The invention relates to methods for predicting the response of a subject suffering from asthma or a respiratory disorder to a therapy comprising a Th2 pathway modulator and a device for use in such methods.
The present disclosure relates to sensor systems and methods for analysing fluid samples. The sensor system comprises a housing (220) having an inlet for a fluid sample to enter the housing, an outlet for the fluid sample to exit the housing, and a fluid sample path within the housing for the fluid sample to flow between the inlet and the outlet. The sensor system also comprises an ionizer (210) which is external to the housing and which is for ionizing the fluid sample at a first location on the fluid sample path to generate sample ions, an ion mobility filter (212) which is at least partially located within the housing and which is for filtering the generated sample ions at a second location on the fluid sample path, and a detector (214) which is external to the housing and which is for detecting the sample ions which pass through the ion mobility filter at a third location on the fluid sample path.
The present techniques relate to methods of manufacturing MEMS gas sensors, for example, an ion mobility filter which may be used as a field asymmetric ion mobility spectrometry filter. The method comprises a step of providing a support with an aperture (S300, S302) and forming electrical connections (S304) in the support. The method also comprises steps of attaching an electrode layer to the support (S306) so that the electrode layer covers the aperture and forming a plurality of ion mobility electrodes (S308) by mechanically dicing through the electrode layer. Each adjacent pair of electrodes defines an ion channel between them and each electrode is separate from the adjacent electrode(s).
The waveform generator (10) comprises a switch (13). The waveform generator (10) comprises a transformer (15) having a primary side circuit and a secondary side circuit. The primary side circuit has a first terminal arranged to be conductively coupled to a DC voltage source, and a second terminal conductively coupled to the switch (13). The waveform generator (10) further comprises a controller (11) arranged to supply a drive signal to the switch for switching the switch between on and off states. The controller (11) is arranged to adjust the frequency of the drive signal so as to control at least one of the peak voltage and the duty cycle of a waveform generated by the waveform generator (10). The frequency of the drive signal may be adjusted as the voltage level of the DC voltage source remains constant. The frequency of the drive signal may be adjusted in response to a change in the voltage level of the DC voltage source.
H03K 3/017 - Adjustment of width or dutycycle of pulses
H03B 19/14 - Generation of oscillations by non-regenerative frequency multiplication or division of a signal from a separate source by means of discharge device or semiconductor device with more than two electrodes by means of a semiconductor device
G01N 27/624 - Differential mobility spectrometry [DMS]; Field asymmetric-waveform ion mobility spectrometry [FAIMS]
A method for the early detection and monitoring of the progression of cancer by detecting breath biomarkers is provided. The method comprises assessing the activity of an aldo-keto reductase by measuring the concentration of an exogenous substrate for said enzyme and/or measuring the concentration of a metabolite of said substrate in exhaled breath of a subject. Preferably, the cancer is lung cancer.
Disclosed is a method for collecting different selected exhaled breath samples, or fractions thereof, on a single sample capture device, the method comprising the steps of: (a) collecting a first exhaled breath sample by contacting the sample with a capture device comprising an adsorbent material; (b) collecting a second exhaled breath sample by contacting the second sample with said capture device, wherein the first and second exhaled breath samples are caused to be captured on the capture device in a spatially separated manner.
B01D 53/02 - Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases or aerosols by adsorption, e.g. preparative gas chromatography
A61B 5/097 - Devices for facilitating collection of breath or for directing breath into or through measuring devices
A61B 5/08 - Measuring devices for evaluating the respiratory organs
B01J 20/20 - Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising carbon obtained by carbonising processes
B01J 20/28 - Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties
8.
Fluid sensor system and method for analysing fluid
A sensor system comprising a housing having an inlet aperture through which fluid enters the housing and a conditioning material in the housing, the conditioning material being adapted to control levels of a substance within the housing. The sensor system comprises a sensor for analysing the fluid in the housing. The sensor system comprises circulation means which is configured to alternate circulation of fluid within the housing between a sensing fluid path in which the fluid is analysed by the sensor and a second fluid path in which the fluid flow is conditioned. A method for analysing fluid in a housing using a sensor is also provided.
