Detector inlet and sampling method

Abstract

The inlet device for providing sample analyte vapor to a detector includes a sample receiving portion (110), a heating portion (120), a vapor pre-concentration portion (130), and a sampling inlet (140). The sample receiving portion is positioned to receive a gas flow carrying an aerosol sample analyte. The heating portion is positioned to heat the aerosol sample analyte to provide a sample analyte vapor. The device is positioned to provide the sample analyte vapor to both (i) the vapor pre-concentration portion and (ii) the detector via the sampling inlet.

Description

[Technical Field]

[0001] The present disclosure relates to the field of sample detection. [Background technology]

[0002] Various techniques exist for identifying the presence of a substance of interest in a given sample. Implementations of these techniques can be used to detect the presence of chemical warfare agents (CWAs) or toxic industrial chemicals (TICs), or other chemicals of interest, including explosives and their precursors. Spectroscopic techniques can be used to identify one or more properties of the sample analytes (i.e., components of the sample to be analyzed), and an indication of one or more substances present in the sample can be determined based on such identified properties of the sample analytes. In some cases, the sample to be analyzed must be a vapor for the detector to function as intended. In such cases, the vapor passes toward a detector, which measures one or more properties of the vapor (and detects the presence of a substance of interest based on these measured properties). For example, in an ion mobility spectrometer (IMS) or mass spectrometer (MS), ionized molecules can be identified based on their mobility or other properties in a carrier buffer gas or air. Detection devices for detecting the presence of dangerous or illicit substances, such as CWAs or TICs, are known. Summary of the Invention [Problem to be solved by the invention]

[0003] Aspects of the disclosure are provided in independent claims, with optional features provided in dependent claims. Aspects of the disclosure are provided in a mutually related manner, and features of one aspect may be applied to other aspects. [Means for solving the problem]

[0004] In one aspect, a flow inlet device for providing sample analyte vapor to a detector is provided. The device includes a sample receiving portion, a heating portion, a vapor pre-concentration portion, and a sampling inlet. The sample receiving portion is positioned to receive a gas flow carrying an aerosol sample analyte, and the heating portion is positioned to heat the aerosol sample analyte to provide sample analyte vapor. The device is positioned to provide the sample analyte vapor to both (i) the vapor pre-concentration portion and (ii) the detector via the sampling inlet.

[0005] Embodiments of the present disclosure may facilitate improved accuracy, reliability, and speed of detection of substances of interest in aerosol sample analytes. For example, aerosols present in small amounts may be detected more reliably after a larger amount of vaporized aerosol has accumulated in the vapor pre-concentration section. At the same time, aerosols present in large amounts may be detected simultaneously as vapor accumulates on the pre-concentration section. That is, the device may be configured to allow simultaneous sample detection (by the detector for vapor sampled via the sampling inlet) and sample accumulation (of sample vapor on the vapor pre-concentration section). For both vapor sampling and vapor accumulation, the vapor includes vaporized aerosol (e.g., vaporized within the inlet device by the heating section).

[0006] The device may be configured to provide a desorbed analyte vapor by desorbing sample analyte vapor accumulated on the vapor pre-concentrator. The device may be configured to provide the desorbed analyte vapor to the detector via the sampling inlet. The device may be configured to operate in (i) a first mode in which sample analyte vapor from the heated aerosol sample analyte is provided to the detector via the sampling inlet, and (ii) a second mode in which desorbed sample analyte from the vapor pre-concentrator is provided to the detector via the sampling inlet. When operating in the first mode, the device may be configured to simultaneously (provide a portion of the sample analyte vapor to the detector) and (accumulate a portion of the sample analyte vapor from the heated aerosol sample analyte) on the vapor pre-concentrator. The device may be configured to operate in the first mode for a selected period of time before switching to the second mode.

[0007] The device may be configured to reduce the flow rate of the gas through the device when switching from the first mode to the second mode. The device may be configured to inhibit the gas flow through the device when operating in the second mode. For example, in response to switching from the first mode to the second mode, the device may be configured to reduce (e.g., stop) the flow through the device, for example, by ceasing or reducing operation of an air mover of the device.

[0008] The apparatus may be configured to heat the vapor pre-concentrator section to desorb vapor from the vapor pre-concentrator section. The vapor pre-concentrator section may include a vapor pre-concentrator heating device. The pre-concentrator section may be configured to accumulate vapor on an outer surface of the pre-concentrator section. The outer surface may include a silicone material. The outer surface of the pre-concentrator section may at least partially surround the heating section (e.g., the outer surface may completely surround the heating section). Heating of the pre-concentrator section may be inhibited in the first mode.

[0009] The vapor pre-concentrator may be located between the sample receiving section and the sampling inlet. The heating section may be disposed along a flow path from the sample receiving section to the vapor pre-concentrator and the sampling inlet. The flow path through the device may include at least one bend. At least a portion of the vapor pre-concentrator may be located outside the bend. The device may be configured to provide sample vapor to an ion mobility spectrometer. The sampling inlet may include a pinhole inlet and / or a membrane jacket. The device may have two vapor pre-concentrator sections and / or two sampling inlets.

