Abstract: Described herein are methods and devices of detecting a particulate analyte in a sample solution, using an electrochemical cell having an anodic compartment and a cathodic compartment, wherein the anodic and cathodic compartments are separated by a semi-permeable membrane. The sample solution is acidified by applying a positive current to the anodic compartment and maintaining the positive current to permit anions to flow from the cathodic compartment to the anodic compartment through the semi-permeable membrane. The analyte is deposited on an electrode disposed in the anodic compartment by applying a negative current. The deposited analyte is stripped from the electrode and an electrochemical voltammogram is generated by measuring the current as the analyte is stripped from the electrodes. The voltammogram is used to determine the concentration of the analytes in the sample solution based on the generated electrochemical voltammogram.

Abstract: An electrode includes an insulating surface layer and at least one aligned carbon nanotube fiber embedded in the insulating surface layer. Each of the at least one aligned carbon nanotube fiber has a first end and a second end opposite the first end, and the first end and the second end are separated by a body. Each of the at least one aligned carbon nanotube fiber is composed of a plurality of carbon nanotubes. The first end and the second end are free of the insulating surface layer. The second end is in contact with an electrical conductive material. A method of analyzing an analyte in a sample and a device for energy storage using the electrode are also described.

Abstract: Described are sensors and methods of detecting hydrogen gas. The sensor includes a polymer matrix and a dye molecule in an amount sufficient such that exposure of the polymer matrix to hydrogen gas causes a change in a spectroscopic property of the dye molecule wherein the spectroscopic property includes at least one of color, absorbance, or luminescence. The polymer matrix may further include a catalyst, such as a transition metal, sulfonated Wilkinson's catalyst, colloidal Pt, sulfonated iridium cyclooctadiene triphenylphosphine, sulfonated rhodium cyclooctadiene triphenylphosphine, sulfonated ruthenium triphenylphosphine, or combinations thereof. Embodiments of the sensor may further include a gas permeable, water impermeable membrane, an outer covering, or combinations thereof.

Abstract: Described are sensors and methods of detecting hydrogen gas. The sensor includes a polymer matrix and a dye molecule in an amount sufficient such that exposure of the polymer matrix to hydrogen gas causes a change in a spectroscopic property of the dye molecule wherein the spectroscopic property includes at least one of color, absorbance, or luminescence. The polymer matrix may further include a catalyst, such as a transition metal, sulfonated Wilkinson's catalyst, colloidal Pt, sulfonated iridium cyclooctadiene triphenylphosphine, sulfonated rhodium cyclooctadiene triphenylphosphine, sulfonated ruthenium triphenylphosphine, or combinations thereof. Embodiments of the sensor may further include a gas permeable, water impermeable membrane, an outer covering, or combinations thereof.

Abstract: An apparatus and method of simultaneous spectroelectrochemical analysis is disclosed. A transparent surface is provided. An analyte solution on the transparent surface is contacted with a working electrode and at least one other electrode. Light from a light source is focused on either a surface of the working electrode or the analyte solution. The light reflected from either the surface of the working electrode or the analyte solution is detected. The potential of the working electrode is adjusted, and spectroscopic changes of the analyte solution that occur with changes in thermodynamic potentials are monitored.

Abstract: The present invention relates to methods for the detection of microorganisms. In one embodiment, the present invention provides methods for detecting live microorganisms in a culture by capturing and culting the microorganisms on para-tropic-coated paramagnetic beads. This technique is useful for any application in which it is necessary to monitor the biological contamination level, for example drinking water, recreational waters, food processing waters and medical laboratories. In one embodiment, the method for determining the concentration of viable microorganisms in a sample according to the invention further comprises an inducer reagent, wherein the inducer reagent includes an inducer compound that induces the activity of an enzyme unique to the microorganism of interest.

Abstract: A simultaneous multianalyte electrochemical assay includes a cell which has a surface and the surface includes analyte binding sites i.e., antibodies or antigens on a solid phase at distinct separate locations. Separate working electrodes are located within proximity to these separate locations. Enzyme labeled antibodies or antigens depending on the assay format are added and the enzyme reaction product measured, by simultaneous amperometric measurement with the independent electrode in each area. The electrodes are spatially separated from adjacent analytes so that a measurement can be taken before cross-interference due to diffusion of product from adjacent analyte areas.

Abstract: An apparatus 20 for the separation of a subpopulation of cells from an intact organ or other biological material is provided. The apparatus 20 includes: (1) a digestion chamber 24 that integrates the primary digestion process, (2) a measuring cylinder 26, (3) a cell collection chamber 28, (4) a heat exchanger 30 for raising and lowering temperatures in the digestion chamber 24 to activate or inactivate enzymes, (5) sensors 112, 114, 116, 118, 120, 122 to complete a closed feedback loop for allowing optimization of the digestion process, and (6) mock cells which mimic the cells to be harvested and which are used to fully optimize the process without unnecessary destruction of harvested cells. The manipulation of the digestion process may be manual or may be automated under computer control.

Abstract: The present invention is premised on the realization that a single electrochemical binding assay device can be used to determine multiple analytes in a single sample by simultaneous amperometric measurements using a plurality of working electrodes.

Abstract: The concentration of NADH or NADPH in a test solution is determined by adding a redox coupling agent, preferably 2,6 dichloroindophenol DCIP, to the test solution. The coupling agent reacts with the NADH or NADPH to form an electroactive coupling agent (DCIPH.sub.2) which is then detected electrochemically at a lower voltage than would be required to detect the NADH or NADPH. This can be used to detect NADH or NADPH formed by any well known enzymatic or immunoassay method which produces NADH as a detectable product. This has particular application to biological fluids such as whole blood which does not require any treatment of the test sample prior to electrochemical analysis. In particular, red blood cells do not have to be removed from whole blood samples to provide reliable data.

Abstract: An electrode having a coating comprising at least two layers, at least one layer being a polymer network cross-linked by high energy radiation or chemically, and a method of producing such an electrode. The electrode is useful as a sensor for molecular oxygen, or as an ampermometric sensor with an enzyme or antibody immobilized in the cross-linked polymer layer.