Sprayer assembly

Abstract

A nebulizer assembly for an ion source is disclosed. The nebulizer includes a capillary tube having an outlet, a sheath for the capillary tube, and a resilient member. The sheath is movable relative to the capillary tube between a first position in which the sheath covers the outlet of the capillary tube and a second position in which the outlet of the capillary tube is exposed. The resilient member provides a restoring force to restore the position of the sheath to or toward the first position when the sheath is moved from the first position toward or toward the second position.

Description

[0001] This application is a divisional application of patent application No. 202180007081.6 filed on January 22, 2021, entitled "Sprayer Assembly".

[0002] Cross-references to related applications

[0003] This application claims priority and benefit to U.S. Provisional Patent Application No. 62 / 965268, filed January 24, 2020; U.S. Provisional Patent Application No. 63 / 071081, filed August 27, 2020; and United Kingdom Patent Application No. 2014233.7, filed December 10, 2020. The entire contents of these applications are incorporated herein by reference. Technical Field

[0004] This invention generally relates to ion sources, and more particularly to nebulizer assemblies for ion sources. Background Technology

[0005] Desorption electrospray ionization (“DESI”) is a form of ambient ionization in which a nebulizer device is used to direct a spray of solvent droplets onto the surface of the sample to be analyzed. The solvent droplets are used to desorb the analyte material from the sample surface. The analyte material released (desorbed) from the sample can then be collected and analyzed by analytical instruments such as mass and / or ion mobility spectrometers.

[0006] Figure 1 A typical DESI sprayer 10 is shown. (As shown...) Figure 1 As shown, the atomizer 10 includes a solvent capillary 12 and a gas capillary 13. The solvent capillary 12 is coaxially arranged within the gas capillary 13, with the solvent outlet 12A of the solvent capillary 12 extending beyond the distal end of the gas capillary 13. The solvent flow 14 supplied to the solvent capillary 12 is charged by means of a high-voltage source 18 and guided toward the sample 1 with the assistance of the atomizing gas flow 15 supplied to the gas capillary 13.

[0007] The resulting (primary) charged droplet 11 spray is able to desorb the analyte material from the surface of sample 1, and the (secondary) droplets carrying the desorbed ionized analyte can then travel via transfer capillary 20 to the atmospheric pressure interface 22 of an analytical instrument such as a mass and / or ion mobility spectrometer (not shown).

[0008] The applicant has recognized that the solvent capillary 12 may be relatively fragile and therefore easily damaged. The applicant has proposed an improved arrangement in WO 2018 / 189534, the entire contents of which are incorporated herein by reference, in which the solvent outlet 12A of the solvent capillary 12 is arranged behind a nozzle or shroud.

[0009] However, the inventors believe that there is still room for improvement for the ion source and for the ion source sprayer assembly. Summary of the Invention

[0010] According to a first aspect, a sprayer assembly is provided, the sprayer assembly comprising:

[0011] Capillary tube, the capillary tube having an outlet;

[0012] Sheath for the capillary; and

[0013] Elastic components;

[0014] The component is configured such that the sheath is movable relative to the capillary between a first position where the sheath covers the outlet of the capillary and a second position where the outlet of the capillary is not covered by the sheath; and

[0015] The component is configured such that when the sheath moves from the first position to or toward the second position, the elastic member provides a restoring force to restore the position of the sheath to or toward the first position.

[0016] Various embodiments relate to an ion source nebulizer assembly, such as a desorption electrospray ionization (“DESI”) nebulizer assembly. The assembly includes a (solvent) capillary and a sheath (tight-fit cap) for the capillary, the sheath serving as a protective cap for the (relatively more vulnerable) capillary. The sheath is movable relative to the capillary between a first position in which the sheath covers and thus protects the (solvent release) outlet or tip of the capillary, and a second position in which the sheath does not cover the outlet (tip), for example, where the outlet is exposed (for normal use). The assembly also includes an elastic member, such as a compression spring, for biasing the sheath toward the first position in which the outlet is covered (protected) by the sheath (where the outlet is not exposed).

[0017] The inventors have recognized that while arranging a solvent capillary behind a nozzle, as described, for example, in WO 2018 / 189534, can provide protection for the capillary during normal use, it may be desirable to remove the nozzle, for example, to clean the nozzle, or to replace the nozzle with a different nozzle, for example, that may have different sizes and / or constructions. This allows the capillary, particularly the solvent dispensing tip of the capillary, to be exposed and vulnerable to damage. Furthermore, the capillary can be a “consumable” item that is typically replaced relatively frequently, and therefore transported and installed independently of protective elements such as the nozzle. Consequently, the capillary may be vulnerable to damage during transport and installation. Additionally, the solvent dispensing tip of the capillary can be relatively sharp, thus associated with a risk of injury.

[0018] By providing a sheath for the capillary, the capillary can be protected, for example, during transport and installation. Furthermore, the risk of injury can be reduced. Additionally, by biasing the sheath relative to the capillary with an elastic member, the sheath can retract to expose the outlet for normal use, but then automatically extend to cover and thus protect the outlet, for example, when the nozzle is removed.

[0019] Therefore, it should be understood that various embodiments provide an improved ion source sprayer assembly.

[0020] The component can be configured such that the elastic member elastically deforms when the sheath moves from the first position to or toward the second position.

[0021] The elastic member may be a spring, such as a compression spring. The assembly may be configured such that the compression spring is compressed when the sheath moves from the first position toward or toward the second position.

[0022] The compression spring may surround the capillary. The assembly may be configured such that the compression spring can be compressed between a collar disposed on the capillary and the sheath (inner shoulder).

[0023] The sheath may include a cavity, and the elastic member (compression spring) may be disposed within the cavity of the sheath. This retains and protects the elastic member and allows the capillary, sheath, and elastic member to be provided together in a cylindrical form.

[0024] The sheath can be formed from any suitable material such as metal and / or ceramic and / or plastic such as PEEK (polyether ether ketone) or PPS (polyphenylene sulfide).

[0025] The sheath may be insulating. For example, the sheath may be formed of an insulating material such as plastics like PEEK (polyetheretherketone) or PPS (polyphenylene sulfide). Alternatively or alternatively, the sheath may have an insulating coating, such as a plastic coating. For example, the sheath may be formed of a metal with an insulating coating.

