Abstract: A system for recycling helium carrier gas comprises: a bladder, the bladder interior fluidically configured so as to receive helium-bearing gas output from at least one of a split vent and a septum purge vent of a gas chromatograph; a compartment containing the bladder; a source of pressurized air or gas operable so as to supply pressurized air or gas into the compartment interior so as to compress the bladder containing the helium-bearing gas; a gas reservoir fluidically coupled to the bladder interior so as to receive the helium bearing gas from the compressed bladder interior; and at least one gas purification module configured so as to receive the helium-bearing gas from the gas reservoir and operable to remove contaminants from the helium-bearing gas, an output of the at least one gas purification module being fluidically coupled to a carrier gas inlet of the gas chromatograph.

Abstract: Certain embodiments described herein are directed to chromatography systems that include a microfluidic device. The microfluidic device can be fluidically coupled to a switching valve to provide for selective control of fluid flow in the chromatography system. In some examples, the microfluidic device may include a charging chamber, a bypass restrictor or other features that can provide for added control of the fluid flow in the system. Methods of using the devices and methods of calculating lengths and diameters to provide a desired flow rate are also described.

Abstract: Methods and apparatuses for chromatography are provided, using, for example, water as a stationary phase and carbon dioxide as the mobile phase.

Abstract: A thermal modulation device for a gas chromatography (GC) system a cold zone, a first hot zone and a second hot zone, which are located outside of a GC oven of the GC system, and a flexible capillary column. The cold zone includes a thermoelectric cooler assembly. The first hot zone is adjacent a first side of the cold zone, and has a corresponding first heat source. The second hot zone is adjacent a second side of the cold zone, and has a corresponding second heat source. The flexible capillary column includes a first segment, configured to move between the first hot zone and the cold zone in accordance with a modulation frequency, and a second segment, configured to move between the cold zone and the second hot zone in accordance with the modulation frequency.

Abstract: The present invention is directed to a method for multidimensional gas chromatography for separating the analytes of a complex sample. The method comprises the steps of introducing the sample onto a first column whereby the sample is separated into at least two segments, introducing at least one segment into a heartcut device whereby the segments are selectively separated into at least two heartcut fractions, introducing at least one of the fractions onto a second column whereby at least one fraction is further separated into at least two analytes, introducing at least one analyte from the second column to a gas chromatography connector, introducing the analyte from the connector to a third column, and introducing the analyte from the third column into a detector whereby the analyte is analyzed and identified.

Abstract: Methods for depositing a stationary phase in a tube for chromatography, in particular, as a variable gradient column are disclosed. The methods include providing a tube having a first end and a second end, the tube containing a fluid composition comprising a stationary phase precursor and a solvent, connecting the first end of the tube to a flow device, removing the solvent from a meniscus of the fluid composition, the solvent exiting the tube at the second end, and operating the flow device while removing the solvent such that the amount of the stationary phase precursor deposited within the tube changes as the meniscus retreats within the tube to deposit a stationary phase having a thickness gradient along the length of the interior of the tube.

Abstract: An apparatus, according to one aspect, may include a chromatograph and a bulk acoustic resonator. The chromatograph may include a channel that is defined at least partially in a monolithic substrate. The channel may have an inlet to receive a sample and an outlet. A chromatography material may be included in the channel. The bulk acoustic resonator may have a first electrode and a second electrode that has a chemically functionalized surface. The chemically functionalized surface may be included in a chamber that is defined at least partially in the monolithic substrate and that is coupled with the outlet of the channel. Methods of making and using such apparatus, and systems including such apparatus, are also disclosed.

Abstract: Systems and methods for cooling a chromatographic column is disclosed generally, comprising heating a chromatographic column, supplying fluid into the column via the inlet end of the column at an inlet pressure, decreasing the temperature of the column, thereby causing the fluid in the column to contract, and controlling the fluid in the column such that the rate at which the fluid in the column contracts does not exceed the flow rate of the fluid supplied to the column. In certain embodiments, the rate of change of the volume of the fluid in the column as the column temperature decreases is modeled, and the rate of contraction of the gas in the column is estimated therefrom. In some embodiments, the column temperature and/or inlet pressure are controlled by a programmable chromatographic oven.

