Here we describe a highly selective DNA-based electrochemical sensor that utilizes steric hindrance effects to signal the presence of large macromolecules in single-step procedure. We first show macromolecule, such as protein, when bound signaling DNA strand generates effects, which limits ability this hybridize surface-attached complementary strand. demonstrate efficiency hybridization is inversely correlated with size molecule attached it, following semilogarithmic relationship. Using...

A simple modified TiO(2) nanotubes electrode was fabricated by electrodeposition of Pd, Pt and Au nanoparticles. The prepared using the anodizing method, followed modifying Pd nanoparticles onto tubes surface, offering a uniform conductive surface for Au. performance characterized cyclic voltammetry differential pulse methods. Au/Pt/Pd/TiO(2) NTs represented high sensitivity towards individual detection dopamine as well simultaneous uric acid 0.1 M phosphate buffer solution (pH 7.00) base...

High-curvature electrodes facilitate rapid and sensitive detection of a broad class molecular analytes. These sensors have reached limits not attained using bulk macroscale materials. It has been proposed that immobilized DNA probes are displayed at high deflection angle on the sensor surface, which allows greater accessibility more efficient hybridization. Here we report first use all-atom dynamics simulations coupled with electrochemical experiments to explore single-stranded...

Hierarchical 3D gold nano-/microislands (NMIs) are favorably structured for direct and probe-free capture of bacteria in optical electrochemical sensors. Moreover, their unique plasmonic properties make them a suitable candidate plasmonic-assisted sensors, yet the charge transfer needs to be improved. In present study, we propose novel impedimetric detection platform based on hybrid structures NMIs graphene (Gr) nanosheets label-free bacteria. The inclusion Gr significantly improves...

The chalcogenide material MoS2 has been recognized as a promising candidate for photoelectrochemical (PEC) applications due to its enhanced photocatalytic and electrocatalytic activities. However, few reports have focused on the designated catalytic nonenzymatic PEC sensing of small molecules. Here, we report novel in situ fab-free method direct growth three-dimensional (3D) porous Peony-like nanosheets supported by nanohole-patterned TiO2 composited with gold deposits. resulted electrical...

Abstract Efficient capture and rapid detection of pathogenic bacteria from body fluids lead to early diagnostics bacterial infections significantly enhance the survival rate. We propose a universal nano/microfluidic device integrated with 3D nanostructured platform for sensitive quantifiable bacteria. Surface characterization confirms uniform distribution hierarchical nano‐/microisland (NMI) structures spatial orientation nanorough protrusions. The NMI is unique characteristic device, which...

The development of a universal sensing mechanism for the rapid and quantitative detection small molecules directly in whole blood would drastically impact global health by enabling disease diagnostics, monitoring, treatment at home. We have previously shown that hybridization between free DNA strand its complementary surface-bound can be sterically hindered when former is bound to large antibodies. Here, we exploit this effect design competitive antibody-based electrochemical assay, called...

Three-dimensional (3D) electrodes with large surface areas are highly effective biomolecular sensors. These structures can be generated via the electrodeposition of gold inside microscale apertures patterned on a microelectronic chip. Such enable ultrasensitive analysis nucleic acids, proteins, and small molecules. Since performance these is directly related to their area, ability control morphology critical. Here, we explore an electrochemical model based theory nucleation growth better...

The availability of rapid approaches for quantitative detection biomarkers would drastically impact global health by enabling decentralized disease diagnosis anywhere that patient care is administered. A promising new approach, the electrochemical steric hindrance hybridization assay (eSHHA) has been introduced large proteins (e.g., antibodies) with a low nanomolar limit within 10 min. Here, we report use nanostructured microelectrode (NME) platform eSHHA improves performance this approach...

Diagnosis of infectious disease in patients, including human immunodeficiency virus (HIV) infection, can be achieved through the detection specific antibodies produced by immune system. We have previously shown that macromolecules such as efficiently detected complex biological samples sterically inhibiting hybridization conjugated complementary DNA strands to electrode-bound strands. Here, we report a peptide-mediated electrochemical steric hindrance assay, PeSHHA, specially for against...

The ex vivo expansion of hematopoietic stem cells is significantly inhibited by secreted proteins that induce negative feedback loops. ability to effectively monitor these factors critical for their real-time regulation and control and, extension, enhancing cell expansion. Here, we describe a novel monitoring strategy the detection soluble signaling in cultures using DNA-based sensing mechanism on chip-based nanostructured microelectrode platform. We combine DNA hybridization engineering...

The present work describes sensing application of modified TiO2 nanotubes having carbon-Pt nanoparticles for simultaneous detection dopamine and uric acid. electrode was prepared using anodizing method, followed by electrodeposition Pt onto the tubes. Carbon deposited decomposition polyethylene glycol in a tube furnace to improve conductivity. C-Pt-TiO2 characterized cyclic voltammetry differential pulse methods. displayed high sensitivity towards oxidation acid phosphate buffer solution (pH...

Image-reversal soft lithography enables the straightforward fabrication of high-performance biosensors without requiringhigh-resolution photolitography.

TiO2 nanotubes electrode was fabricated by anodizing Ti sheets in Fcontained solution. The final modified then prepared electrochemical pulse deposition of Pd and Pt nanoparticles onto the surface tubes. morphological characterization suggested a uniform regular tubular structure which decorated metal nanoparticles. performance characterized cyclic voltammetry differential methods. Pt-Pd-TiO2 NTs represented relatively high sensitivity towards detection dopamine 0.1 M phosphate buffer...

Photoelectrochemical (PEC) sensing systems are promising candidates for detecting low concentrations of biological molecules; they particularly encouraging when offered in a non-enzymatic format. A pitfall PEC sensors is their specificity. This, however, often resolved by utilizing inorganic nanocatalyst. Here, we describe novel sunlight-driven sensor based on cobalt phosphate (Co-Pi) deposition one-dimensional titanium dioxide (1D-TiO2) nanorod array the ultra-low detection glucose. The...