[0026] The sheath may include one or more gas outlets configured to release gas, for example, such that the gas interacts with (atomized) solvent released from the outlet of the capillary to produce a spray of solvent droplets.

[0027] The sheath may include one or more gas conduits. The one or more gas conduits may be configured to connect one or more gas inlets of the sheath to one or more gas outlets. Atomizing gas can thus flow from the one or more gas inlets to the one or more gas outlets.

[0028] The gas conduit can be inside the sheath or formed on the outside of the sheath.

[0029] The sheath may include an axial orifice configured to retain the capillary, and the one or more gas conduits may each be arranged parallel to the axial orifice.

[0030] The sheath can be formed as a single (integrated) part, or it can be formed from multiple parts. For example, the sheath can be formed from a main sheath body and an insert disposed within the main sheath body. The cavity can be formed in the main sheath body. The axial orifice and the one or more gas conduits can be formed in the sheath insert.

[0031] The capillary can be formed from a metal such as stainless steel.

[0032] The outlet of the capillary may be tapered. The outlet of the capillary may be configured to release solvent (droplets).

[0033] The component may include a sprayer assembly body. The capillary, the sheath, and the resilient member may be removably attached to the body.

[0034] The capillary, the sheath, and the elastic member can be configured as a cylinder, and the cylinder can be removably attached to the body. The body may include an orifice configured to receive the cylinder.

[0035] The component may also include a removable nozzle. The nozzle can be removably attached to the body.

[0036] The nozzle may include an orifice. Solvent (droplets) dispensed from the capillary may be arranged to pass through the orifice of the nozzle.

[0037] The component can be configured such that installing the nozzle moves the sheath to the second position, while removing the nozzle moves the sheath to the first position.

[0038] The component can be configured such that when the nozzle is attached to the body, the cylinder (shroud) is held within the body.

[0039] According to another aspect, a sprayer assembly is provided, the sprayer assembly comprising:

[0040] Sprayer assembly body;

[0041] Capillary tube, the capillary tube having an outlet;

[0042] Sheath for the capillary; and

[0043] A nozzle, which is removably attached to the body;

[0044] The component is configured such that the sheath is movable relative to the capillary between a first position where the sheath covers the outlet of the capillary and a second position where the outlet of the capillary is not covered by the sheath (where the sheath does not cover the outlet of the capillary); and

[0045] The component is configured such that attaching the nozzle to the body moves the sheath to the second position, while removing the nozzle from the body moves the sheath to the first position.

[0046] The components described in this aspect may, as appropriate, have any one or more or each of the optional features described herein with respect to other aspects.

[0047] The component according to this aspect may include an elastic member and may be configured such that when the sheath moves from the first position to or toward the second position, the elastic member provides a restoring force for restoring the position of the sheath to or toward the first position.

[0048] In various aspects and implementations, the component may be configured such that when the nozzle is attached to the body, the nozzle pushes the sheath to the second position.

[0049] The component can be configured such that when the nozzle is connected to the body, the sheath is held in the second position.

[0050] The component can be configured such that when the nozzle is removed from the body, the restoring force causes the sheath to move toward or towards the first position.

[0051] The sheath can be configured to guide the nozzle to be coaxially aligned with the capillary when the nozzle is attached to the body.

[0052] According to another aspect, a sprayer assembly is provided, the sprayer assembly comprising:

[0053] Sprayer assembly body;

[0054] Capillary;

[0055] Guide, the guide being configured to retain the capillary; and

[0056] A nozzle, which is removably attached to the guide;

[0057] The guide is configured to guide the nozzle to be coaxially aligned with the capillary when the nozzle is attached to the guide.

[0058] The components described in this aspect may, as appropriate, have any one or more or each of the optional features described herein with respect to other aspects.

[0059] The inventors have recognized that sprays produced by a sprayer with a nozzle may be particularly sensitive to alignment (centering) between the capillary and the nozzle, and therefore can improve spray reproducibility by providing a nozzle guide.

[0060] The alignment (centering) can be achieved by aligning (positioning) the nozzle (orifice) (coaxially) with the capillary (outlet) (positioning in a straight line).

[0061] The nozzle may include an orifice configured to be coaxially mounted above the nozzle guide (shroud).

[0062] The capillary tube may be arranged coaxially with the nozzle guide (shroud), for example, held in the central axial orifice of the nozzle guide (shroud), and the nozzle orifice may be arranged coaxially with the nozzle orifice, for example, on the central axis of the nozzle.

[0063] The outlet end of the nozzle guide (shroud) may have a conical or truncated conical shape, and the inner surface of the nozzle orifice may have a complementary conical or truncated conical shape.

[0064] The nozzle can be removably attached to the guide via a threaded or bayonet fitting.

[0065] The inventors have recognized that sprays produced by a sprayer with a nozzle can be particularly sensitive to the distance between the nozzle orifice and the capillary outlet. Furthermore, it has been recognized that the use of bayonet fittings can reduce this variability in distance, thus improving spray reproducibility.

[0066] The bayonet assembly may include a connector body and one or more lugs. The body may include one or more recesses arranged to receive the one or more lugs.

[0067] The atomizer assembly can be configured such that the distance between the nozzle orifice and the capillary outlet is adjustable, for example, controllably adjustable. Some or all of the rear surface of the connector body can be oblique, inclined, and / or curved.

[0068] The component may include a nozzle assembly, the nozzle assembly including the nozzle and the threaded or bayonet fitting, wherein the nozzle is removable from the threaded or bayonet fitting.

[0069] The nozzle can be fastened to the threaded or bayonet fitting.

[0070] According to another aspect, a sprayer assembly is provided, the sprayer assembly comprising:

[0071] Sprayer assembly body;

[0072] A cylinder, the cylinder housing a capillary; and

[0073] A nozzle, which is removably attached to the body;

[0074] The components are configured such that when the nozzle is attached to the body, the cylinder can be held within the body (through the nozzle).

[0075] The components described in this aspect may, as appropriate, have one or more or each of the optional features described herein with respect to other aspects.

[0076] By providing a removable sleeve to house the capillary, capillary installation becomes more straightforward and user-friendly, and the risk of capillary damage during installation is reduced.

[0077] The body may include one or more supply ports. The component may be configured such that when the cylinder is held within the body, the one or more supply ports are coupled to one or more corresponding ports of the cylinder.

[0078] The main body may include a solvent supply port. The main body may include a gas supply port. The main body may include a high voltage supply port.