Abstract: A method for the superficial-phase chromatography of a product comprises the steps which are performed continuously in the following order, namely: an operation consisting in pumping a supercritical fluid; and operation consisting of injecting at least one sample of product into at least one chromatography column, a detection operation, and a fraction collection operation. The method comprises at least a first diversion along between an analytical channel and a preparatory channel, which diversion is performed prior to the supercritical fluid pumping operation and the analytical and preparatory channels each including respective supercritical fluid pumping operations. The method is also characterized in that the collection operation is common to both the analytical and preparatory channels. An installation used to implement one such method is described.

Abstract: Improved microcolumns and methods for producing microcolumns particularly suitable for use in gas chromatographs are disclosed. In particular, following deposition of the stationary phase coating, the microcolumns are subjected to a postcoating treatment with a molecule that binds to the active sites in the stationary phase column thereby eliminating or reducing loss of gas chromatograph performance associated with those active sites. The postcoating treatment molecule binds to the same active sites as the analytes of interest.

Abstract: An apparatus, system, and method are disclosed for a gas chromatography (GC) system with a check valve. The check valve is situated downstream from the electronic flow control module and upstream of the injector. When a sample is volatized in the injector, the check valve closes into a checked position and prevents solvent and sample from backing into the gas delivery line. In certain embodiments, the check valve has a conical plug that fits into a seat that has an aperture. When the conical plug is depressed, the conical plug engages the sides of the aperture and seals the check valve, preventing solvent and sample from backing through the check valve. In certain embodiments, the change in pressure caused by over-pressurization in the injector, combined with the force applied by a spring on the conical plug, depresses the plug such that it seals the aperture.

Abstract: The present invention is generally directed to a microfabricated gas chromatograph column having two patterned substrates, each optionally having a stationary phase material coating, bonded together to provide a continuous flow channel. The flow channel can have a serpentine arrangement or a modified serpentine arrangement comprising alternating series of consecutive turns in one direction where each series has enough turns to move carrier gas and analyte molecules from the center of the column cross section to an outer wall of the channel or from one outer wall of the channel to the opposite outer wall. Different portions of the substrates can be coated with differing thicknesses of stationary phase material and/or with different stationary phase materials. The column can have a circular cross-section or a semi-circular cross-section where the flat portion of the cross-section has grooves. Also disclosed is the related method of making the microfabricated gas chromatograph column.

Abstract: Methods and related systems are described for improving component separations in chromatography through novel techniques. The improvements in separation is due primarily to the provision of differential acceleration of the components being separated. Various systems and methods for providing differential acceleration are described including: increasing the cross section of the column towards the column outlet, changing the thickness or other composition of stationary phase within the column, and providing a temperature and/or mobile phase velocity gradient along the column.

Abstract: Improved micro-columns and methods for producing micro-columns particularly suitable for use in gas chromatographs are disclosed. In particular, following deposition of the stationary phase coating, the micro-columns are subjected to a postcoating treatment with a molecule that binds to the active sites in the stationary phase micro-column thereby eliminating or reducing loss of gas chromatograph performance associated with those active sites. The postcoating treatment molecule binds to the same active sites as the analytes of interest.

Abstract: A portable multi-dimensional gas chromatograph, the gas chromatograph including a carrier gas container, a regulator fluidly connected to the carrier gas container, a dopant chamber containing a reference chemical, at least one pre-concentrator which is fluidly connected to the regulator and the dopant chamber, a first separation column fluidly connected to the at least one pre-concentrator, a second separation column fluidly connected to the at least one pre-concentrator, a first detector fluidly connected to the first separation column, and a second detector fluidly connected to the second separation column.

Abstract: The present invention provides sol-gel germania-coated chromatography separation columns with improved stability under extreme pHs and high temperatures. Also provided are methods of preparation and uses of the sol-gel germania-coated separation columns of the present invention.