[0010] In one aspect, a detector configured to detect the presence of one or more substances of interest in a sample analyte vapor is provided. The detector includes an inlet device and a detection unit. The device includes a sample receiving unit, a heating unit, a vapor pre-concentration unit, and a sampling inlet. The sample receiving unit is positioned to receive a gas flow carrying an aerosol sample analyte, and the heating unit is positioned to heat the aerosol sample analyte to provide a sample analyte vapor. The device is positioned to provide the sample analyte vapor to both (i) the vapor pre-concentration unit and (ii) the detector via the sampling inlet. The detection unit is configured to detect the presence of one or more substances of interest in the sample analyte vapor received from the sampling inlet.

[0011] In one aspect, a method of providing a sample analyte vapor to a detector is provided, the method comprising receiving an aerosol sample analyte-carrying gas stream in an inlet device, heating the aerosol sample analyte to provide a sample analyte vapor, and providing the sample analyte vapor to both (i) the vapor pre-concentrator in the inlet device and (ii) the detector via the sampling inlet in the inlet device.

[0012] The sample analyte vapor may be accumulated on the vapor pre-concentrator and then provided to the vapor pre-concentrator for a selected period of time before being desorbed from the vapor pre-concentrator to provide a desorbed sample analyte vapor. The method may include providing the desorbed analyte vapor from the vapor pre-concentrator to the detector via the sampling inlet. Desorbing the sample analyte vapor from the vapor pre-concentrator to provide the desorbed analyte vapor may include heating the vapor pre-concentrator. Heating the vapor pre-concentrator may reduce the gas flow rate through the inlet device.

[0013] In one aspect, a method of operating a detector to detect the presence of one or more substances of interest in a sample analyte vapor is provided, the method comprising receiving a gas stream carrying an aerosol sample analyte, heating the aerosol sample analyte to provide a sample analyte vapor, providing the sample analyte vapor to both (i) a vapor pre-concentrator and (ii) the detector via a sampling inlet, and operating the detector to detect the presence of one or more substances of interest in the sample analyte vapor received from the sampling inlet.

[0014] Aspects of the present disclosure may include one or more computer program products having program instructions configured to program a controller to operate an inlet device and / or a detector to perform any of the methods disclosed herein. [Brief explanation of the drawings]

[0015] Some examples of the present disclosure will now be described, by way of example only, with reference to the following drawings.

[0016] [Figure 1] 1 shows a schematic diagram of an inlet device. [Figure 2] 1 shows a schematic diagram of an inlet device. [Figure 3] 1 shows a schematic diagram of an ion mobility spectrometer.

[0017] In the drawings, like reference numbers refer to like elements. DETAILED DESCRIPTION OF THE INVENTION

[0018] The present disclosure relates to a system and method for supplying sample analyte material vapor to a detector. An incoming gas stream from a sample to be analyzed passes through an inlet device. The gas stream passing through the inlet device may contain sample analyte material in the form of sample analyte material vapor and / or sample analyte material aerosol. The incoming gas stream is heated to generate sample analyte material vapor from the aerosol. A portion of the sample analyte material vapor in the inlet device is supplied to the detector via a sampling inlet in the inlet device, and a portion of the sample analyte material vapor in the inlet device is accumulated in a vapor pre-concentrator section in the inlet device. Thus, sample vapor accumulates in the vapor pre-concentrator section while being supplied to the detector via the sampling inlet. Periodically, the accumulated vapor in the vapor pre-concentrator section is desorbed therefrom, and a portion of the desorbed vapor is supplied to the detector via the sampling inlet. Because the vapor desorbed from the pre-concentrator section is at a higher concentration, sample analytes at relatively low concentrations in the gas flow are more reliably detected. Meanwhile, while the vapor analyte accumulates in the vapor preconcentrator, a high concentration of the analyte is still detectable at the detector.

[0019] An example of an inlet device will now be described with reference to FIG.

[0020] Figure 1 illustrates an inlet device 100. Device 100 includes a sample receiving section 110, a heating section 120, a vapor pre-concentration section 130, and a sampling inlet 140. Vapor pre-concentration section 130 includes a surface 131 and a desorption section 132. Arrows in Figure 1 illustrate an example of fluid flow through device 100.

[0021] Device 100 defines a flow path for the flow of fluid / aerosol through device 100. Device 100 can include a housing that defines (e.g., encloses) this flow path. For example, the housing provides a conduit through which the fluid and aerosol flow. Flow through device 100 is from an upstream location to a downstream location.

[0022] The sample receiving section 110 is located upstream of the device 100. The heating section 120 is located upstream of the vapor pre-concentration section 130 / sampling inlet 140. The heating section 120 is located between the sample receiving section 110 and the vapor pre-concentration section 130 / sampling inlet 140.

[0023] The heating section 120 is disposed across the flow path of the device 100. The heating section 120 may include a resistive heating section. The heating section 120 may provide aerosol heating. The heating section 120 may be composed of a plurality of electrical conductors (having a relatively high electrical resistance). The plurality of conductors may be arranged in a mesh or "grid" pattern. The conductors of the heating section 120 are disposed across the flow path (e.g., they may extend across the entire cross section of the conduit providing the flow path). For example, the heating section 120 may include a plurality of elongated conductive members extending across the sample receiving section 110. The conductive members may be arranged in a grid, such as a mesh or knitted mesh. The plurality of conductors may be positioned to at least partially block the flow of air through the inlet device 100 (e.g., between the sample receiving section 110 and the vapor pre-concentration section 120). The conductive members may be positioned so that the surface of the heating section in contact with the air flow is larger than the interior surface of the sample receiving section 110.

