Abstract: An ion mobility spectrometer (100) comprising a first ion source (102-1, 108-1) for providing positive ions to be analyzed, an electric field applier arranged to provide an electric field configured to move the positive ions in a first direction towards a first ion detector (106-1, 110-1) adapted for detecting the positive ions, and a second ion source (102-2, 108-2) for providing negative ions to be analyzed, wherein the electric field applier is arranged to move the negative ions in a direction opposite to the first direction, towards the first ion source (102-1, 108-1) and towards a second ion detector (106-1, 110-1) adapted for detecting the negative ions.

Abstract: A thermal desorption apparatus is configured to detect a substance of interest in a sample, the apparatus comprising: a wand configured to support a swab and a detector comprising an analyser arranged to detect a substance of interest, wherein the wand is configured to couple to the detector such that thermal desorption of a sample from the swab provides a part of the sample to the analyser.

Abstract: An ionizing apparatus for ionizing a sample of gaseous fluid. The ionizing apparatus comprises an ionizer configured to provide reactant ions; an ion modifier configured to modify the reactant ions, and a reaction region arranged to receive the modified reactant ions and a sample and to combine the sample with the modified reactant ions to ionize the sample for analysis by a detector configured to identify a substance of interest in the sample.

Abstract: The present application is directed to a process for calibrating a detection apparatus, especially an ion mobility spectrometer, using isoflurane (CAS Reg. No. 26675-46-7) as a chemical standard whereby calibrating the detection apparatus for a known target chemical is based on an evaluation of the experimental data collected for the negative isoflurane monomer ion against the experimental data collected for the negative isoflurane dimer ion.

Abstract: An on-demand vapor generator includes a vapor chamber configured to produce a vapor and a vapor absorption assembly configured to receive flows of vapor from the vapor chamber. The vapor absorption assembly includes a first vapor-permeable passage having a passage outlet and at least one second vapor-permeable passage that is closed. When vapor absorption assembly receives a flow of vapor from the vapor chamber, the flow of vapor passes through the first vapor-permeable passage to the passage outlet at least substantially without absorption of vapor from the flow of vapor. However, when a flow of vapor is not received from the vapor chamber, vapor entering the vapor absorption assembly from the vapor chamber passes into the first vapor-permeable passage and the at least one second vapor-permeable passage and is at least substantially absorbed.

Abstract: An ion mobility spectrometry method comprising determining whether a sample comprises ions having a first characteristic, and in the event that it is determined that the sample comprises ions having the first characteristic, applying thermal energy together with a radio frequency, RF, electric field to parent ions so as to obtain daughter ions having a second characteristic for inferring at least one identity for the parent ions based on the first characteristic and the second characteristic.

Abstract: Synchronized ion modification systems and techniques are described. An ion modifier can be used to modify a portion of ions that enter a drift chamber via a gate that controls entry of the ions to the drift chamber. A controller that is communicatively coupled to the ion modifier is configured to control the ion modifier to select a portion of the ion to be modified. In embodiments, the controller selects the portion based on a detector's previous response to other ions that are formed from a sample from which the ions were formed. The other ions, for example, correspond to ions that are associated with a peak in previous operation of a spectrometer.

Abstract: IMS apparatus has an inlet with a preconcentrator opening into a reaction region where analyte molecules are ionized and passed via a shutter to a drift region for collection and analysis. A pump and filter arrangement supplies a flushing flow of clean gas to the housing in opposition to ion flow. A pressure pulser connects with the housing and is momentarily switched to cause a short drop in pressure, in the housing to draw in a bolus of analyte sample from the preconcentrator. Just prior to admitting a bolus of sample, the pump is turned off so that the flushing flow drops substantially to zero, thereby prolonging the time the analyte molecules spend in the reaction region.

Abstract: RF generators including active devices driving series resonant circuits are described. The series resonant circuits include a self-resonant dual inductor. The RF generators can be used to drive capacitive loads.

Abstract: An accessory for a device includes an actuator that is configured to be activated to operate a switch on the device when the accessory is physically engaged with the device. The switch is operable to cause the device to switch between on and off modes in which the device is configured to function. The off mode is a mode in which the device consumes less energy than when in the on mode. A controller is communicatively coupled with the actuator and is configured to activate the actuator to operate the switch when power is applied to the actuator.

Abstract: Spectrometers including integrated capacitive detectors are described. An integrated capacitive detector integrates ion current from the collector (220) into a changing voltage. The detector includes a collector configured to receive ions in the spectrometer, a dielectric (228), and a plate (232) arranged in an overlapping configuration with collector on an opposite side of the dielectric. The detector also includes an amplifier (226).