B01D 53/04 - Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases or aerosols by adsorption, e.g. preparative gas chromatography with stationary adsorbents
We describe a method and apparatus for detecting humidity using a Field Asymmetric Ion Mobility Spectrometry (FAIMS) system. The system may comprise an ionizer for generating ions within a gas sample, wherein each ion has an associated ion mobility; an ion filter for separating the ions by applying a compensation field and a dispersion field to the generated ions; a detector for detecting an output from the ion filter; and a processor. The processor may be configured to extract a spectrum of peak intensity of the detected output as a function of the compensation field and the dispersion field; calculate a turning point for the extracted spectrum; determine operating parameters of the field asymmetric ion mobility system; obtain, from a database, a plurality of known turning points each of which have an associated humidity and each of which were obtained using a field asymmetric ion mobility system having operating parameters aligned with the determined operating parameters; and determine the humidity by comparing the calculated turning point with known turning points.
G01N 27/62 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electric discharges, e.g. emission of cathode
G01N 27/624 - Differential mobility spectrometry [DMS]; Field asymmetric-waveform ion mobility spectrometry [FAIMS]
Mobile device (110) is disclosed. The present techniques relate to a mobile device or portable electronic device, particularly a device including a breath sampling device. The mobile electronic device (110) comprises a collection device (112) for collecting and storing a gas sample. The collection device (112) is accessible to enable analysis of the gas stored in the collection device (112). The collection device (112) comprises a mouthpiece (118) into which a user exhales. The collection device (112) further comprises a plurality of sorbent tubes (114) to collect and store the breath sample(s). Each tube (114) has a one-way valve (116) to prevent captured breath escaping.
A method of manufacture for a ion mobility filter is disclosed. The method of manufacturing an ion filter for a spectrometry system includes providing a sheet of conductive material and defining a plurality of ion filters on the sheet. The definition of the plurality of ion filters is achieved by forming an electrode layer for each ion filter on the sheet, where each electrode layer comprises at least one ion channel and an isolation channel surrounding the at least one ion channel. A support layer on each electrode layer is also formed. Each support layer comprises an aperture at least partially aligned with the at least one ion channel. The ion filter is then separated. The risk of contaminants entering the at least one ion channel when separating the ion filters is reduced by surrounding the at least one ion channel with the isolation channel.
G01N 27/62 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electric discharges, e.g. emission of cathode
H01J 49/00 - Particle spectrometers or separator tubes
H01J 49/06 - Electron- or ion-optical arrangements
G01N 27/624 - Differential mobility spectrometry [DMS]; Field asymmetric-waveform ion mobility spectrometry [FAIMS]
An ion filter for filtering ions in a gas sample. The ion filter has a first ion channel for filtering ions from a target chemical in the gas sample. The ion filter has a second ion channel for filtering ions from the target chemical in the gas sample. The second ion channel is separated from the first ion channel. A temperature control region is in thermal contact with the first and second ion channels for controlling a difference in temperature between the first and second ion channels. A method of filtering ions from a target chemical in a gas sample is also provided.
An ion mobility filter is disclosed. The present invention relates to but not exclusively a field asymmetric ion spectrometry filter. For example, we describe an ion filter for filtering ions in a gas sample. The ion filter is comprised of a plurality of electrodes, a first ion channel, and a second ion channel. The first ion channel filters ions from a target chemical in the gas sample, defines a gap between a first pair of electrodes in the plurality of electrodes, and has a first ion channel gap width. The second ion channel filters ions from the target chemical in the gas sample, defines a gap between a second pair of electrodes in the plurality of electrodes, and has a second ion channel gap width. The first ion channel gap width is greater than the second ion channel gap width.