[0079] The component may be configured such that when the cartridge is held within and / or connected to the body, the solvent supply port is coupled to the capillary.

[0080] The component may be configured such that when the cartridge is held within and / or connected to the body, the gas supply port is coupled to the cartridge.

[0081] The component may be configured such that when the cartridge is held within and / or connected to the body, the high-voltage supply port is connected to the cartridge.

[0082] The atomizer assembly can be configured to generate a spray of solvent droplets. The spray of solvent droplets can be suitable for desorbing analyte materials from the surface of a sample.

[0083] According to one aspect, an ion source is provided that includes the atomizer assembly as described above.

[0084] The ion source may also include a sampling inlet configured to collect analytes. The analytes may be generated as a result of the interaction between the spray produced by the nebulizer assembly and the sample.

[0085] The sampling inlet can be connected to analytical instruments, such as mass and / or ion mobility spectrometers.

[0086] According to another aspect, a method for generating a spray of droplets is provided, the method comprising using the aforementioned sprayer assembly to generate a spray of droplets.

[0087] According to another aspect, a method for ionizing a sample is provided, the method comprising:

[0088] Provide the sprayer components as described above; and

[0089] The spray generated by the atomizer assembly is directed toward the sample.

[0090] According to another aspect, a method for analyzing a sample is provided, the method comprising:

[0091] Provide the sprayer components as described above;

[0092] The spray generated by the atomizer assembly is directed toward the sample to produce analytes; and

[0093] Analyze the analyte.

[0094] The analyte may include analyte ions. Alternatively or additionally, the analyte may be ionized to generate analyte ions.

[0095] Analyzing the analyte may include analyzing the analyte ions to determine their mass-to-charge ratio and / or ion mobility, and / or determining the mass-to-charge ratio and / or ion mobility of ions derived from the analyte ions (e.g., by cleaving the analyte ions). Attached Figure Description

[0096] Various embodiments will now be described by way of example only and with reference to the accompanying drawings, in which:

[0097] Figure 1 A DESI (Deductive Electro-Spray Ionization) source is shown.

[0098] Figure 2 A desorption electrospray ionization (“DESI”) sprayer with a nozzle is shown;

[0099] Figure 3A This is an exploded view of a sprayer canister assembly according to various embodiments. Figure 3B This is a cross-sectional view of a sprayer canister assembly according to various embodiments. Figure 3C This is a cross-sectional view of a sprayer canister assembly according to various embodiments. Figure 3D This is a perspective view of a sprayer cartridge assembly according to various embodiments, and Figure 3E This is an internal view of a sprayer canister assembly according to various embodiments;

[0100] Figure 4A A sprayer assembly is shown, including the sprayer cartridge assembly of FIG3, which is installed for use according to various embodiments. Figure 4B This is an exploded view of the sprayer components. Figure 4C This is an exploded view of the sprayer components. Figure 4D Cross-sections of spray nozzles according to various embodiments are shown, and Figure 4E A spray nozzle according to various embodiments is shown;

[0101] Figure 5A Cross-sections of sprayer assemblies according to various embodiments are shown, and Figure 5B A cross-section of a sprayer assembly according to various embodiments is shown;

[0102] Figure 6A Sprayer assemblies according to various embodiments are shown. Figure 6B Sprayer assemblies according to various embodiments are shown. Figure 6C Cross-sections of sprayer assemblies according to various embodiments are shown. Figure 6DCross-sections of sprayer assemblies according to various embodiments are shown, and Figure 6E A cross-section of a sprayer assembly according to various embodiments is shown;

[0103] Figure 7A Cross-sections of sprayer assemblies according to various embodiments are shown, and Figure 7B A cross-section of a sprayer assembly according to various embodiments is shown;

[0104] Figure 8 A side view of the manifold body of a sprayer assembly according to various embodiments is shown;

[0105] Figure 9A A perspective rear view of a sprayer nozzle according to various embodiments is shown, and Figure 9B A perspective view of the manifold body of a sprayer assembly according to various embodiments is shown;

[0106] Figure 10 Cross-sections of sprayer assemblies according to various embodiments are shown; and

[0107] Figure 11A An end view of the sheath of a sprayer assembly according to various embodiments is shown, and Figure 11B A cross-section of the sheath of a sprayer assembly according to various embodiments is shown. Detailed Implementation

[0108] Figure 1 A typical desorption electrospray ionization (“DESI”) ion source, including a sprayer 10, is shown. Figure 1 As shown, the atomizer 10 includes a solvent capillary 12 and a gas capillary 13. The solvent capillary 12 (dispenser) is coaxially arranged within the gas capillary 13, with the solvent outlet or tip 12A of the solvent capillary 12 extending beyond the distal end of the gas capillary 13. The solvent flow 14 supplied to the solvent capillary 12 is charged by means of a high-voltage source 18 and guided toward the sample 1 with the assistance of the atomizing gas flow 15 supplied to the gas capillary 13.

[0109] The resulting spray of (primary) charged droplets 11 is capable of desorbing analyte material from the surface of sample 1, and (secondary) droplets carrying the desorbed ionized analyte can then travel via transfer capillary 20 to the atmospheric pressure interface 22 of an analytical instrument (not shown), such as a mass and / or ion mobility spectrometer. The ions can then be analyzed to determine their mass-to-charge ratio and / or ion mobility, and / or the mass-to-charge ratio and / or ion mobility of ions derived from the initial ions (e.g., by cleaving the initial ions).

[0110] The applicant has recognized that the solvent capillary 12 may be relatively fragile (e.g., containing fused silica) and therefore easily damaged.

[0111] Figure 2 An alternative desorption electrospray ionization (“DESI”) nebulizer arrangement is shown, wherein the outlet (tip) 12A of the solvent capillary 12 is located behind the nozzle (nose cone or shield) 16, and the solvent capillary 12 is positioned in line with the orifice 17 provided in the nozzle 16, such that the solvent spray 11 is guided from the solvent capillary 12 through the orifice 17 onto the sample surface.

[0112] As discussed in WO 2018 / 189534, nozzle 16 can be used to protect solvent capillary 12 during use. Orifice 17 can also provide some focusing of solvent spray 11.

