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...

We present here the construction of a DNA biosensor based on a tubular micromotor that only produces motion-based signal in the presence of DNA target. This "turn on" characteristic of the sensor is achieved by the addition of Pt nanoparticle-DNA conjugate as the motion-inducing catalyst for the micromotors through DNA hybridization. Our work potentially offers new design strategies for motion-...

A novel conductive DNA-based nanomaterial, DNA-peptide wire, composed of a DNA core and a peripheral peptide layer, is presented. The electrical conductivity of the wire is found to be at least three orders in magnitude higher than that of native double-stranded DNA (dsDNA). High conductivity of the wires along with a better resistance to mechanical deformations caused by interactions between t...

Adriamycin, a cancerostatic anthracycline antibiotic, causes considerable death of tumour cells, together with the induction of breaks in DNA single and double strands. The interaction of this compound with DNA was investigated using an electrochemical DNA-biosensor. Adriamycin intercalation in DNA disrupts the double helix and the detection of guanine and 8-oxoguanine could mimic one possible ...

In this study, a new universal biosensor based on luminol anodic electrochemiluminescence (ECL) for the detection of microRNA-155 was constructed by using hydrogen peroxide (H2O2) as a co-reactant and hemin as a catalyzer for signal amplification. The bare glassy carbon electrode (GCE) was first electrodeposited with Au nanoparticles (AuNPs). Then, helper DNA, which was partly complementary wit...

A label-free fluorescent DNA biosensor has been presented based on isothermal circular strand-displacement polymerization reaction (ICSDPR) combined with graphene oxide (GO) binding. The proposed method is simple and cost-effective with a low detection limit of 4 pM, which compares favorably with other GO-based homogenous DNA detection methods.