[0024] The vapor pre-concentration section 130 is disposed downstream of the heating section 120 and upstream of the sampling inlet 140. That is, the vapor pre-concentration section 130 is disposed between the heating section 120 and the sampling inlet 140. The vapor pre-concentration section 130 may be disposed adjacent to (e.g., immediately before) the sampling inlet 140. The separation between the vapor pre-concentration section 130 and the sampling inlet 140 may be set so that the vapor desorbed from the vapor pre-concentration section 130 is close to the sampling inlet 140.

[0025] Vapor pre-concentrator section 130 is comprised of surface 131 and desorber section 132. Desorber section 132 may be in the form of a heating section. Desorber section 132 is positioned proximate to surface 131 (e.g., so that desorber section 132 can heat surface 131). Surface 131 may at least partially surround desorber section 132 (e.g., completely surround desorber section 132). Surface 131 may be silicone-based. For example, vapor pre-concentrator section 130 may be formed from a heating element coated with silicone. Surface 131 is positioned within a flow path of device 100. For example, surface 131 may protrude into a conduit providing the flow path. Surface 131 is positioned as an obstacle to flow along the flow path.

[0026] The sampling inlet 140 is disposed downstream of the vapor pre-concentrator section 130. The sampling inlet 140 is for connecting the inlet device 100 (and the flow path therein) to a detector. When the inlet device 100 is connected to the detector, a flow path is provided from the sampling inlet 140 to the detector. That is, the sampling inlet 140 may provide a flow path connecting the inlet device 100 and the detector. The sampling inlet 140 may include a pinhole inlet. For example, the body of the inlet device 100 may be provided with a pinhole that defines a flow path (e.g., provides a conduit for fluid / aerosol flow). The sampling inlet 140 may optionally include a membrane covering.

[0027] Inlet device 100 is configured to allow gas to flow through a flow path through inlet device 100. For example, although not shown, device 100 can include an air mover that selectively provides flow through device 100. The air mover can include a pump or a fan. Additionally or alternatively, the air mover can be provided as a separate component from inlet device 100. Device 100 (e.g., an air mover) can be positioned to provide a flow of gas from sample receiving portion 110 to heating portion 120, vapor pre-concentration portion 130, and sampling inlet 140. Device 100 is configured such that the flow is heated by heating portion 120 and the heated flow is directed toward vapor pre-concentration portion 130 and sampling inlet 140.

[0028] The sample receiving portion 110 is configured to receive a sample analyte. The sample analyte comprises a sample material to be analyzed by a detector connected to the inlet device 100. The sample receiving portion 110 is configured to receive a gas flow containing the sample analyte. The sample analyte may be a vapor and / or an aerosol. The gas flow may carry the vapor and / or aerosol of the sample analyte material. The sample receiving portion 110 is configured to provide an opening for the sample analyte material to enter the flow path of the inlet device 100. For example, the sample receiving portion 110 may be configured to receive the sample analyte material from, for example, a swab.

[0029] The heating section 120 is configured to heat the sample analyte. In particular, the heating section 120 is arranged to heat the sample analyte aerosol to generate sample analyte vapor therefrom. That is, the heating section 120 is arranged to increase the proportion of sample analyte vapor. The heating section 120 is arranged to heat the material flowing from the sample receiving section 110 toward the vapor pre-concentration section 130 and the sampling inlet 140. The heating section 120 is configured to provide the sample analyte vapor from the sample analyte aerosol so that it becomes vapor when delivered to the vapor pre-concentration section 130 / sampling inlet 140.

[0030] Vapor pre-concentrator 130 is configured to accumulate sample analyte vapor. For example, the sample analyte vapor may be adsorbed onto surface 131 of vapor pre-concentrator 130. That is, vapor pre-concentrator 130 is positioned to collect a portion of the sample analyte vapor passing through inlet device 100. Vapor pre-concentrator 130 is configured to retain the sample analyte vapor on surface 131 (and to accumulate additional sample analyte vapor on surface 131 over time). Thus, vapor pre-concentrator 130 is configured to collect a portion of the sample analyte vapor that enters inlet device 100. As understood in the context of the present disclosure, the concentration of sample analyte in the gas passing through inlet device 100 may vary depending (among other things) on the sample being analyzed. At any given time, the concentration of sample analyte vapor within inlet device 100 that can be provided to the detector (via sampling inlet 140) may vary. Vapor pre-concentrator 130 is positioned to store sample analyte vapor and increase the concentration of the stored sample analyte vapor (eg, stored on surface 131 of vapor pre-concentrator 130).

[0031] Briefly, the vapor pre-concentrator is arranged to accumulate sample analyte material vapor in inlet device 100. The vapor pre-concentrator is selectively operable to desorb sample analyte material vapor therefrom and provide desorbed sample analyte vapor to inlet device 100. To this end, desorption unit 132 is configured to interact with surface 131 to desorb sample analyte vapor from surface 131. For example, desorption unit 132 may comprise a heating unit configured to heat surface 131 to desorb sample analyte vapor from surface 131 (to provide desorbed sample analyte vapor). As will be appreciated, desorption of such sample vapor from vapor pre-concentrator 130 increases the concentration of sample analyte vapor within inlet device 100 (due to the sudden influx of desorbed sample analyte vapor). That is, the vapor pre-concentrator may be configured to (i) accumulate sample analyte vapor and then (ii) exhaust the desorbed sample analyte vapor.