[0113] As discussed above, the inventors have recognized that while nozzle 16 provides protection for solvent capillary 12 during normal use, it may be desirable to remove nozzle 16, for example, for maintenance / cleaning or to replace the nozzle with a nozzle of a different size, thereby making solvent capillary 12 susceptible to damage. Furthermore, solvent capillary 12 may be susceptible to damage during transport and installation.

[0114] The inventors have further recognized that, in an arrangement having nozzle 16, it is necessary to align the outlet 12A of the solvent capillary 12 with the orifice 17 of the nozzle 16 very precisely in order to achieve consistent performance.

[0115] In various embodiments, a sprayer assembly is provided that includes a "cannula" or sheath (i.e., a tight-fitting cap) for a (solvent) capillary. The sheath (cannula) is movable relative to the capillary between a first protected position in which the sheath covers the capillary's (solvent dispensing) outlet (tip) and a second exposed position in which the outlet (tip) is exposed (i.e., not covered by the sheath) for normal use. As the sheath moves away from the protected position toward or towards the exposed position, an elastic member, such as a compression spring, provides a restoring force to return the sheath to the protected position.

[0116] In various implementations, as will be further discussed below, the nozzle is installed to move the sheath to a second exposed position, and when the nozzle is removed, the restoring force provided by the elastic member (compression spring) returns the sheath to the first protected position.

[0117] Therefore, in various embodiments, a spring-loaded sheath is provided that can protect the solvent capillary, for example, when the nozzle is removed.

[0118] In various embodiments, as will be further discussed below, the sheath is further configured such that when the nozzle is installed, the outlet of the solvent capillary is aligned with the orifice of the nozzle.

[0119] Figure 3A Figure 3 illustrates a desorption electrospray ionization (“DESI”) sprayer assembly according to various embodiments. The assembly in Figure 3 is in the form of a cylinder 30, which includes a solvent capillary 32 surrounded by a sheath 31 and an elastic member in the form of a compression spring 33.

[0120] Figure 3A It is a breakdown view of the component. Figure 3B The image shows a sheath 31 positioned relative to the capillary 32 such that the capillary outlet (solvent discharge tip) 32A is exposed for normal use. Figure 3C The sleeve 31 is shown in a protective position in which the outlet (tip) 32A is covered by the sleeve 31 and thus protected from damage. Figure 3D It is a perspective view of the component in the exposed position, and Figure 3E An internal view of the sheath 31 is shown.

[0121] Capillary 32 can be supplied with and dispensing solvent, and therefore can be referred to as a solvent or spray capillary or dispenser. Capillary 32 can be generally tubular, with solvent supplied at one axial (solvent receiving) (inlet) end and solvent dispensed at the opposite axial end, i.e., at the outlet (or solvent dispensing tip) 32A. The capillary outlet (solvent dispensing tip) 32A can be tapered.

[0122] The capillary 32 can be formed from any suitable material such as fused silica. In this embodiment, the capillary 32 is formed from a conductive (metallic) material such as stainless steel. The inventors have found that conductive capillaries can reduce or avoid charge buildup, which could otherwise generate an undesirable electric field. Furthermore, while a metallic (e.g., stainless steel) solvent capillary 32 may be less brittle than, for example, fused silica, it can still benefit from a protective sheath, for example, due to the risk of bending.

[0123] Liquid solvent can be supplied to capillary 32 at a solvent flow rate, for example, between about 0.05 and 10 μL / min. In embodiments, the solvent flow rate can be between about 1 and 4 μL / min, such as between about 2 and 3 μL / min, or about 2 μL / min.

[0124] Solvents may include any suitable and desired solvent. For example, solvents may include organic solvents such as acetonitrile. As another example, solvents may include methanol. Other suitable solvents may include dichloromethane (optionally mixed with methanol), dichloroethane, tetrahydrofuran, ethanol, propanol, nitromethane, toluene (optionally mixed with methanol or acetonitrile), or water. Solvents may also include acids such as formic acid or acetic acid. Solvents may also include one or more additives.

[0125] The solvent droplets can be charged. Therefore, a voltage can be applied to the atomizer assembly to charge the solvent and / or solvent droplets. For example, a voltage between about 0 and 5 kV can be applied to the capillary 32 or the solvent to charge the solvent droplets. In one embodiment, a voltage between about 2 and 3 kV, such as about 2.5 kV, can be applied to the capillary 32 or the solvent. In another embodiment, a voltage between about 1 and 5 kV, such as about 1 kV, can be applied to the capillary 32 or the solvent.

[0126] In one embodiment, a voltage between about 1 and 5 kV is applied to capillary 32 or solvent, wherein the liquid solvent is supplied to capillary 32 at a flow rate between about 2 and 3 μL / min.

[0127] The sheath 31 may be typically configured as a tight-fitting (protective) cap for the capillary 32. The sheath 31 may be configured to (at least partially) coaxially surround the capillary 32. The sheath 31 may be configured such that the sheath 31 is slidable over the capillary 32 to move relative to the capillary 32 between a (first) protected position and a (second) exposed position.

[0128] In this embodiment, the (axial) length of the sheath 31 is such that the sheath can cover a large portion (most) of the capillary 32, such as at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, or at least 90% of the (axial) length of the capillary. The inventors have found that a longer sheath length can improve capillary alignment.

[0129] If able to Figure 3B and Figure 3C As seen in the image, the (axial) length of the sheath 31 can be such that when the sheath is in the (first) protected position and when the sheath is in the (second) exposed position, the solvent receiving end (inlet) of the capillary 32 is exposed (not covered by the sheath 31) to allow for easy connection to the solvent supply.

[0130] The sheath 31 can be formed from any suitable material. The sheath 31 can be formed from a relatively less brittle material, i.e., less prone to breakage or bending than the capillary, so that the sheath can protect the capillary from damage. In embodiments, the sheath is formed from metal and / or ceramic and / or plastic such as PEEK (polyetheretherketone) or PPS (polyphenylene sulfide).

[0131] The sheath 31 may be electrically insulating. For example, the sheath 31 may be formed of an electrically insulating material and / or include an electrically insulating coating. Forming an electrically insulating sheath 31 means that the sheath can (similarly) act as an insulator for a conductive (metallic) capillary.

[0132] If able to Figure 3A As seen in -E, the sheath 31 can be typically cylindrical and can be hollow, meaning it can have a typically tubular shape.

