We report the picosecond and nanosecond timescale rotational dynamics of a dye-labeled DNA oligonucleotide or "aptamer" designed to bind specifically to immunoglobulin E. Rotational dynamics in combination with fluorescence lifetime measurements provide information about dye-DNA interactions. Comparison of Texas Red (TR), fluorescein, and tetramethylrhodamine (TAMRA)-labeled aptamers reveals su...

We report on a novel strategy for DNA aptamer immobilization to develop sensitive electrochemical detection of a protein biomarker, with prostate specific antigen (PSA) as a case biomarker. Thiolated single-stranded DNA (ssDNA) was co-immobilized with 3-mercapto-1-propanol on gold electrodes, and used as a scaffold for DNA aptamer attachment through hybridization of the aptamer overhang (so-cal...

Here, we used a fluorophore-bound, porphyrin-targeted DNA aptamer to increase the sensitivity of capillary electrophoresis for detection model porphyrin. The complex wit...

Aptamers are single-stranded nucleic acids with defined tertiary structures for selective binding to target molecules. Aptamers are also able to bind a complementary DNA sequence to form a duplex structure. In this report, we describe a strategy for designing aptamer-based fluorescent reporters that function by switching structures from DNA/DNA duplex to DNA/target complex. The duplex is formed...

We proposed a new three-way DNA junction-driven strand displacement mode and fabricated an aptamer-based label-free fluorescent sensing platform on the basis of this mechanism. Assembling the aptamer sequence into the three-way DNA junction makes the platform sensitive to the target of the aptamer. A label-free signal readout method, split G-quadruplex enhanced fluorescence of protoporphyrin IX...

This study describes the fabrication techniques for two forms of magnetic DNA nanotubes (MDNTs) and their applications as platforms for developing colorimetric assays. The first form of MDNTs was DNTs filled-up with magnetic nanoparticles (MNPs) and the second one was DNTs arayed with MNPs on their extrior surfaces. Then the both forms of MDNTs were employed as platforms for attaching a specifi...

BACKGROUND DNA aptamers are single-stranded nucleotide sequences that bind specifically to target molecules. By combining the advantages of PCR for amplifying specific DNA sequences and aptamer technology, we have developed a new strategy to detect target molecules such as proteins. METHODS Ovine follicle-stimulating hormone alpha subunit (oFSHalpha) was used as the model protein to generate ...

Combining gold nanoparticles (GNPs) as fluorescence quencher and aptamer as probe, we have developed protein biosensors by using DNA-modified GNPs. We examined how the experimental design, such as the type of interaction between DNA strands and GNPs, temperature, and microenvironment of aptamer, influences the recognition ability of the biosensor. Under our experimental conditions, the recognit...

The self-assembly of single-stranded DNA (ssDNA) aptamer-amphiphiles was influenced by the choice of spacer used to link the hydrophobic tail and aptamer headgroup. Aptamer-amphiphiles without spacers or with hydrophilic spacers formed globular micelles while amphiphiles with hydrophobic spacers formed bilayer nanotapes, which are the first such structures formed by DNA-amphiphiles.

Aptamer fonksiyonlandırılmış DNA hidrojelleri yüksek özgünlük, stabilite ve esneklik gibi özellikleri nedeniyle birçok alanda kullanılmaktadır. Bu çalışma kapsamında kloramfenikole özgü aptamer dizisi hidrojeli sentezi gerçekleştirilmiş hidrojel stabilitesi için önemli parametreler optimize edilmiştir. Sentez 5’ uçları akridit modifiyeli ile ona kısmen eşlenik ipliği polimer yapıya yan dal olar...