[0032] Sampling inlet 140 is configured to deliver sample analyte vapor from the flow path of inlet device 100 to the detector. Sampling inlet 140 may be selectively operable to allow / disallow flow to the detector. Sampling inlet 140 may be configured to prevent unintended flow to the detector. For example, if sampling inlet 140 includes a pinhole, device 100 (or a detector to which device 100 is connected) may be configured to apply negative pressure to draw vapor through the pinhole (when normal gas flow through inlet device 100 does not flow into sampling inlet 140). That is, device 100 (or a detector connected to device 100) may be configured to select when (and when not) to deliver sample analyte to the detector for analysis. Sampling inlet 140 operates to actively draw vapor from the flow path through inlet device 100 (and deliver that vapor to the detector).

[0033] Device 100 is configured to selectively use vapor pre-concentrator 130 to either (i) accumulate sample analyte vapor, or (ii) exhaust sample analyte vapor, and device 100 can be configured to switch between these two modes of operation (e.g., between accumulation and exhaust).

[0034] When used for sample analyte vapor accumulation, device 100 is configured to simultaneously (i) deliver sample analyte vapor to vapor pre-concentrator 130 and (ii) deliver sample analyte vapor to a detector via sampling inlet 140. That is, device 100 is configured to operate in a first mode (e.g., an accumulation mode) to simultaneously accumulate sample analyte vapor in vapor pre-concentrator 130 and deliver it to a detector (via sampling inlet 140). In this first mode of operation, a portion of the sample analyte vapor in inlet device 100 is stored in vapor pre-concentrator 130, and a portion is analyzed by the detector. Some or all of the sample vapor in inlet device 100 (that is accumulated in vapor pre-concentrator 130 or delivered to the detector) is aerosolized into inlet device 100 and then heated by heating device 120 to form a vapor.

[0035] When used for sample analyte vapor evacuation, device 100 is configured to (i) desorb vapor from vapor pre-concentrator 130 and provide the desorbed sample analyte vapor, and (ii) provide a portion of the desorbed sample analyte vapor to a detector for analysis. The desorption and providing the desorbed sample analyte vapor to the detector may be performed simultaneously or sequentially. For example, device 100 may be configured to desorb analyte vapor and simultaneously provide the vapor to the detector, or device 100 may be configured to first initiate analyte vapor desorption and then initiate providing the desorbed sample analyte vapor to the detector. That is, device 100 is configured to operate in a second mode (e.g., an evacuation mode) in which the sample analyte vapor stored in vapor pre-concentrator 130 is analyzed by a detector. In this second operating mode, the analyte vapor analyzed by the detector is from the vapor pre-concentration section 130 (e.g., in the first operating mode, the analyte vapor analyzed is not stored in the vapor pre-concentration section 130).

[0036] When operating in a first mode of operation, a flow is provided through inlet device 100. In the first mode of operation, device 100 may be configured to provide a flow of sample analyte material vapor from heating section 120 toward vapor pre-concentration section 130 / sampling inlet 140. Vapor pre-concentration section 130 is positioned to receive a portion of this sample analyte vapor, and sampling inlet 140 may be configured to capture a portion of this sample analyte vapor and provide the vapor to a detector. The remaining sample analyte vapor continues along the flow path beyond sampling inlet 140 and toward an outlet of device 100. In the first mode of operation, desorbing section 132 may be inactive (e.g., heating section turned off). Thus, vapor pre-concentration section 130 is configured to promote accumulation of sample analyte vapor in the first mode of operation, prioritizing accumulation over discharge.

[0037] When operating in the second operating mode, the flow rate through the inlet device of device 100 is reduced or completely stopped. In the second operating mode, the flow rate of sample analyte vapor through the inlet device is reduced. For example, the air mover is deactivated. Desorption section 132 is configured to desorb sample analyte vapor from vapor pre-concentration section 130. The desorbed sample analyte vapor is less likely to flow downstream. Sampling inlet 140 can be operated to actively draw in a portion of this desorbed sample analyte vapor and deliver it to the detector. In this mode, vapor pre-concentration section 130 can be configured to promote the removal of sample analyte vapor rather than its accumulation.

[0038] Although not shown, device 100 (or a detector connected to device 100) may include a controller. The controller may be configured to control the operation of components of inlet device 100 and / or the detector. For example, the controller may be configured to control heating unit 120 to selectively heat the sample analyte aerosol. The controller may be configured to control desorption to selectively desorb sample vapor from vapor pre-concentrator unit 130. The controller may be configured to control the operation of an air mover to provide or restrict flow rate through inlet device 100. The controller may be configured to control the operation of the detector and / or sampling inlet 140 to actively draw vapor through sampling inlet 140 (e.g., apply negative pressure to sampling inlet 140).

[0039] The controller is configured to control the operation of these components to operate device 100 in a first mode and a second mode. For example, the controller is configured to control the operation of various components to switch between the first mode and the second mode. The controller is configured to operate device 100 in the first mode for a selected period of time (e.g., before switching device 100 to the second mode).