Abstract: A gas adsorbing column filled with a filler composed of an adsorbent supported on a substrate having an average particle size or cross-sectional average diameter of 500 ?m to 1000 ?m, wherein the void volume of the column is 5 to 100 ?l.

Abstract: An apparatus and a method of making a measurement using the same. The apparatus includes a channel through which a fluid flows, a detector, and a choked flow channel. The detector measures a property of the fluid by generating a signal that depends on that property. The signal generated also depends on a pressure of the fluid in the detector. The choked flow channel receives the fluid at a first pressure after the fluid has been measured by the detector, and then transmits the fluid to a downstream location at a second pressure. The fluid reaches a supersonic velocity at one point in the choked flow channel. The choked flow channel may include a convergent-divergent nozzle or an orifice in a structure located in the choked flow channel.

Abstract: The present invention provides germania-silica-based sol-gel monoliths that form the solid-phase material for extraction, isolation, preconcentration, and separation of analytes. In one embodiment, the germania-silica-based sol-gel monolith can be used to coat surfaces of the inner walls of extraction and chromatographic columns. In a preferred embodiment, the sol-gel germania-silica monolith of the present invention is formed from hydrolysis and polycondensation of precursors comprising tetraethoxygermane, tetramethoxysilane, and polyethylene glycol. Also provided are methods of preparing the germania-silica-based sol-gel monolith of the present invention.

Abstract: A method and apparatus for the in-situ, chemical analysis of an aerosol. The method may include the steps of: collecting an aerosol; thermally desorbing the aerosol into a carrier gas to provide desorbed aerosol material; transporting the desorbed aerosol material onto the head of a gas chromatography column; analyzing the aerosol material using a gas chromatograph, and quantizing the aerosol material as it evolves from the gas chromatography column. The apparatus includes a collection and thermal desorption cell, a gas chromatograph including a gas chromatography column, heated transport lines coupling the cell and the column; and a quantization detector for aerosol material evolving from the gas chromatography column.

Abstract: A microtrap assembly includes a carbon nanotube sorbent. The microtrap assembly may be employed as a preconcentrator operable to deliver a sample to an analytical device to measure the concentrations of greenhouse gases. A system includes a microtrap having a carbon nanotube sorbent for measuring the concentrations of greenhouse gases in a sample.

Abstract: A gas chromatograph oven including a housing, a capillary tube and a thermal control assembly. The housing defining a capillary tube receiving space and having at least one outlet port to permit the passage of a fluid from the capillary tube receiving space of the housing. The capillary tube is positioned in the capillary tube receiving space of the housing and has a gas inlet end connectable to a gas injector and a gas detector end connectable to a gas detector. The thermal control assembly is in fluid communication with the capillary tube receiving space of the housing and is connectable to a source of a temperature regulating fluid.

Abstract: Provided is a frit having a body comprising a matrix material, and a plurality of microcapillaries formed within the matrix material, the microcapillaries substantially aligned with a longitudinal axis of the body. The frit may comprise a microstructured fibre, such as a photonic crystal fibre. The fit may be coupled to a fluidic conduit such as a chromatography column and/or a nanoelectrospray emitter. The frit may be used in applications such as solid phase extraction, electrospray ionization mass spectrometry, microreactor systems, and filtering particles in any fluid system where there is a need to retain particles.

Abstract: A multicapillary column especially useful for liquid chromatography and sample preparation comprising a plurality of uniform capillaries coated with an insoluble stationary phase, wherein the thickness of the stationary phase is correlated with the radius of the individual capillaries for high efficiency.

Abstract: A process and sensor device are disclosed that employ metal ?-diketonate polymers to selectively capture gas-phase explosives and weaponized chemical agents in a sampling area or volume. The metal ?-diketonate polymers can be applied to surfaces in various analytical formats for detection of: improvised explosive devices, unexploded ordinance, munitions hidden in cargo holds, explosives, and chemical weapons in public areas.

