Recently, considerable interest and effort have been devoted to the on-site detection of low-concentration pathogenic bacteria in order to deter infectious diseases and bioterrorism. Conventionally, bacteria detection involves culturing, which is time-consuming and unfeasible under field conditions. Microfluidic devices with integrated electrical detection will enable fast, low-cost, and portab...

Carbon nanotubes have been explored as interconnects in solid acid fuel cells to improve the link between nanoscale Pt catalyst particles and macroscale current collectors. The nanotubes were grown by chemical vapor deposition on carbon paper substrates, using nickel nanoparticles as the catalyst, and were characterized using scanning electron microscopy and Raman spectroscopy. The composite el...

Microfludic devices with integrated electrical detection will enable fast, low-cost or portable sensing and processing of biological and chemical samples. As an inherent property of microfabrication, microelectrical impedance spectroscopy detectors can take advantage of AC electrokinetics for particle manipulation, leading to enhanced sensitivity. Preliminary experiments on particle detection w...

Common impedance methods in tissues or cell suspensions as well as dielectric particle spectroscopy by ACelectrokinetics are based on the impedance properties of the different constituents of tissue, particles or cells and the suspensionmedia.Whereas impedancemethods detect the frequency dependence of the direct electric response of a suspension, electrokinetic methods investigate the frequency...

A Polyaniline/Manganese dioxide (PANI/MnO2) nanocomposite contains five weight percentages of MnO2. It has been successfully prepared by in situ polymerization. The structural, optical, and conductivity of nanocomposites remain relative to changes with respect to the weight percentage of MnO2. The structural, morphological, optical, and electrical conductivity i...

Second harmonic ac impedance and differential photocurrent techniques are employed to monitor, in situ, the surface states on n-MoSes electrodes in aqueous solutions containing the Fe(CN)6 s-/4couple. These two techniques are qualitatively more sensitive to the presence of surface states on single-crystal n-MoSes than first harmonic ac techniques. Surface states on this semiconductor electrode ...

Impedance spectroscopy has long been recognized as one of the major techniques for the characterization of ac transport in materials. The primary limitation of this technique is the lack of spatial resolution that precludes the equivalent circuit elements from being unambiguously associated with individual microstructural features. Here we present a scanning probe microscopy technique for quant...