[0040] The controller is configured to control operation in a first mode, specifically, (i) activating the air mover to generate airflow through inlet device 100, (ii) activating heating element 120 to generate sample analyte vapor from the sample analyte aerosol, (iii) deactivating desorber element 132 to allow sample analyte vapor to accumulate in vapor pre-concentrator element 130, and (iv) actively drawing a portion of the sample analyte vapor from inlet device 100 to a detector through sampling inlet 140.

[0041] The controller may be configured to control operation in the second mode, in which (i) the air mover is inactive and / or produces a reduced flow rate through the inlet device 100 (compared to the first mode), (ii) the heating element 120 is optionally inactive, (iii) the desorption element 132 is active to promote desorption of sample analyte vapor (e.g., such that the desorbed sample analyte vapor resides within the inlet device 100 proximate the sampling inlet 140), and (iv) some sample analyte vapor is actively drawn from the inlet device 100 through the sampling inlet 140 to be delivered to the detector.

[0042] In operation, the inlet device 100 begins operating in its first mode of operation.

[0043] In this first mode of operation, gas from a sample to be analyzed is received at the sample receiving portion 110 of the inlet device 100. This gas contains an aerosol of some sample analyte material. The gas and the aerosol of sample analyte material contained therein flow along a flow path within the inlet device 100. The heating portion 120 heats this flow from the sample receiving portion 110. As a result of the heating, some of the aerosol of sample analyte material evaporates, producing a vapor of sample analyte material. This vapor of sample analyte material flows along a flow path within the inlet device 100. A portion of this sample analyte vapor accumulates on the surface 131 of the vapor pre-concentration portion 130. This accumulated sample analyte vapor remains on the surface 131 (e.g., as long as the desorption portion 132 is inactive). A portion of the sample analyte vapor within the inlet device 100 (i.e., that which does not accumulate on the surface 131 of the vapor pre-concentration portion 130) is provided to a detector for analysis. This is done by actively drawing vapor from the flow path of inlet device 100 through sampling inlet 140, for example by applying a negative pressure. The accumulation of vapor in vapor pre-concentrator 130 and the sampling of the vapor through sampling inlet 140 occur simultaneously. Thus, while analysis of some sample analyte vapors from inlet device 100 is being performed, other sample analyte vapors within inlet device 100 are being accumulated in vapor pre-concentrator 130.

[0044] Operation in this first mode can continue for a selected period of time. During this period, gas may continue to flow through the flow path of inlet device 100. Thus, sample analytes (e.g., aerosols) continue to enter inlet device 100, vaporize into sample analyte vapor, and then accumulate in vapor pre-concentrator 130. Over time, vapor pre-concentrator 130 effectively stores the sample analyte vapor at a higher concentration than is present in the gas flow through inlet device 100. The selected period of time may be set to allow time to elapse until a sufficient amount of sample analyte vapor has accumulated in vapor pre-concentrator 130 (e.g., to allow a detector to identify relevant substances from the resulting desorbed sample analyte vapor).

[0045] During this initial mode of operation, the detector analyzes one or more sample portions obtained through the sampling inlet 140 (and the flow path of the inlet device 100). Based on the analysis of these one or more sample portions, an indication of the presence or absence of a substance of interest in the sample can be identified. If a substance of interest is present in a relatively large amount in the sample, a sample analyte vapor indicative of that substance will likely be obtained from the inlet device 100 (via the sampling inlet 140) and detected in the analysis during the initial mode of operation. As a result, substances of interest that are present in large amounts can be reliably detected by the detector. However, substances of interest that are present in relatively small amounts in the sample may be less likely to be reliably identified by the detector due to the much lower concentrations of sample vapor analytes for these substances.

[0046] To allow for more reliable detection of these substances, the device 100 may be switched to operate in a second mode.

[0047] In the second mode of operation, the flow rate through inlet device 100 is reduced. For example, the air mover may be turned off (or set to a low power level). As a result, the airflow through the flow passages of inlet device 100 is significantly reduced compared to the first mode of operation. Optionally, heating unit 120 may be turned off (or at a reduced power level) during operation in the second mode (e.g., because fewer or no aerosols of sample analyte material are vaporized through heating unit 120). Desorption unit 132 is turned on. During operation, desorption unit 132 desorbs sample analyte vapor from vapor pre-concentration unit 130. For example, desorption unit 132 begins heating surface 131 of vapor pre-concentration unit 130. Operation of desorption unit 132 desorbs vapor from vapor pre-concentration unit 130, producing desorbed sample analyte vapor.

[0048] Operation of the desorbing section 132 can produce a vapor cloud of desorbed sample analyte material. Because the vapor pre-concentrator section 130 is located adjacent to the sample inlet 140 and the airflow rate through the collection device 100 is significantly reduced, a high concentration of desorbed sample analyte material vapor can be present near the sample inlet 140. One or more portions of the sample vapor are then delivered (e.g., by applying a negative pressure) through the sampling inlet 140 to the detector. Thus, the portion analyzed by the detector can contain a relatively high concentration of desorbed sample analyte material vapor. Because the desorbed sample analyte vapor has accumulated over a long period of time, it tends to be enriched in substances of potential interest present in the sample being analyzed. Therefore, the detector can be operated to analyze vapor samples with a high proportion of desorbed sample analyte vapor. This allows for more reliable detection of substances (e.g., aerosols) present in relatively small amounts in the sample being analyzed.