[0133] The sleeve 31 may have an axial orifice, which may be constructed and sized to accommodate the capillary 32 therein. The capillary receiving axial orifice of the sleeve 31 may be generally cylindrical and may extend centrally along the (entire) axial length of the sleeve 31. Centrally positioning the capillary receiving axial orifice of the sleeve 31 within the sleeve facilitates the alignment of the capillary 32 with respect to other components of the assembly, such as with respect to the nozzle (not shown in Figure 3).

[0134] If able to Figure 3A As seen in -E, at least a portion 31A of the axial orifice can be constructed and sized to hold the capillary 32 such that, when installed within the axial orifice, the capillary 32 is held (clamped) by the sheath 31 (and properly aligned with the other components of the assembly). Therefore, some or all of the axial orifice (of length) can have a first diameter that may be slightly larger than the diameter of the capillary 32 (e.g., with a tight gap, such as approximately 0.1 mm), such that, when installed within the axial orifice, the capillary 32 is clamped by the sheath 31 (and properly aligned with the other components of the assembly).

[0135] It is possible for the axial orifice to have the same diameter along the entire length of the sheath 31, in which case the axial orifice may have a first diameter along its entire length. However, in various embodiments, the axial orifice may have multiple different diameters along the length of the sheath 31. In this case, the axial orifice may have at least one axial segment 31A with a first diameter (such that the capillary 32 is clamped by the sheath 31), but may have one or more other segments 31B with a diameter greater than the first diameter.

[0136] For example, in various embodiments, the axial orifice includes a first axial segment 31A having a first diameter (and may be located at the end of the sheath near the capillary outlet 32A), and a second axial segment or cavity 31B having a second diameter greater than the first diameter (and may be located at the other end of the sheath).

[0137] If able to Figure 3A As seen in -C, in this implementation, the restoring force can be provided by the compression spring 33. However, it is contemplated that other elastic members may be used to provide the restoring force. The elastic member (compression spring 33) can thus be used to bias the position of the sheath 31 relative to the capillary 32 toward a protective position in which the solvent discharge tip (outlet) 32A of the capillary 32 is protected by the sheath 31.

[0138] The component can be configured such that the elastic member (compression spring 33) provides a restoring force between the capillary 32 and the sheath 31 in any suitable manner. In an embodiment, the elastic member is arranged and configured such that when the sheath 31 moves relative to the capillary 32 from a first exposed position to or toward a second protected position, the elastic member elastically deforms, for example, by compression, thereby providing a restoring force.

[0139] For example, if it is possible Figure 3A As seen in -C, the compression spring 33 can surround the capillary tube 32. A collar 32B can be provided on the capillary tube, and a shoulder 31C can be formed within the sheath 31, allowing the compression spring 33 to be compressed between the collar 32B and the shoulder 31C. (As shown in the image) Figure 3B As shown, in the exposed position, the compression spring 33 can be compressed between the collar 32B disposed on the capillary 32 and the shoulder 31C in the sheath 31. If it is possible to... Figure 3C As seen in the image, the compression spring 33 can be unloaded in the protected position.

[0140] In one embodiment, the second axial section or cavity 31B of the sheath 31 can be configured to accommodate the elastic member (compression spring 33). The end cap 34 can be configured to close the cavity 31B to retain the elastic member 33 (and the capillary 32) within the sheath 31. Placing the elastic member within the cavity 31B of the sheath protects it from damage. Furthermore, this arrangement allows the sheath 31, capillary 32, and elastic member 33 to be conveniently assembled together as a cylindrical assembly 30.

[0141] The component can be supplied with an atomizing gas flow. The component can be configured such that the atomizing gas flow interacts with (atomized) solvent released at the outlet (solvent release tip) 32A of the capillary 32 to produce a spray of solvent droplets. The atomizing gas can suitably be supplied at a pressure between about 0.1 bar and 10 bar, for example between about 0.2 bar and 5 bar, for example between about 3 bar and 5 bar, for example between about 4 bar, or between about 0.5 bar and 2 bar. The atomizing gas can be any suitable gas, such as nitrogen.

[0142] The component may also include a gas capillary that can surround the solvent capillary 32, to which atomizing gas is supplied. However, in this embodiment, the sheath 31 serves as an atomizing gas conduit for the component.

[0143] Therefore, if it is possible Figure 3D Most clearly seen in this embodiment, the sheath may include one or more gas inlets 36A configured to receive (atomized) gas streams. The one or more gas inlets 36A may include one or more gas receiving apertures disposed in the sidewalls of the sheath 31, and may be arranged and configured such that gas can enter a second axial section or cavity 31B within the sheath via the one or more gas inlets 36A. The sheath may also include one or more gas outlets 36B (e.g., one or more gas outlet holes) configured to release the received gas such that the gas interacts with (atomized) solvent released at the outlet (solvent release tip) 32A of the capillary 32 to produce a spray of solvent droplets.

[0144] If able to Figure 3E As best seen in the embodiments, the sheath 31 may include (via a second axial section or cavity 31B) one or more gas conduits 36C connecting one or more gas inlets 36A to one or more gas outlets 36B. Integrating the sheath and gas conduit functions in this way provides a simpler assembly.

[0145] One or more gas conduits 36C can be constructed as needed. For example, it is possible to... Figure 3E As seen in the diagram, in this embodiment, each gas conduit 36C may extend along at least a portion of the axial length of the sheath 31, for example, along the length of the capillary receiving axial orifice (the first axial segment 31A) and parallel thereto. Each gas conduit may be of any shape, such as typically cylindrical.

[0146] In the implementation method, such as being able to Figure 3EAs seen in the diagram, one or more axial gas conduits 36C can each be radially displaced by the same or similar radial distance from the central axis of the sheath 31, such that the central orifice and the gas conduits 36C (the first axial segment 31A) can together form a single connected cavity within the sheath 31.

[0147] In one embodiment, there are a plurality of gas conduits 36C spaced equally apart. The central orifice (the first axial segment 31A) can therefore be defined by a radially inwardly projecting portion of a sheath between the plurality of gas conduits 36C, which can be configured to centrally hold the capillary 32 within the sheath 31.

[0148] Although Figure 3E In one embodiment, the central orifice and the gas conduit 36C together form a single connected cavity within the sheath 31. However, in another embodiment, one or more or each of the central orifice and the gas conduit 36C may be separate (each may include a separate orifice (cavity) within the sheath 31). In these embodiments, one or more or each of the central orifice and the gas conduit 36C may be separated by the (inner) wall of the sheath 31.