G01N 27/62 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electric discharges, e.g. emission of cathode
G01N 27/624 - Differential mobility spectrometry [DMS]; Field asymmetric-waveform ion mobility spectrometry [FAIMS]
A waveform generator configured to generate two waveforms of opposite polarity so as to provide a voltage gain across a load. The waveform generator has a primary side circuit comprising a first inductor. The waveform generator has a secondary side circuit comprising a second inductor, a first output region conductively coupled to the load, and a second output region conductively coupled to the load. The second inductor is inductively coupled to the first inductor. The first inductor is conductively coupled to the first output region so as to supply a first of the two waveforms to the load. The second inductor is conductively coupled to the second output region so as to supply a second of the two waveforms to the load. A system incorporating the waveform generator and a method of driving the waveform generator are also provided.
H03K 3/57 - Generators characterised by the type of circuit or by the means used for producing pulses by the use of an energy-accumulating element discharged through the load by a switching device controlled by an external signal and not incorporating positive feedback the switching device being a semiconductor device
G01N 27/624 - Differential mobility spectrometry [DMS]; Field asymmetric-waveform ion mobility spectrometry [FAIMS]
G05F 3/08 - Regulating voltage or current wherein the variable is dc
H03K 17/687 - Electronic switching or gating, i.e. not by contact-making and -breaking characterised by the use of specified components by the use, as active elements, of semiconductor devices the devices being field-effect transistors
Disclosed is apparatus for collecting a breath sample from a human subject, the apparatus comprising at least a mask portion which, in use, is positioned over the subject's mouth and nostrils so as to collect breath exhaled from the subject, the apparatus further comprising movement detection means for detecting movement of the mask portion, and an alarm signal generator, which alarm signal generator generates an alarm signal if the subject's head is outside a predetermined range of acceptable orientations during collection of a breath sample, but only after the subject's head has been outside the predetermined range of acceptable orientations for a defined or measurable period of time.
Disclosed is a method of identifying if a subject is sufficiently prepared to permit successful colonoscopic examination, the method comprising the steps of: (a) obtaining a stool sample from a subject having undergone preparation for a colonoscopic examination; (b) analysing the sample to detect the presence and/or amount of faecal matter, if any, in the stool sample; and (c) from the analysis in step (b), identifying whether the subject has been sufficiently prepared.
G01N 27/62 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electric discharges, e.g. emission of cathode
A61B 1/31 - Instruments for performing medical examinations of the interior of cavities or tubes of the body by visual or photographical inspection, e.g. endoscopes; Illuminating arrangements therefor for the rectum, e.g. proctoscopes, sigmoidoscopes
G01N 33/483 - Physical analysis of biological material
G01N 33/487 - Physical analysis of biological material of liquid biological material
G01N 33/50 - Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing
A61B 5/00 - Measuring for diagnostic purposes ; Identification of persons
A61B 5/097 - Devices for facilitating collection of breath or for directing breath into or through measuring devices
A61B 5/08 - Measuring devices for evaluating the respiratory organs
B01D 46/00 - Filters or filtering processes specially modified for separating dispersed particles from gases or vapours
B01D 53/02 - Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases or aerosols by adsorption, e.g. preparative gas chromatography
B01D 53/30 - Controlling by gas-analysis apparatus
G01N 33/497 - Physical analysis of biological material of gaseous biological material, e.g. breath
18.
Method for collecting a selective portion of a subject's breath
A61B 5/083 - Measuring rate of metabolism by using breath test, e.g. measuring rate of oxygen consumption
A61B 5/091 - Measuring volume of inspired or expired gases, e.g. to determine lung capacity
A61B 5/00 - Measuring for diagnostic purposes ; Identification of persons
A61B 10/00 - Other methods or instruments for diagnosis, e.g. for vaccination diagnosis; Sex determination; Ovulation-period determination; Throat striking implements
A61B 5/085 - Measuring impedance of respiratory organs or lung elasticity
A61M 16/00 - Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
A corona discharge ionizer device which emits ions generated by corona discharge to a gas flow to be ionized includes a discharge electrode having a pin configured tip portion. A second grid electrode positioned at a spaced distance from the discharge electrode is provided. The grid electrode is preferably formed from a sheet configured material which has at least one hole formed therein adapted and configured to permit the gas flow to pass therethrough. A power supply is coupled to the discharge electrode and grid electrode configured cause ion emission from the discharge electrode. The power supply is preferably an alternating current power supply configured to produce an alternating electric field region in close proximity to the tip portion of the discharge electrode sufficient to cause avalanche breakdown in the gas flowing in close proximity to the tip portion of the discharge electrode.