[0049] After the vapor sample to be analyzed has been obtained, the device 100 can be returned to operation in the first mode, which includes reactivating the heating section 120 (if it was turned off), turning off the desorbing section 132, and increasing the flow rate through the inlet device 100.

[0050] The above-described apparatus (and corresponding method of operation) may enable the simultaneous detection of relatively high concentrations of a substance of interest (i.e., a first mode of operation) and relatively low concentrations of a substance of interest (i.e., a second mode of operation). That is, when operating in the first mode of operation, the detector detects substances of interest (especially those present in high concentrations). While this is occurring, some substances of interest (including those present in low concentrations) may accumulate in the vapor pre-concentrator 130. The apparatus 100 may then switch to a second mode of operation in which high-concentration sampling (i.e., desorbed sample analyte vapor) is performed. The low-concentration substances may then be identified based on analysis of this high-concentration sample.

[0051] Figure 2 shows another inlet device. The device in Figure 2 is similar to the device in Figure 1. Figure 1 shows an example of an inlet device shown in cross-section from a side view. Figure 2 shows a portion of the inlet device in plan view. The arrows indicate the direction of flow through the inlet device.

[0052] As can be seen in FIG. 2 , the introduction device defines a tortuous flow path for the fluid / aerosol flow. The flow path includes at least one bend (two are shown in FIG. 2 ). The device also includes two vapor pre-concentration sections 130 and two sampling inlets 140. Each vapor pre-concentration section 130 is positioned with an associated sampling inlet 140. The arrangement of each vapor pre-concentration section 130 / sampling inlet 140 is the same as that described above with reference to FIG. 1 . That is, each vapor pre-concentration section 130 is positioned upstream of and adjacent to its corresponding sampling inlet 140. Furthermore, each vapor pre-concentration section 130 is positioned in a bend in the flow path. In particular, each vapor pre-concentration section 130 is positioned in an outer region of the bend (e.g., radially outward of the bend). Each vapor pre-concentration section 130 may be positioned in a region of the bend immediately following a straight section of the flow path. Each vapor pre-concentration section 130 may be positioned in a region of the inlet device where the flow is more turbulent. Each sampling inlet 140 may be located immediately downstream of its vapor pre-concentrator section 130 .

[0053] The operation of the system is similar to that described above, with two operating modes simultaneously implemented for each of the two vapor pre-concentrator / sampling inlet pairs: each vapor pre-concentrator 130 and sampling inlet 140 operates in a first operating mode for a selected period of time, after which both vapor pre-concentrator 130 / sampling inlet 140 switch to a second operating mode.

[0054] The examples described herein relate to a detector sample introduction device 100. The inlet device 100 is configured to supply a sample analyte vapor to a detector. The device 100 is configured to vaporize an aerosol of sample analyte material to produce a sample analyte vapor and supply a portion of the sample analyte vapor to the detector via a sampling inlet 140. Some of the vaporized sample analyte vapor is supplied directly to the detector, and some is supplied by being accumulated in a vapor preconcentrator 130 and subsequently desorbed therefrom. In both the first and second modes of operation, the sample analyte supplied to the detector is a vapor.

[0055] It will be understood that the context of the present disclosure need not be limited to a particular type of detector. The detector is configured to detect the presence of one or more substances of interest in a sample. The detector can include an ion analyzer. The detector can include a spectrometer. For example, the detector can include an ion mobility spectrometer or a mass spectrometer. The inlet device herein is particularly useful in supplying sample vapor to an ion mobility spectrometer, an example of which is described with reference to FIG. 3.

[0056] FIG. 3 shows a cross-sectional view of a portion of the detector of an ion mobility spectrometer (IMS) 280.

[0057] 3 includes an ionization section 288 separated from a drift chamber 292 by a gate 282. The gate 282 can control the passage of ions from the ionization section 288 to the drift chamber 292. As shown, the IMS 280 includes an inlet 281 for material introduced into the ionization device 288 from a sample of interest (e.g., via the sampling inlet 140 of the inlet device 100).

[0058] 3, a drift chamber 292 is positioned between the ionization region 288 and the detector 287, and ions pass through the drift chamber 292 to reach the detector 287. The drift chamber 292 may have a series of drift electrodes 283, 284 that apply a voltage profile along the drift chamber 292 to move ions from the ionization region 288 along the drift chamber 292 towards the detector 287.

[0059] IMS 280 may be configured to provide a flow of drift gas in a direction generally opposite to the path of travel of ions to detector 287. For example, the drift gas may flow next to detector 287 toward gate 282. As shown, drift gas may be passed through the drift chamber using drift gas inlet 289 and drift gas outlet 290. Examples of drift gases include, but are not limited to, nitrogen, helium, air, recycled air (e.g., purified and / or dried air), etc.

[0060] The detector 287 may be connected to send a signal to the detector control 294. The current from the detector 287 may be used by the control 294 to infer that an ion has reached the detector 287, and a characteristic of the ion may be determined based on the time it takes for the ion to travel from the gate 282 through the drift chamber 292 to reach the detector 287. An example detector 287 is configured to provide a signal indicating that an ion has reached the detector 287. For example, the detector may include a conductive electrode (e.g., a Faraday plate).