[0149] Although Figure 3E The embodiment has three gas conduits 36C, but it is contemplated that fewer or more gas conduits may be provided. For example, the sheath 31 may include one, two, three, four, five, six, seven, eight or more gas conduits 36C.

[0150] Although Figure 3E In one embodiment, the gas conduit 36C is inside the sheath 31, but it is contemplated that the gas conduit could be configured as a channel in the outer surface of the sheath. In this case, a gas flow path can be defined between the outer surface of the sheath and the body or manifold in which the sheath is mounted.

[0151] In various embodiments, the assembly is configured as a replaceable (removable) cartridge. For example, as shown in FIG3, the assembly may be a replaceable cartridge assembly 30 including a solvent capillary 32, a sheath 31, and an elastic member 33. In these embodiments, installing the solvent capillary into the analytical instrument may include installing the cartridge assembly 30 as a single unit into the analytical instrument. This means that the solvent capillary can be protected by the sheath during installation.

[0152] Figure 4AA cartridge assembly 30, according to various embodiments, is shown mounted into the body or manifold 41 of an analytical instrument for use. The manifold (body) 41 can be formed of suitable materials such as metal and / or ceramic and / or plastics such as PEEK (polyetheretherketone) or PPS (polyphenylene sulfide). In these embodiments, the cartridge 30 can be configured as an orifice that slides into the body 41 and can be held there by attaching a nozzle 46 to the body 41. (The last sentence appears to be incomplete and possibly refers to a different embodiment.) Figure 4A As seen in the image, in the installation position, the sheath 31 can be positioned in the exposed position, such that the outlet (solvent discharge tip) 32A of the capillary 32 is not covered by the sheath 31. Therefore, in the installation position, the compression spring 33 is under compression.

[0153] If able to Figure 3A -D and Figure 4A As seen in the image, the cylinder assembly 30 may also include one or more O-ring seals 35 to provide a seal when the cylinder assembly 30 is installed in the manifold body 41.

[0154] The body 41 can be configured such that when the cylinder assembly 30 is installed in the orifice, the cylinder assembly 30 is connected to the gas inlet fitting 42 and the solvent inlet fitting 43. The manifold body 41 can be further configured such that when the cylinder assembly is installed in the orifice, a high-voltage source is connected to the solvent flow, for example, via a high-voltage port 44.

[0155] Therefore, when the cylinder assembly 30, gas inlet fitting 42, and solvent inlet fitting 43 are installed in the manifold body 41, the gas flow can be received by one or more gas inlets 36A of the sheath 31, and the solvent flow can be received by the inlet (solvent receiving end) of the solvent capillary 32. Furthermore, a high voltage can be received from the high voltage port 44 for application to the solvent.

[0156] Figure 4B and Figure 4C An exploded view of the assembly, including the cylinder assembly 30 and the manifold body 41, is shown. As can be seen in these figures, the assembly may include one or more fasteners for attaching the manifold body 41 to the analytical instrument (the rest), for example, in the form of one or more threads 411 that can be tightened to the manifold body 41.

[0157] In the implementation method, such as being able to Figure 4A As seen in -C, the capillary outlet 32A is positioned behind the removable nozzle 46. The removable nozzle 46 may have an orifice through which the capillary 32 can be arranged to guide the spray of solvent droplets through the orifice.

[0158] Nozzle 46 can take any suitable form as needed. In embodiments, the nozzle can have a generally conical or truncated conical shape. The orifice of the nozzle can generally be circular and can be positioned at the center, that is, on the central axis of the nozzle.

[0159] For example, depending on the desired spot size and the diameter of capillary 32, the size of the orifice within nozzle 46 can be selected as needed. A smaller spot size can be used to generate higher (spatial) resolution data, but provides lower sensitivity. A larger spot size can be used to achieve higher sensitivity, but has lower (spatial) resolution.

[0160] In embodiments, the diameter of the orifice can range from about 10 micrometers to about 250 micrometers. For example, the orifice diameter can range from about: (i) 50 micrometers to about 250 micrometers; (ii) 100 micrometers to about 250 micrometers; (iii) 150 micrometers to about 250 micrometers; or (iv) 175 micrometers to about 250 micrometers. Although smaller orifices generally produce sprays with a smaller initial diameter, sprays produced from smaller orifices also suffer from greater divergence. The inventors have discovered that nozzle diameters of about 200 micrometers can produce particularly reproducible sprays.

[0161] The nozzle 46 can be maintained at ground potential. Therefore, the assembly may also include means for grounding the nozzle 46, such as a grounding clamp 412. However, it is also contemplated that the nozzle 46 can be charged. For example, a voltage may be supplied to the nozzle 46 to charge (or further charge) the solvent spray as it passes through the nozzle 46 (e.g., as an alternative to or supplement to applying a voltage to the capillary 32). The voltage applied to the nozzle 46 may also be used to guide (or focus) the solvent spray as it passes through the nozzle.

[0162] The atomizer assembly can produce a fine spray of solvent droplets, for example, with a beam width of less than 50 μm at a distance of 1.5 mm from the front surface of the nozzle 46.

[0163] As described above, in various embodiments the components are configured such that installing the nozzle 46 moves the sheath 31 relative to the capillary 32 to a second exposed position, while removing the nozzle 46 moves the sheath 31 relative to the capillary 32 to a first protected position.

[0164] For example, referring to Figure 4, the assembly can be configured such that removing the nozzle 46 unloads the compression spring 33 and, in doing so, pushes the sheath 31 to extend over the outlet (solvent discharge tip) 32A of the capillary 32, thereby protecting the capillary 32 from damage. Conversely, when the nozzle 46 is installed, the nozzle 46 can push the sheath 31, causing the sheath 31 to retract to the exposed position, and the compression spring 33 is compressed. The sheath can then be held in the retracted position by connecting the nozzle 46 to the manifold body 41. This then means that when the nozzle 46 is removed, the capillary outlet (tip) 32A can be protected by the sheath 31, and when the nozzle 46 is installed, the sheath 31 can retract to allow normal use.

