Herein, a label-free fluorescent adenosine triphosphate (ATP) aptasensor is fabricated with a DNA hairpin and an overhanging aptamer. In the presence of ATP, the overhanging sequences of the aptamer may form preferred substrates of exo III, and thus trigger the enzyme-assisted amplification, which results in the release of G-rich sequences. Free G-rich sequences subsequently generate an enhance...

A novel label-free electrochemical nucleic acid aptasensor for the determination of cocaine by the immobilization of thiolated self-assembled DNA sequences on a gold nanoparticles-modified electrode is presented. When cocaine was complexed specifically to the aptamer, the configuration of the nucleic acid aptamer switched to a locked structure and the interface of the biosensor changed, resulti...

Quantifying the glycan expression status on cell surfaces is of vital importance for insight into the glycan function in biological processes and related diseases. Here we developed a versatile aptasensor for electrochemical quantification of cell surface glycan by taking advantage of the cell-specific aptamer, and the lectin-functionalized gold nanoparticles acting as both a glycan recognition...

Using an acoustic method we showed that the aptamer configuration, especially those comprised of dimers with binding exosites sensitive to heparin and fibrinogen at thrombin, substantially increases the aptasensor sensitivity.

We report the first use of an electrochemical aptasensor for selective potassium recognition, based on a conformational change, affording an electric signal transduced electrochemically by square wave voltammetry or electrochemical impedance spectroscopy.

For the first time, hemin/G-quadruplex was employed to simultaneously serve as NADH oxidase and an HRP-mimicking DNAzyme for constructing a simple and sensitive pseudobienzyme-amplifying electrochemical aptasensor for thrombin detection.

A novel permeability gate-based electrochemiluminescent (ECL) aptasensor has been constructed by utilizing target-responsive polyelectrolyte-aptamer film deposited on the solid-state ECL electrode to control the rate of diffusion of a coreactant that triggers the ECL.

We designed a novel aptamer based biosensor (aptasensor) for ultrasensitive detection of adenosine triphosphate (ATP) through resonance energy transfer (RET). The ATP aptamer was modified with Cy3 at the 3' end, and a green quantum dot (525) was attached to the 5' end of its complementary sequence respectively. The ATP aptamer and its complementary sequence could assemble into a duplex structur...

A label-free fluorescence aptasensor for highly selective and sensitive detection of ATP and thrombin was developed by using PicoGreen (PG) as signal molecule and surface-bound metal-enhanced fluorescence (MEF) substrates (silver island films, SIFs) as signal enhancers. On binding with ATP or thrombin, aptamers undergo structure switching, leading to a reduction of fluorescence intensity of PG....

a label-free electrochemical nucleic acid aptasensor for the detection of methamphetamine (ma) by the immobilization of thiolated self-assembled dna sequences on a gold nanoparticles-chitosan modified electrode is constructed. when ma was complexed specifically to the aptamer, the configuration of the nucleic acid aptamer switched to a locked structure and the interface of the biosensor changed...