[0061] The electrodes 283, 284 may be positioned to direct ions towards the detector 287. For example, the drift electrodes 283, 284 may comprise rings positioned around the drift chamber 292 to focus ions onto the detector 287. While the example in Figure 3 includes only two drift electrodes 283, 284, in some examples multiple electrodes may be used, or a single electrode may be used in combination with the detector 287 to apply an electric field to direct ions towards the detector 287.

[0062] Spectrometer 280 has ion-modifying electrodes 285, 286 disposed within the drift chamber, although it should be understood that in the context of this specification these electrodes may not be included.

[0063] 3, power supply 293 is connected to be controlled by control unit 294. Power supply 293 may also be connected to provide a voltage to ionization unit 288 to ionize materials from the sample. In one embodiment, power supply 293 is connected to gate electrode 282 to control the movement of ions from the ionization chamber to drift chamber 292. Power supply 293 may be connected to drift electrodes 283, 284 to provide a voltage profile to move ions from ionization unit 288 toward detector 287.

[0064] As described above, the drift electrodes 283, 284 provide a voltage profile that moves ions along the drift chamber, causing them to move from the ionization region toward the detector. As shown in Figure 3, the first ion modifying electrode 285 and the second ion modifying electrode 286 are spaced apart along the direction of ion movement.

[0065] The spectrometer and voltage supply may be housed in a common housing. In spectroscopic measurements, ion counts are measured by peaks in the spectrum, and the height of the peaks can be an indication of the number of ions reaching the detector at a particular time. Ions produced by reactions of the substance of interest with neutral molecules are called "daughter ions," and the ions that produce the daughter ions are called "parent ions."

[0066] As noted above, other types of detectors may be used. For example, mass analyzers such as time-of-flight mass analyzers may be used. In such mass analyzers, the mass-to-charge ratio of ions may be estimated from their time of flight in a vacuum. In other types of mass analyzers, ions may be separated based on their mass-to-charge ratio by other methods, such as deflection under an electric or magnetic field.

[0067] The detection device, including the detector and the inlet device, may be mounted in a portable unit, for example the detection device may be handheld.

[0068] In the context of the present disclosure, it will be understood that the vapor pre-concentrator 130 may be provided in any suitable form. To this end, the vapor pre-concentrator 130 includes a portion for accumulating sample vapor (e.g., surface 131) and a member for promoting desorption of the sample vapor therefrom (e.g., desorption portion 132). The desorption portion 132 may include a heating device for inducing desorption by heating, although other forms of the desorption portion 132 may also be provided. For example, the desorption portion 132 may be configured to induce desorption of the sample vapor therefrom by applying radiation, pressure, vibration, or the like to the surface 131. The surface 131 may include an adsorbent material (e.g., an adsorbent coating) to which the sample analytes bind during the adsorption phase. The surface 131 may have an adsorbent coating. For example, the vapor pre-concentrator 130 may include a heating element having an adsorbent coating. The surface 131 (e.g., an adsorbent coating) may be silicone-based.

[0069] As described herein, the heating element 120 may be provided by a resistive heater in the form of a conductive mesh grid disposed across the inlet flow path. However, it should be noted that this is not limiting and other types of heating devices may be provided. For example, radiant heaters (e.g., infrared heaters) may be used. Similarly, in the illustrated example, an air mover is provided to control the flow of air through the inlet device. It should be noted that the air mover may be provided as part of the inlet device or as a separate component. For example, the air mover may be provided as a component connecting the sample to the inlet device (e.g., to blow air from the sample into the inlet device) or may be located downstream of the sampling inlet (e.g., to draw air into the inlet device).

[0070] From the above description, it is understood that the illustrated examples are merely examples and include features that can be generalized, omitted, or substituted as described and claimed herein. With reference to the drawings generally, it will be understood that schematic functional block diagrams have been used to illustrate the functionality of the systems and devices described herein. Furthermore, processing functions may be provided by devices supported by electronic devices. However, functions need not necessarily be divided in this manner, and no particular hardware structure other than that described and claimed below is implied. One or more functions of the illustrated elements may be further subdivided or distributed throughout the devices of the present disclosure. In some examples, one or more functions of the illustrated elements may be integrated into a single functional unit.

[0071] In the context of this disclosure, a skilled reader will understand that each example described herein can be implemented in a variety of different ways. Any feature of any aspect of this disclosure can be combined with other aspects of the disclosure. For example, method aspects can be combined with apparatus aspects, and features described with reference to the operation of specific elements of an apparatus can also be provided in methods that do not use those specific types of apparatus. Furthermore, each feature in each example is separable from other features with which it is combined, unless other features are explicitly described as essential to its operation. These separable features can, of course, be combined with other features in the described example or with other features or combinations of features in other examples described herein. Equivalents and variations not described above may also be used.

[0072] Certain functions of the methods described herein may be implemented in hardware, and one or more functions of an apparatus may be implemented in method steps. In the context of this specification, it will be understood that the methods described herein need not be performed in the order described or in the order shown in the figures. Thus, aspects of this specification described with reference to a product or apparatus are also intended to be implemented as a method, and vice versa. The methods described herein may be implemented in a computer program, hardware, or any combination thereof. Computer programs include software, middleware, firmware, and any combination thereof. Such programs may be provided as signals or network messages and recorded on computer-readable media (e.g., tangible computer-readable media capable of storing computer programs in a non-transitory form). Hardware includes computers, handheld devices, programmable processors, general-purpose processors, application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), and arrays of logic gates.