Abstract: A detection device including an ionization region, an ion gate comprising two electrodes, an ion modifier comprising two electrodes, a drift chamber and a collector. The ion gate and ion modifier are combined so the ion gate is one of the ion modifier electrodes.

Abstract: Spectrometers including integrated capacitive detectors are described. An integrated capacitive detector integrates ion current from the collector (768) into a changing voltage. The detector includes a collector configured to receive ions in the spectrometer, a dielectric, and a plate arranged in an overlapping configuration with collector on an opposite side of the dielectric. The detector also includes an amplifier (764). A capacitive detector with offset (776) is described.

Abstract: An ion mobility spectrometer has a pair of electrodes and midway along the drill chamber. A high field is applied between the electrodes and sufficient to modify ions in the region of the electrodes such that they move at a different rate towards the collector plate. This is used to modify the time of flight of selected ions or ion clusters and enable identification of ambiguous peaks on the IMS spectrum.

Abstract: A substance detection device, including a chemical substance analyzer, including an ion mobility spectrometer (IMS), a desorber, a conduit, and a membrane. The membrane extends across a cross-section of the conduit, and the membrane is positioned to have a desorber side in gas communication with the desorber and an analysis side opposite the desorber side. The substance detection device can be configured to direct a portion of a chemical substance to the desorber through the conduit so that at least a portion of the entrained chemical substance is transferred to the membrane by interacting with the desorber side of the membrane. The membrane is adapted to diffuse at least a portion of the chemical substance transferred to the membrane through the membrane to the analysis side. The device also includes a particle separator including a protuberance extending into a collection chamber of the particle separator.

Abstract: A detecting method using an IMS apparatus with a preconcentrator outside its inlet aperture. Analyte vapor is adsorbed during a first phase when substantially no gas is admitted to the reaction region. The preconcentrator is then energized to desorb the analyte molecules and create a volume of desorbed molecules outside the IMS housing. Next, a pressure pulser is energized momentarily to drop pressure in the housing and draw in a small sip of the analyte molecules from the desorbed volume through the aperture. This is repeated until the concentration of analyte molecules in the desorbed volume is too low for accurate analysis, following which the apparatus enters another adsorption phase.

Abstract: A vapor generator system (1, 101) for an IMS (4, 104) or other apparatus has a chamber (9, 109) in which vapor is produced. A fan or other flow generator (6, 106) is connected to an inlet (8, 108) of the vapor chamber (9, 109) and its outlet (13, 113) is connected to an adsorbent passage (14, 114), such as formed by a bore through a block (15) of carbon. When the fan (6, 106) is on gas flows through the vapor chamber (9, 109) and the adsorbent passage (14, 114) to the IMS (4, 104) or other outlet, with little vapor being adsorbed in the passage. When the fan (6, 106) is off, any vapor molecules that escape to the adsorbent passage (14, 114) do so at a low rate such that substantially all is adsorbed and no vapor escapes.

Abstract: An ion mobility spectrometer has a reaction region separated from a drift region by an electrostatic gate. A doping circuit supplies a dopant to the reaction region but the drift region is undoped. Two high field ion modifiers are located one after the other in the drift region. One ion modifier can be turned on to remove dopant adducts from the admitted ions, or both ion modifiers can be turned on so that the ions are also fragmented. In this way, several different responses can be produced to provide additional information about the nature of the analyte substance and distinguish it from interferents.

Abstract: A field asymmetric ion mobility spectrometer (FAIMS) has an analyte ion source assembly by which an analyte substance is ionized and supplied to the inlet of the spectrometer. The ion source assembly has an upstream source of clean, dry air and two ion sources of opposite polarity arranged at the same distance along the flow path. The ion sources are arranged so that the overall charge of the plasma produced is substantially neutral. The analyte substance is admitted via an inlet downstream of the ion sources and flows into a reaction region of enlarged cross section to slow the flow and increase the time for which the analyte molecules are exposed to the plasma.

Abstract: IMS apparatus has a preconcentrator outside its inlet aperture. Analyte vapor is adsorbed during a first phase when substantially no gas is admitted to the reaction region. The preconcentrator is then energized to desorb the analyte molecules and create a volume of desorbed molecules outside the IMS housing. Next, a pressure pulser is energized momentarily to drop pressure in the housing and draw in a small sip of the analyte molecules from the desorbed volume through the aperture. This is repeated until the concentration of analyte molecules in the desorbed volume is too low for accurate analysis, following which the apparatus enters another adsorption phase.