H01J 49/16 - Ion sources; Ion guns using surface ionisation, e.g. field-, thermionic- or photo-emission
G01N 27/62 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electric discharges, e.g. emission of cathode
20.
Interdigitated electrode configuration for ion filter
An ion filter and a method of manufacturing an ion filter. The method including providing a monolithic structure; selectively removing regions of the structure, to form a pair of electrodes defining at least one ion channel therebetween. The electrodes are preferably mechanically connected at one or more locations by a portion of the structure; wherein the connecting portion of the structure provides a higher electrical impedance than the filter would provide without such a mechanical connection, to thereby electrically separate the electrodes.
H01J 49/00 - Particle spectrometers or separator tubes
G01N 27/62 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electric discharges, e.g. emission of cathode
H01J 49/42 - Stability-of-path spectrometers, e.g. monopole, quadrupole, multipole, farvitrons
21.
Sensor apparatus and method for use with gas ionization systems
An ion mobility gas detector apparatus including a detector core, an inlet gas path, an exhaust gas path, a source of diluent gas, and at least one or more sensors for measuring temperature, pressure and humidity of gas streams. Further included is a mixing mechanism adapted to mix at least first and second gas streams in response to one or more sensor measurements. A controller is provided for applying drive signals to the detector core.
G01N 27/62 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electric discharges, e.g. emission of cathode
H01J 49/04 - Arrangements for introducing or extracting samples to be analysed, e.g. vacuum locks; Arrangements for external adjustment of electron- or ion-optical components
G01N 27/68 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electric discharges, e.g. emission of cathode using electric discharge to ionise a gas
Ion filter for FAIMS fabricated using the LIGA technique. The ion filter is manufactured using a metal layer to form the ion channels and an insulating support layer to hold the structure rigidly together after separation of the metal layer into two electrodes.
G01N 27/62 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electric discharges, e.g. emission of cathode
H01J 49/06 - Electron- or ion-optical arrangements
H01J 49/00 - Particle spectrometers or separator tubes
An apparatus, system and method for detecting, identifying, classifying and/or quantifying chemical species in a gas flow using a micro-fabricated ion filter coupled to a system adapted to apply drive signals to the ion filter. Coupled to the ion filter is a system adapted to measure the output of the ion filter, which in turn is coupled to a system adapted to extract numerical parameters from the measured output of the ion filter to facilitate chemical detection, identification, classification and/or quantification of the gas flow.
G01N 27/62 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electric discharges, e.g. emission of cathode
24.
Interdigitated electrode configuration for ion filter
An ion filter and a method of manufacturing an ion filter. The method including providing a monolithic structure; selectively removing regions of the structure, to form a pair of electrodes defining at least one ion channel therebetween. The electrodes are preferably mechanically connected at one or more locations by a portion of the structure; wherein the connecting portion of the structure provides a higher electrical impedance than the filter would provide without such a mechanical connection, to thereby electrically separate the electrodes.
H01J 49/00 - Particle spectrometers or separator tubes
G01N 27/62 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electric discharges, e.g. emission of cathode
H01J 49/42 - Stability-of-path spectrometers, e.g. monopole, quadrupole, multipole, farvitrons
Ion filter for FAIMS fabricated using the LIGA technique. The ion filter is manufactured using a metal layer to form the ion channels and an insulating support layer to hold the structure rigidly together after separation of the metal layer into two electrodes.