[0073] Other examples and variations of the present disclosure will be apparent to those skilled in the art in light of this specification.

Claims

1. an inlet device for providing sample analyte vapor to a detector, comprising: a sample receiving section; A heating unit; a vapor pre-concentration section; Sampling Inlet Equipped with the sample receiving portion is positioned to receive a gas flow carrying an aerosol sample analyte, and the heating portion is positioned to heat the aerosol sample analyte to provide a sample analyte vapor; An apparatus configured to provide the sample analyte vapor to both (i) the vapor pre-concentrator and (ii) the detector via the sampling inlet.

2. 10. The device of claim 1, configured to provide a desorbed analyte vapor by desorbing sample analyte vapor accumulated on the vapor pre-concentrator.

3. 3. The apparatus of claim 2, configured to provide the desorbed analyte vapor to the detector via the sampling inlet.

4. 4. The apparatus of claim 3, (i) a first mode in which sample analyte vapor from the heated aerosol sample analyte is provided to the detector via the sampling inlet; (ii) a second mode in which desorbed sample analytes from the vapor pre-concentrator are provided to the detector via the sampling inlet; 20. An apparatus configured to operate in accordance with claim 19.

5. 5. The apparatus of claim 4, configured to operate in the first mode for a selected period of time before switching to the second mode.

6. 6. An apparatus according to claim 4 or 5, configured to reduce the gas flow through the apparatus when switching from the first mode to the second mode.

7. 7. The apparatus of claim 6, configured to restrict the gas flow through the apparatus when operating in the second mode.

8. 8. The apparatus of claim 2, configured to heat the vapor pre-concentration section to desorb from the vapor pre-concentration section.

9. 9. The apparatus of claim 8, wherein the vapor pre-concentrator section includes a vapor pre-concentrator heater.

10. 10. The apparatus of claim 9, wherein the pre-concentrator section is configured to accumulate vapor on an outer surface of the pre-concentrator section, and optionally the outer surface comprises a silicone material.

11. 11. The apparatus of claim 10, wherein the outer surface of the pre-concentration section at least partially surrounds the heating section.

12. 12. The apparatus according to claim 8, wherein heating of the pre-concentration section is suppressed in the first mode.

13. 13. The apparatus according to claim 1, wherein the vapor pre-concentrator is provided between the sample receiver and the sampling inlet.

14. 14. The apparatus according to claim 1, wherein the heating section is disposed along a flow path extending from the sample receiving section to the vapor pre-concentration section and the sampling inlet.

15. 15. A device according to any preceding claim, wherein the flow path through the device comprises at least one bend.

16. 16. The apparatus of claim 15, wherein at least a portion of the vapor pre-concentrator section is located outside the bend.

17. 17. An apparatus according to any preceding claim, arranged to provide sample vapor to an ion mobility spectrometer, and / or wherein the sampling inlet comprises a pinhole inlet and / or a membrane jacket.

18. 18. An apparatus according to any one of claims 1 to 17, comprising two vapor pre-concentration sections and / or two sampling inlets.

19. a detector configured to detect the presence of one or more substances of interest in a sample analyte vapor, the detector comprising an inlet device and a detection portion; The inlet device comprises: a sample receiving section; A heating unit; a vapor pre-concentration section; Equipped with a sampling inlet, the sample receiving portion is positioned to receive a gas flow carrying an aerosol sample analyte, and the heating portion is positioned to heat the aerosol sample analyte to provide a sample analyte vapor; the device is configured to provide the sample analyte vapor to both (i) the vapor pre-concentrator and (ii) the detector via the sampling inlet; the detection portion is configured to detect the presence of one or more substances of interest in the sample analyte vapor received from the sampling inlet; Detector.

20. 1. A method of subjecting a sample analyte vapor to a detector, comprising: receiving a gas flow carrying an aerosol sample analyte in an inlet device; heating the aerosol sample analyte to provide a sample analyte vapor; subjecting the sample analyte vapor to both (i) a vapor pre-concentrator in the inlet device and (ii) the detector via a sampling inlet in the inlet device; A method having the following.

21. 21. The method of claim 20, wherein the sample analyte vapor accumulated on the vapor pre-concentration unit is provided to the vapor pre-concentration unit during a selected period before the sample analyte vapor desorbs from the vapor pre-concentration unit to provide desorbed analyte vapor.

22. 22. The method of claim 21, comprising providing the desorbed analyte vapor from the vapor pre-concentrator to the detector via the sampling inlet.

23. 23. The method of claim 22, wherein desorbing the sample analyte vapor from the vapor pre-concentrator to provide the desorbed analyte vapor comprises heating the vapor pre-concentrator; When the vapor pre-concentration section is heated, the flow rate of gas through the inlet device is reduced. method.

24. 1. A method of operating a detector to detect the presence of one or more substances of interest in a sample analyte vapor, comprising: receiving a gas flow carrying an aerosol sample analyte; heating the aerosol sample analyte to provide a sample analyte vapor; subjecting the sample analyte vapor to both (i) a vapor pre-concentrator and (ii) the detector via a sampling inlet; operating the detector to detect the presence of one or more substances of interest in a sample analyte vapor received from the sampling inlet; A method having the following.

25. A computer program product having program instructions configured to program a controller to operate the inlet device and / or the detector to perform the method according to any of claims 20 to 24.

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