Abstract: The present invention is directed to a field-mounted analyzer having a graphical user interface (GUI). The analyzer has a display screen visible from the exterior of the housing. A plurality of magnetically-actuatable switches are mounted behind the display screen. The GUI has a plurality of windows that may be displayed on the display screen. Navigation through the windows is accomplished by activating switches aligned with graphical navigation icons in the windows.

Abstract: An open probe method for sample introduction into a mass spectrometer is disclosed, comprising the steps of: loading a sample holder with sample compounds to be analyzed; heating a probe oven; introducing said sample compounds in said sample holder into said heated probe oven; flowing inert gas into said heated probe oven; vaporizing said sample in said heated probe oven by the combined effect of oven temperature and inert gas flow; entraining said vaporized sample in said inert gas; and, transferring said vaporized sample in inert gas into an ion source of a mass spectrometer; wherein said heated probe oven remains open to the ambient atmosphere during sample introduction and analysis; said inert gas is flowing in said heated probe oven in two directions of a transfer line to a mass spectrometer ion source and to the oven opening; said vaporized sample in inert gas is transferred through a heated transfer line directly into the ionization chamber of an ion source of a mass spectrometer.

Abstract: A compliant column sheath assembly for use in a gas chromatograph is provided which includes an open tubular column in the form of a helical coil having a coiled length of between about 5 and 15 cm. The sheath assembly further includes an insulating sheath which surrounds the open tubular column and a frame. When incorporated in a gas chromatograph, the compliant column sheath assembly allows samples to be analyzed in about 2 to 10 seconds.

Abstract: A chromatography column comprising a chromatography tube, a piston tube with a porous obstruction that inhibits the movement of particle solids therethrough, and a quick connect/disconnect clamp for use in coupling the chromatography tube to the piston tube. This column is for use in a liquid chromatography process where fluid is pumped under pressure through the chromatography tube which contains a packed particulate solid. The clamp allows for the quick removal and replacement of chromatography tubes when the particulate needs replacement.

Abstract: Embodiments of the present invention are directed to devices and methods for receiving NSC Fluids having at least one analyte from a chromatograph and directing analyte ions into the vacuum regions of a mass spectrometer. The device has a housing having at least one wall defining a chamber, sample inlet, an ionization media inlet and an outlet. The sample inlet has a position in communication with a chromatograph receiving a NSC Fluid. The sample inlet receives the NSC Fluid and directs the NSC Fluid into the chamber to form a sample jet of NSC Fluid. The ionization media inlet is placed in fluid communication with a source of ionization media and directs the ionization media into the chamber and the sample jet to create analyte ions. The analyte ions are received in the mass spectrometer vacuum region orifice.

Abstract: An apparatus and a method for separating a specified gas from a gas to be treated containing the specified gas comprising at least one ingredient, which comprises allowing the gas to be treated to flow through a column without the use of another gas for transferring the gas to be treated, while keeping the inside of the column packed with a packing material at a reduced pressure. The above apparatus and method can be suitably used for separating a specified gas having a high purity at a low cost.

Abstract: A gas chromatographic device comprises an inlet system and a chromatography column. The inlet system includes a liner having pressure reducing means contained therein for reducing pressure between an inlet of the pressure reducing means and an outlet of the pressure reducing means. When the devise is in use, the chromatography column is positioned in the liner of the inlet system downstream from the pressure reducing means, and the chromatography column is under vacuum at its outlet.

Abstract: A portable weather resistant gas chromatograph system with a gas chromatograph enclosure having a body and a movable door and a seal, a gas chromatograph with a frame assembly removably secured in the enclosure, a plurality of exhaust gas lines connected to the gas chromatograph, an explosion proof terminal box with circuit breakers and terminals mounted to the enclosure, a communication conduit and armored power cable between the explosion proof terminal box and the gas chromatograph, a purge gas conduit port for the gas chromatograph, a pedestal for the enclosure, and at least two lifting eyes connected to the enclosure.