H01J 49/00 - Particle spectrometers or separator tubes
H01J 49/06 - Electron- or ion-optical arrangements
G01N 27/62 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electric discharges, e.g. emission of cathode
26.
Sensor apparatus and method for use with gas ionization systems
An ion mobility gas detector apparatus including a detector core, an inlet gas path, an exhaust gas path, a source of diluent gas, and at least one or more sensors for measuring temperature, pressure and humidity of gas streams. Further included is a mixing mechanism adapted to mix at least first and second gas streams in response to one or more sensor measurements. A controller is provided for applying drive signals to the detector core.
G01N 27/68 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electric discharges, e.g. emission of cathode using electric discharge to ionise a gas
G01N 27/62 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electric discharges, e.g. emission of cathode
H01J 49/04 - Arrangements for introducing or extracting samples to be analysed, e.g. vacuum locks; Arrangements for external adjustment of electron- or ion-optical components
A corona discharge ionizer device which emits ions generated by corona discharge to a gas flow to be ionized includes a discharge electrode having a pin configured tip portion. A second grid electrode positioned at a spaced distance from the discharge electrode is provided. The grid electrode is preferably formed from a sheet configured material which has at least one hole formed therein adapted and configured to permit the gas flow to pass therethrough. A power supply is coupled to the discharge electrode and grid electrode configured cause ion emission from the discharge electrode. The power supply is preferably an alternating current power supply configured to produce an alternating electric field region in close proximity to the tip portion of the discharge electrode sufficient to cause avalanche breakdown in the gas flowing in close proximity to the tip portion of the discharge electrode.
An apparatus, system and method for detecting, identifying, classifying and/or quantifying chemical species in a gas flow using a micro-fabricated ion filter coupled to a system adapted to apply drive signals to the ion filter. Coupled to the ion filter is a system adapted to measure the output of the ion filter, which in turn is coupled to a system adapted to extract numerical parameters from the measured output of the ion filter to facilitate chemical detection, identification, classification and/or quantification of the gas flow.
B01D 59/46 - Separation by mass spectrography using only electrostatic fields
H01J 49/00 - Particle spectrometers or separator tubes
G01N 27/62 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electric discharges, e.g. emission of cathode
An ion mobility spectrometer is described which makes use of a pulsed flow pump to draw gas through an ion filter in pulsed operation. A gas counterflow may also be provided, in some embodiments this may also be a pulsed counterflow.
A method and sensor for monitoring chemical species in a gas flow are described. An ionized sample of gas is passed through a flow channel, with a DC electric field applied transverse to the longitudinal axis of the channel. Any electric current produced by the ion flow is measured, with variations in the current being indicative of a change in composition of the gas flow. In certain embodiments, the DC field may be varied over time, to sweep the field voltage. The detected current against field voltage graph may be taken as a profile of a particular gas composition. Variations in the profile again are indicative of a change in gas composition.
An ion mobility spectrometer is described having an ion filter in the form of at least one ion channel having a plurality of electrodes. A time-varying electric potential applied to the conductive layers allows the filler to selectively admit ion species. The electric potential has a drive and a transverse component, and in preferred embodiments each of the electrodes is involved in generating a component of both the drive and transverse fields. The device may be used without a drift gas flow. Microfabrication techniques are described for producing microscale spectrometers, as are various uses of the spectrometer.
A smart FAIMS sensor system and method includes a 2/2-electrode filter that pumps the ions through the system and separates the ionic species, a detector for collecting the separated ions and generating a detector signal in response to the collected ions, and a controller configured to change the operating parameters of the system in response to changes in the sensor's environment detected by the sensor. The ability to dynamically change the operating parameters of the sensor enables the sensor to maintain high sensitivity to environmental threats while decreasing the incidences of false positive events.
