for the detection of DNA hybridization events by the site-specific incorporation of ferrocenyl derivatives into DNA oligonucleotides. T...