Abstract: The present invention provides a chromatographic method for eliminating interference from interfering agents, coming from the gas sample itself or from the system material used to perform the impurities measurements, on impurities to be quantified in a gas sample. The method advantageously relies on the use of an additional valve and an additional sample loop particularly arranged in a G. C. system, and also on an additional supporting gas inlet operatively connected to the system through the additional sample loop for providing the system with a supporting gas comprising at least a predetermined portion of a predetermined active gas that will react with the unwanted interfering impurities, if any, or with the column material to cancel out unwanted active sites. Thus, the method of the present invention can advantageously be used in gas chromatographic systems to improve sensitivity thereof by acting on column separation material.

Abstract: The present invention is directed to a method for multidimensional gas chromatography for separating the analytes of a complex sample. The method comprises the steps of introducing the sample onto a first column whereby the sample is separated into at least two segments, introducing at least one segment into a heartcut device whereby the segments are selectively separated into at least two heartcut fractions, introducing at least one of the fractions onto a second column whereby at least one fraction is further separated into at least two analytes, introducing at least one analyte from the second column to a gas chromatography connector, introducing the analyte from the connector to a third column, and introducing the analyte from the third column into a detector whereby the analyte is analyzed and identified.

Abstract: An instrument and associated method are disclosed for preparing samples for column chromatography.

Abstract: The present invention relates to a chromatography column that removes the longitudinal load from the column tube altogether and transfers it to a yoke and stanchion arrangement situated around but external to the column tube. By using the yoke/stanchion system, the central adjuster can be used to move the top end into and out of the housing. Thus, when internal pressure is applied to the column, the tube experiences no longitudinal load. Additionally, the yoke and stanchion design allows for complete removal of the end from the tube without cumbersome disassembly. Moreover, the yoke provides a place to retain the end while the tube is being filled, emptied, cleaned or repaired.

Abstract: The present invention is directed to an enhanced sampling device, herein referred to as an ESD, for enhancing the collection efficiency of the SPME method by enhancing the flow of the analytes onto the sampling fiber. The ESD includes a tubular main body, used for a sampling shroud, which directs a flow of analytes to contact the fiber during collection. One end of the main body is open and faces the sample, allowing analytes to flow into the ESD and contact the fiber. A second piece of tubing branches from the other end of the main body and becomes an outlet port, possibly leading to a pump. The ESD permits more rapid transport and absorption of the analytes to the fiber for collection.

Abstract: An apparatus, according to one aspect, may include a chromatograph and a bulk acoustic resonator. The chromatograph may include a channel that is defined at least partially in a monolithic substrate. The channel may have an inlet to receive a sample and an outlet. A chromatography material may be included in the channel. The bulk acoustic resonator may have a first electrode and a second electrode that has a chemically functionalized surface. The chemically functionalized surface may be included in a chamber that is defined at least partially in the monolithic substrate and that is coupled with the outlet of the channel. Methods of making and using such apparatus, and systems including such apparatus, are also disclosed.

Abstract: The invention relates to an interface injector device for the direct coupling of liquid chromatography and gas chromatography, comprising an outer body (1) with an inner cavity with two inner chambers (2a, 2b) separated by a dividing element (9, 11a); a first passage (3) of the first chamber (2a) to a waste duct (8); an inner tube (5) arranged in the inner cavity and traversing the dividing element (9, 11a), and having a first section (5a) in the first inner chamber (2a), a second section (5b) in the second inner chamber (2b), and an inner channel (5f) which can house an adsorbent material (6), and at least one inorganic wool material (7) retained in the first section (5a) of the inner tube by retaining means (7), a first opening (10) communicated with the waste duct (8) exclusively through the first inner chamber (2a).

Abstract: One aspect of the invention relates to fluid-phase separators and devices containing them. Another aspect of the invention relates to the use of said fluid-phase separators and devices containing them for separating individual phases from gas-liquid and liquid-liquid two-phase mixtures for a range of flow regimes. The present invention also relates to methods of making said fluid-phase separators and devices containing them.

