An electrode for use in instruments capable of measuring the electrophoretic mobility of particles in solution is disclosed. The electrode is comprised of an inexpensive support member, generally made of titanium, onto a flat surface of which has been connected, generally by microwelding, a flat electrically conductive but chemically inert foil member, preferably platinum. A uniform texture can be generated on the exposed surfaces of the electrode by various means including tumbling the electrode with an abrasive. An oxide layer can be generated on the support member by soaking the composite electrode in an appropriate medium, protecting the exposed surface of the support member from fluid contact with the sample solution, while the foil member, unaffected by the oxidation process, is able to contact the sample solution.

Embodiments herein relate to breath analysis system. In an embodiment, a gas measurement device is included having a housing defining an interior volume. The housing can include a fluid ingress port, a fluid egress port, a bottom wall, and a circuit board disposed within the interior volume. The circuit board can include a first side and a second side, where the first side of the circuit board faces inward toward the interior volume. The circuit board can include a plurality of gas sensors disposed on the first side of the circuit board and a plurality of conductive pads disposed on the second side of the circuit board, wherein a plurality of electrical contacts contact the conductive pads when the circuit board is seated within the housing. Other embodiments are also included herein.

Provided is the processing of sample fluids containing one or more analytes of interest and to methods and devices for separating and/or purifying components of a sample fluid using electric and hydrodynamic forces. Though the fluid processing systems and methods are generally described herein as applied to microfluidics, it will be appreciated that the fluid processing systems may process any fluid volume suitable for use in embodiments described herein. Y-shaped and multiple-branched shaped 2-D EFD devices have been used to separate and/or purify one or more analytes from a mixture. Systems and methods in accordance with various aspects of the present teachings utilize hydrodynamic pressure (e.g., using a pump) to drive the sample liquid from the sample inlet to the separation stream, and can, in some aspects, provide improved control of the movement of the analytes, improved processing times, and decreased buffer depletion.

An ITP-based system and a method are provided. ITP is used to focus a sample of interest and deliver a high concentration target to a pre-functionalized surface comprising immobilized probes, thus enabling rapid reaction at the sensor site.

Isotachophoresis (ITP) is exploited to control various aspects of chemical reactions. In a first aspect, at least one of the reactants of a chemical reaction is confined to an ITP zone, but the resulting product of the chemical reaction is separated from this ITP zone by the ITP process. In a second aspect, one or more reactants of a chemical reaction are confined to an ITP zone, and one or more other reactants of the chemical reaction are not confined to this ITP zone. In a third aspect, ITP is employed to confine at least one reactant of a chemical reaction to an ITP zone, and at least one reactant of the chemical reaction is delivered to the ITP zone in two or more discrete doses. These aspects are especially relevant to performing polymerase chain reactions using chemical denaturants as opposed to thermal cycling.

An electrode for use in instruments capable of measuring the electrophoretic mobility of particles in solution is disclosed. The electrode is comprised of an inexpensive support member, generally made of titanium, onto a flat surface of which has been connected, generally by microwelding, a flat electrically conductive but chemically inert foil member, preferably platinum. A uniform texture can be generated on the exposed surfaces of the electrode by various means including tumbling the electrode with an abrasive. An oxide layer can be generated on the support member by soaking the composite electrode in an appropriate medium, protecting the exposed surface of the support member from fluid contact with the sample solution, while the foil member, unaffected by the oxidation process, is able to contact the sample solution.

An electrode for use in instruments capable of measuring the electrophoretic mobility of particles in solution is disclosed. The electrode is comprised of an inexpensive support member, generally made of titanium, onto a flat surface of which has been connected, generally by microwelding, a flat electrically conductive but chemically inert foil member, preferably platinum. A uniform texture can be generated on the exposed surfaces of the electrode by various means including tumbling the electrode with an abrasive. An oxide layer can be generated on the support member by soaking the composite electrode in an appropriate medium, protecting the exposed surface of the support member from fluid contact with the sample solution, while the foil member, unaffected by the oxidation process, is able to contact the sample solution.

A system comprising a protein and a channel. The channel has a domain that binds a membranal component. The channel is configured to carry a liquid sample to an isotachophoresis (ITP) apparatus. The liquid sample comprising or suspected of comprising a cell, a cell membrane or a fraction of a cell membrane. The ITP apparatus comprises a first zone and a second zone. The first zone is configured to contain a solution of high effective mobility leading electrolyte (LE) ion. The second zone is configured to contain a solution of low effective mobility trailing electrolyte (TE) ion. The first zone and the second zone are configured to be operably connected to at least one anode and at least one cathode.

Embodiments herein relate to breath analysis system. In an embodiment, a gas measurement device is included having a housing defining an interior volume. The housing can include a fluid ingress port, a fluid egress port, a bottom wall, and a circuit board disposed within the interior volume. The circuit board can include a first side and a second side, where the first side of the circuit board faces inward toward the interior volume. The circuit board can include a plurality of gas sensors disposed on the first side of the circuit board and a plurality of conductive pads disposed on the second side of the circuit board, wherein a plurality of electrical contacts contact the conductive pads when the circuit board is seated within the housing. Other embodiments are also included herein.

A method for sequence-specifically detecting a nucleic acid molecule. The method requires: a) contacting in an absence of an electric field, a mixture of nucleic acid molecules with a base pairing hybridizing molecule (BPHM) having a sequence of interest in a first solution and obtaining a hybrid consisting the nucleic acid molecule and the BPHM; b) introducing the first solution from step (a) into an ITP system, the ITP system comprises a second solution of high effective mobility leading electrolyte (LE) ions and a third solution of low effective mobility trailing electrolyte (TE); and c) applying the electric field across the second solution and the third solution. The hybrid focus at the sharp LE-TE interface in the ITP system. The TE has a higher mobility than the BPHM and the TE has a lower mobility than the hybrid. Sequence-specifically the detecting nucleic acid molecule by a signal from a label.