A diaphragm valve for gas analysis applications is provided. The valve includes a valve cap provided with a plurality of process conduits extending therethrough, a valve body engageable with the valve cap and having a body interface provided with a recess, a diaphragm positioned between the valve cap and valve body and having a process groove for circulating fluid therein, the process groove engaging the recess, a plunger assembly provided within the valve body, the plunger assembly comprising a plurality of plungers movable between a closed position wherein the plunger engages the diaphragm, and an open position wherein the plunger is spaced from the diaphragm, and an actuating assembly comprising a gas inlet to allow the injection of actuating gas therein, the actuating assembly comprising a purging system for purging a region located between the diaphragm and the body interface, whereby the actuating gas is used for purging the region.

The present invention relates to a valve unit (100) for a chromatography apparatus, the valve unit comprising a fluid inlet (110) configured to receive an input fluid, a fluid outlet (120) configured to provide an output fluid, a first pair of fluid ports (131,132) configured to be coupled to a first column, a second pair (141,142) of fluid ports configured to be coupled to a second column, a coupling valve assembly (200) configured to direct fluid between a selection of the fluid inlet (110), the fluid outlet (120), the first pair of fluid ports (131,132) and the second pair of fluid ports (141,142) in response to one or more control signals, wherein the coupling valve assembly is configured to direct fluid using a selection of membrane valves coupled by fluid channels comprised in a body of the coupling valve assembly. The invention further relates to a chromatography apparatus comprising the valve unit and a membrane valve comprised in the valve unit.

The present invention relates to a valve unit (100) for a chromatography apparatus, the valve unit comprising a fluid inlet (110) configured to receive an input fluid, a fluid outlet (120) configured to provide an output fluid, a first pair of fluid ports (131,132) configured to be coupled to a first column, a second pair (141,142) of fluid ports configured to be coupled to a second column, a coupling valve assembly (200) configured to direct fluid between a selection of the fluid inlet (110), the fluid outlet (120), the first pair of fluid ports (131,132) and the second pair of fluid ports (141,142) in response to one or more control signals, wherein the coupling valve assembly is configured to direct fluid using a selection of membrane valves coupled by fluid channels comprised in a body of the coupling valve assembly. The invention further relates to a chromatography apparatus comprising the valve unit and a membrane valve comprised in the valve unit.

Example aspects of a volatile organic compound detection device, a wearable health monitoring device, and a method of monitoring a user's health are disclosed. The volatile organic compound detection device can comprise a collector comprising a collector material configured to collect volatile organic compounds given off from a user's skin; a separator comprising a gas chromatography column configured to separate mixtures of the volatile organic compounds into their constituent chemicals; and an identifier comprising a detector and a processor, the detector configured to transduce the constituent chemicals into a signal, the processor configured to process the signal to identify specific volatile organic compounds indicative of a health condition.

Example aspects of a volatile organic compound detection device, a wearable health monitoring device, and a method of monitoring a user's health are disclosed. The volatile organic compound detection device can comprise a collector comprising a collector material configured to collect volatile organic compounds given off from a user's skin; a separator comprising a gas chromatography column configured to separate mixtures of the volatile organic compounds into their constituent chemicals; and an identifier comprising a detector and a processor, the detector configured to transduce the constituent chemicals into a signal, the processor configured to process the signal to identify specific volatile organic compounds indicative of a health condition.

The disclosed system and method improve measurement of trace volatile chemicals, such as by Gas Chromatography (GC) and Gas Chromatography/Mass Spectrometry (GCMS). A first trapping system can include a plurality of capillary columns in series and a focusing column fluidly coupled to a first detector. The first trapping system can retain and separate compounds in a sample, including C3 hydrocarbons and compounds heavier than C3 hydrocarbons (e.g., up to C12 hydrocarbons, or compounds having a boiling point around 250° C.), and can transfer the compounds from the focusing column to the first detector. A second trapping system can receive compounds that the first trapping system does not retain, and can include a packed trap and two columns. The second trapping system can remove water from the sample and can separate and detect compounds including C2 hydrocarbons and Formaldehyde.

The disclosed system and method improve measurement of trace volatile chemicals, such as by Gas Chromatography (GC) and Gas Chromatography/Mass Spectrometry (GCMS). A first trapping system can include a plurality of capillary columns in series and a focusing column fluidly coupled to a first detector. The first trapping system can retain and separate compounds in a sample, including C3 hydrocarbons and compounds heavier than C3 hydrocarbons (e.g., up to C12 hydrocarbons, or compounds having a boiling point around 250° C.), and can transfer the compounds from the focusing column to the first detector. A second trapping system can receive compounds that the first trapping system does not retain, and can include a packed trap and two columns. The second trapping system can remove water from the sample and can separate and detect compounds including C2 hydrocarbons and Formaldehyde.

An autosampler sets an injection valve to be in a sample filling state when a sample loop is filled with a sample, and, after completion of filling with the sample, switches the injection valve to an intermediate state and first connects only one end of the sample loop to a liquid delivery channel and an analysis channel. After the above, the injection valve is switched to the sample injection state and the sample loop is interposed between the liquid delivery channel and the analysis channel, so that the sample is injected into the analysis channel.

An autosampler sets an injection valve to be in a sample filling state when a sample loop is filled with a sample, and, after completion of filling with the sample, switches the injection valve to an intermediate state and first connects only one end of the sample loop to a liquid delivery channel and an analysis channel. After the above, the injection valve is switched to the sample injection state and the sample loop is interposed between the liquid delivery channel and the analysis channel, so that the sample is injected into the analysis channel.

Pressure-controlled splitting can be used to inject a chemical sample from an injection source to a detector (e.g., a mass spectrometer) for chemical analysis (e.g., gas chromatography or gas chromatography-mass spectrometry) with reduced peak widths. For example, the sample is first transferred to a first compression volume; then pressure in the system is increased to compress the sample to split it between a second compression volume and a column. The fraction of the sample split to the column can have reduced peak widths compared to the peak widths prior to compression and splitting yet can maintain the same peak height to preserve high sensitivity for trace level analysis. This portion of the sample can traverse the column and elute to the detector for analysis with reduced chemical noise. Faster injection rates can allow faster analysis times, as less separation of chemicals is needed before the sample reaches the detector.