Abstract: The present invention is generally directed to a microfabricated gas chromatograph column having two patterned substrates, each optionally having a stationary phase material coating, bonded together to provide a continuous flow channel. The flow channel can have a serpentine arrangement or a modified serpentine arrangement comprising alternating series of consecutive turns in one direction where each series has enough turns to move carrier gas and analyte molecules from the center of the column cross section to an outer wall of the channel or from one outer wall of the channel to the opposite outer wall. Different portions of the substrates can be coated with differing thicknesses of stationary phase material and/or with different stationary phase materials. The column can have a circular cross-section or a semi-circular cross-section where the flat portion of the cross-section has grooves. Also disclosed is the related method of making the microfabricated gas chromatograph column.

Abstract: A method of forming a column (100 and 200) for use with an analytical chemical instrument. The method includes placing a frit (102 and 202) in proximity to a distal end (110 and 210) of a tube (104 and 204) having an internal bore (106 and 206) adapted to receive packing material (108 and 208) for selectively interacting with an analyte of interest in a sample. The method further includes laser welding the frit to the tube and inserting packing material within the internal bore of the tube. A column formed in accordance with this method.

Abstract: An oxygen separator for separating oxygen from ambient air utilizing a vacuum swing adsorption process has a mass of less than 2.3 kg. A carrier is mountable on a person to support the oxygen separator for ambulatory use.

Abstract: The subject invention concerns zirconia-based hybrid organic-inorganic sol-gel coating for optional use as a stationary phase in capillary microextraction (CME), gas chromatographic (GC), high performance liquid chromatography (HPLC), capillary electrophoresis (CE), capillary electrochromatography (CEC) and related analytical techniques. Sol-gel chemistry is employed to chemically bind a hydroxy-terminated silicone polymer (polydimethyldiphenylsiloxane, PDMDPS) to a sol-gel zirconia network. In one embodiment, a fused silica capillary is filled with a properly designed sol solution to allow for the sol-gel reactions to take place within the capillary. In the course of this process, a layer of the evolving hybrid organic-inorganic sol-gel polymer becomes chemically bonded to the silanol groups on the inner capillary walls.

Abstract: Improved microcolumns and methods for producing microcolumns particularly suitable for use in gas chromatographs are disclosed. In particular, following deposition of the stationary phase coating, the microcolumns are subjected to a postcoating treatment with a molecule that binds to the active sites in the stationary phase column thereby eliminating or reducing loss of gas chromatograph performance associated with those active sites. The postcoating treatment molecule binds to the same active sites as the analytes of interest.

Abstract: An HPLC column holding apparatus used to mount an HPLC column in one of a plurality of positions is disclosed herein. The apparatus comprises a clip-device interface that secures the apparatus to a platform and a clip-column interface that secures the HPLC column to the apparatus.

Abstract: Improved micro-columns and methods for producing micro-columns particularly suitable for use in gas chromatographs are disclosed. In particular, following deposition of the stationary phase coating, the micro-columns are subjected to a postcoating treatment with a molecule that binds to the active sites in the stationary phase micro-column thereby eliminating or reducing loss of gas chromatograph performance associated with those active sites. The postcoating treatment molecule binds to the same active sites as the analytes of interest.

Abstract: An analytical column includes a coating that absorbs at least one of ultraviolet (UV) and visible (VIS) radiant energy and converts the radiant energy into heat.

Abstract: Disclosed are systems and methods that include a thermal desorption unit, a chromatographic column, and an interface device between the unit and the column. The interface device controls the fluid flowing into the column, such as by providing additional carrier gas to maintain a substantially constant gas flow or velocity, by proving a controlled temperature increase, or by venting a portion of the gas received from the thermal desorption unit, thereby removing the dependence on the thermal desorption unit for such control. In some embodiments, the interface is a chromatographic injector. In certain embodiments, a transfer line from the desorption unit is coupled to the same port of the interface device as the chromatographic column. In some of these embodiments, this is accomplished by employing a special adaptor.