[0165] If able to Figure 4A As seen in the diagram, the components can be configured such that when the capillary 32 and nozzle 46 are mounted, the capillary 32 and nozzle 46 are arranged coaxially relative to each other, such that the outlet (tip) 32A of the capillary 32 is aligned (positioned in a straight line) with the orifice 46C of the nozzle 46. The inventors have discovered that spray can be particularly sensitive to the alignment (centering) of the outlet (solvent release tip) 32A of the capillary 32 with the orifice 46C of the nozzle 46, and therefore spray reproducibility can be improved by ensuring that the alignment (centering) between the nozzle orifice 46C and the capillary outlet (tip) 32A is highly reproducible.

[0166] This can be achieved in any suitable manner. In one embodiment, the component is configured with a nozzle guide that aligns the nozzle 46 coaxially with the capillary outlet (tip) 32A when the nozzle 46 is installed. This helps ensure that the orifice 46C of the nozzle 46 is centered and reproducibly positioned relative to the outlet (tip) 32A of the capillary 32.

[0167] For example, if it is possible Figure 4A and Figure 4D As best seen, the nozzle 46 may include a rear orifice 46B configured to be coaxially mounted above one end (outlet end) of the sheath 31. The orifice and the sheath end may each be generally cylindrical, but other shapes are possible. As described above, the capillary 32 may be disposed in a central axial orifice 31A within the sheath 31, and the nozzle orifice 46C may be located on the central axis of the nozzle 46 such that when the rear orifice 46B is coaxially mounted above the end of the sheath 31, the capillary outlet 32A and the nozzle orifice 46C are aligned.

[0168] Therefore, in various embodiments, mounting the nozzle 46 involves sliding the nozzle orifice 46B over the end of the sheath 31. When the nozzle orifice 46B is fully over the end of the sheath 31, further pressure applied to the nozzle 46 can retract the sheath 31 from the protected position back to the exposed position. A connector can connect the nozzle 46 to the manifold body 41 such that the sheath 31 is held in the retracted (exposed) position for use.

[0169] The nozzle connector may include a threaded connector. This arrangement allows for tool-less installation and removal of the sprayer assembly.

[0170] However, the inventors have recognized that the spray may be particularly sensitive to the distance between the nozzle orifice 46C and the solvent outlet 32A of the capillary. For example, it has been found that maintaining the solvent outlet 32A of the capillary at a distance of approximately 0.5 mm behind the nozzle orifice 46C can improve the spray performance.

[0171] The inventors have also recognized the risk of failure to fully engage the user's threaded connector. Therefore, the use of a threaded connector can increase the likelihood of variations in the distance from the nozzle orifice to the capillary outlet, which can thus be associated with a degradation in spray reproducibility.

[0172] In various implementations, the nozzle connector is a bayonet connector. Bayonet connectors may also be referred to as "1 / 4 turn" and / or "BNC" connectors. The inventors have discovered that the use of such connectors reduces the risk of variations in the distance from the nozzle orifice to the capillary outlet, thus improving spray reproducibility, for example, compared to threaded connectors.

[0173] Figure 4A -E illustrates a bayonet connector according to various embodiments. For example, it is possible to... Figure 4E As can be seen most clearly, nozzle 46 can be configured as part of a nozzle assembly including a male connector, which includes a barrel 47A and two lugs 47B that project radially inward from the rear of the barrel 47A.

[0174] If able to Figure 4C As most clearly seen, the manifold body 41 may include a complementary female connector comprising a body 47C having two recesses 47D complementary to the two lugs 47B.

[0175] A connection can be made by pushing the barrel 47A over the connector body 47C, wherein the lug 47B aligns with and passes along the groove 47D. Then, when the lug 47B extends beyond the rear surface of the connector body 47C, the barrel 47A can be rotated (e.g., 1 / 4 turn (90 degrees)) so that the lug 47B can engage the rear surface of the connector body 47C.

[0176] Figure 4D The nozzle assembly of this embodiment is shown in more detail. The nozzle assembly includes a nozzle 46 and a nozzle connector housing 47A. The nozzle can be held securely to the housing 47A, for example, between a nozzle retaining clip 46A disposed on the nozzle 46 and a spring washer 48.

[0177] Providing the nozzle and nozzle connector as separate components allows for interchangeable nozzle replacements without requiring the nozzle connector to be replaced. However, it is also envisioned that the nozzle and nozzle connector could be integrated.

[0178] If able to Figure 4A As seen in the diagram, when the nozzle 46 is connected to the manifold body 41, the nozzle 46 can be held in a position between the front of the connector body 47C and the spring washer 48. The inventors have discovered that this arrangement allows for highly reproducible capillary outlet to nozzle orifice distance.

[0179] Various alternative implementations are illustrated in Figures 5 through 7.

[0180] Although in the above embodiments, the compression spring 33 is disposed within the cavity 31B of the sheath 31, Figures 5 and 6 show embodiments in which the compression spring 33 is disposed outside the sheath 31. As can be seen in Figures 5 and 6, in these embodiments, the compression spring 33 can be compressed between the collar 32B disposed on the capillary and the (outer) end of the sheath 31.

[0181] Although in the above embodiment, the end of the retractable sheath 31 serves as a nozzle guide to guide the nozzle 46 to be coaxially aligned with the capillary 32, Figure 5A Figure 7 illustrates an embodiment in which the nozzle support 52 serves as a nozzle guide. For example, Figure 7 illustrates an embodiment in which the nozzle support 52 is configured to guide the nozzle 46 to be coaxially aligned with the capillary 32 when the nozzle 46 is installed. Figure 5A In some embodiments, the nozzle support 52 surrounding the retractable sheath 31 serves as a nozzle guide. In these embodiments, the nozzle support 52 is configured to centrally hold the capillary 32 and / or the sheath 31 to the nozzle support 52 such that when the nozzle 46 is attached to the nozzle support 52, the nozzle orifice 46C is aligned with the capillary outlet 32A.

[0182] Although in the above embodiments the nozzle 46 is connected to a bayonet connector, Figures 5 and 7 show embodiments in which the nozzle connector is a threaded connector. For example, as can be seen in Figure 5, a cap 51 with threads that are configured to attach to the nozzle support 52 can be provided.

[0183] Although in the above embodiment, the nozzle 46 can be separated from the nozzle connector, Figure 7A An embodiment in which the nozzle and connector are integrated is shown.