An ion filter (10) for use in ion mobility spectrometry is described, together with a method for manufacturing the filter. The filter (10) is manufactured by removing portions from a monolithic structure to form a pair of electrodes which remain mechanically connected. The connecting portion (22) provides sufficient electrical impedance between the electrodes to effectively electrically separate the electrodes. The connecting portion may be doped or chemically modified to obtain a desired impedance, or this may be obtained through appropriate selection of physical dimensions.
H01J 49/00 - Particle spectrometers or separator tubes
H01J 49/06 - Electron- or ion-optical arrangements
G01N 27/62 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electric discharges, e.g. emission of cathode
H01J 49/42 - Stability-of-path spectrometers, e.g. monopole, quadrupole, multipole, farvitrons
An ion mobility spectrometer is described having an ion filter in the form of at least one ion channel having a plurality of electrodes. A time-varying electric potential applied to the conductive layers allows the filler to selectively admit ion species. The electric potential has a drive and a transverse component, and in preferred embodiments each of the electrodes is involved in generating a component of both the drive and transverse fields. The device may be used without a drift gas flow, Microfabrication techniques are described for producing microscale spectrometers, as are various uses of the spectrometer.
An ion mobility spectrometer is described having an ion filter in the form of multiple parallel ion channels defined by conductive layers separated by non-conductive layers. A time-varying electric potential applied to the conductive layers allows the filter to selectively admit ion species. The device may be used without a drift gas flow. Microfabrication techniques are described for producing microscale spectrometers, as are various uses of the spectrometer.
A smart FAIMS sensor system and method includes a 2/2-electrode filter that pumps the ions through the system and separates the ionic species, a detector for collecting the separated ions and generating a detector signal in response to the collected ions, and a controller configured to change the operating parameters of the system in response to changes in the sensor's environment detected by the sensor. The ability to dynamically change the operating parameters of the sensor enables the sensor to maintain high sensitivity to environmental threats while decreasing the incidences of false positive events.
The present invention relates to an ion drive for selectively isolating an analyte of interest and methods of use thereof. The ion drive includes a substrate with channels therethrough, a conductive material coating on the bottom and top of the substrate, a top electrical lead connected to the conductive material coating covering the top of the substrate, and a bottom electrical lead connected to the conductive material coating covering the bottom of the substrate. The invention further relates to an odor emitter which is made up of an ion drive mounted towards the top of a vessel.
The present invention relates to a three dimensional preconcentrator and inlet heater. The preconcentrator consists of a substrate with passageways, a conductive material coated to the top and the bottom of the substrate and an adsorbent coating covering the entire substrate. This substrate is suspended in a holding frame by a connecting bridge. The preconcentrator may also include a resistor and a proportional-integral-differential controller. The device may be used inline with a detector and can be retrofitted to existing devices. An array of preconcentrators may also be formed. The invention also relates to methods of use of the preconcentrator and methods of manufacture. A method of use includes contacting an analyte and a preconcentrator, allowing the analyte to adsorb to the preconcentrator and then desorbing the analyte. A method of manufacture involves applying the adsorbent coating by misted chemical deposition.
B01D 53/02 - Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases or aerosols by adsorption, e.g. preparative gas chromatography
A compact ionization source includes first and second electrodes, each having a plurality of fingers that are interdigitated with each other. The spacing between the first and second electrode, preferably less than 1 mm, creates a large electric field when a potential is applied across the first and second electrodes. The large electric field creates an ionization volume between the fingers of the first and second electrode and ionizes a portion of the molecules occupying the ionization volume. The interdigitated fingers of the first and second electrodes allow for a narrow gap separating the electrodes while presenting a large flow area for ionizing molecules for downstream analysis.
An ion gate is disposed between a first volume occupied by a first carrier gas and ions of the first carrier gas and a second volume occupied by a second carrier gas. The ion gate includes at least one channel connecting the first volume to the second volume, a first electrode disposed on an inlet surface of the ion gate facing the first volume, and a second electrode disposed on an outlet surface of the ion gate facing the second volume. Ions are transported from the first volume to the second volume through the channel under an electric field produced by the first and second electrode.