[0184] Although in the above embodiments, the sleeve 31 can be inserted as a cylinder into the manifold body 41 and held there by attaching the nozzle 46 to the manifold body 41, Figure 6 shows an embodiment in which the sprayer assembly 60 is removably attached to the manifold assembly 61. In this embodiment, the sprayer assembly 60 includes one or more fasteners for removably mounting the sprayer assembly 60 to the manifold assembly 61, which may be in the form of one or more external threaded connectors 67A, 67B.

[0185] In various embodiments, the manifold assembly 61 is configured with various input ports that can be connected to the injector assembly 60 when the injector assembly 60 is connected to the manifold assembly 61.

[0186] Therefore, as can be seen in FIG6, manifold assembly 61 may include an input solvent port 63A for receiving an input solvent flow, and a solvent output port 63C including a fluid seal 63B to supply solvent to the sprayer assembly 60 when the sprayer assembly 60 and the manifold assembly 61 are connected.

[0187] The manifold assembly 61 may also include an input gas port 62A for receiving an input gas flow, and a gas output port 62C including a gas seal 62B to supply gas to the sprayer assembly 60 when the sprayer assembly 60 and the manifold assembly 61 are connected.

[0188] The manifold assembly 61 may also include an input high voltage pin 64A for receiving an input high voltage, and an output high voltage pin 64B for providing a high voltage to a high voltage input terminal (not shown) of the sprayer assembly 60 when the sprayer assembly 60 and the manifold assembly 61 are connected.

[0189] Figure 6C -E shows a cross-sectional view of the sprayer assembly 60 of this embodiment. Figure 6C This is an exploded view of the sprayer assembly 60. Figure 6D The image shows a sprayer assembly 60 in which nozzle 46 has been removed and sheath 31 is positioned in a protective position. Figure 6E The sprayer assembly 60 is shown with the nozzle 46 attached and the sheath 31 in the retracted (exposed) position.

[0190] As described above, the inventors have recognized that spraying can be particularly sensitive to the distance between the nozzle orifice 46C and the solvent outlet 32A of the capillary. Therefore, in some embodiments (as described above), it may be desirable to configure the atomizer assembly such that variations in the distance from the nozzle orifice to the capillary outlet are reduced or minimized.

[0191] An alternative approach is to configure the atomizer assembly such that the distance from the nozzle orifice to the capillary outlet (in use) can be adjusted in a controllable manner. In other words, the atomizer assembly can be configured to allow the user to (controllably) adjust the distance from the nozzle orifice to the capillary outlet (in use) to achieve the desired spray performance. This means that the distance from the nozzle orifice to the capillary outlet can be precisely set to the desired value, and / or allows for relaxed manufacturing tolerances in the atomizer assembly without introducing uncontrolled variations in the distance from the nozzle orifice to the capillary outlet.

[0192] Therefore, in various embodiments, the atomizer assembly is configured such that the distance between the nozzle orifice 46C and the capillary outlet 32A is adjustable (when the atomizer assembly is in use). The distance between the nozzle orifice 46C and the capillary outlet 32A can be adjusted in a controllable manner, i.e., such that when the distance between the nozzle orifice 46C and the capillary outlet 32A is set to a specific value (by the user), the distance between the nozzle orifice 46C and the capillary outlet 32A remains at that specific value (when the atomizer assembly is used to generate a spray).

[0193] The atomizer assembly can be configured such that the distance between the nozzle orifice 46C and the capillary outlet 32A can be controllably adjusted in any suitable manner. For example, in various specific embodiments, portions of all rear surfaces of the connector body 47C (as referenced above) Figure 4C (As described) can be angled (tilted) and / or bent relative to the (vertical) front surface of the connector body 47C.

[0194] Figure 8 A side view of the manifold body 41 and connector body 47C constructed according to these embodiments is shown. Figure 8 As shown, the manifold body 41 and connector body 47C can be constructed in a manner similar to that described above. Therefore, the first (distal front) surface 47E of the connector body 47C can be parallel to the (front) surface of the manifold body 41 (these surfaces can be constructed to be perpendicular in use). The connector body 47C also has a second (rear) surface 47F configured to engage with the lug 47B of the nozzle assembly's barrel 47A when the nozzle assembly is mounted on the manifold body 41 (as described above).

[0195] However, compared to the embodiments described above, the second (rear) surface 47F of the connector body 47C may not be parallel to the first surface 47E (and the surface of the manifold body 41), for example, making the second surface 47F oblique, inclined, and / or generally not perpendicular during use. The second surface 47F may also have a curved shape, such as a cam shape. When the nozzle assembly is mounted on the connector body 47C (as described above), the lug 47B will engage the second surface 47F (due to the force from the compression spring 33), such that the distance between the nozzle orifice 46C and the capillary outlet 32A will change controllably when the barrel 47A rotates.

[0196] Various other configurations for the atomizer assembly will be possible, making the distance between the nozzle orifice 46C and the capillary outlet 32A controllably adjustable.

[0197] In this embodiment, the distance between the nozzle orifice 46C and the capillary outlet 32A may be adjustable by any suitable (relatively small) amount. For example, in this embodiment, the distance between the nozzle orifice 46C and the capillary outlet 32A may be adjusted to approximately ≤ 500 μm; ≤ 400 μm; ≤ 300 μm; ≤ 200 μm; or ≤ 100 μm.

[0198] In various specific embodiments, the second surface 47F is angled such that maximum rotation of the cylinder 47A (e.g., by about 180°) adjusts the distance between the nozzle orifice 46C and the capillary outlet 32A to about 200 μm.

[0199] Figure 9A and Figure 9B A sprayer assembly constructed according to another embodiment is shown. In these embodiments, in addition to one or more lugs 47B, the nozzle assembly may also include one or more stops (or "markers") 47G. The stops 47G may project axially inward from the rear of the cylinder 47A.

[0200] When the nozzle assembly is mounted on the manifold body 41, the stop 47G can be configured to limit the rotation of the cylinder 47A. For example, the stop 47G can be configured such that the interaction between the stop 47G and the inner wall of one or more recesses 47D (as described above) prevents the rotation of the cylinder 47A from exceeding a certain maximum rotation angle. This is possible, for example, regarding... Figure 4A -E and / or Figure 8 In any of the above embodiments, a stop 47G is provided to precisely limit the rotational movement of the cylinder 47A when the cylinder 47A is mounted on the manifold body 41.

[0201] Despite what has been shown above, especially as Figure 4A and Figure 4DAs shown, the rear orifice 46B of the nozzle 46 (and the outlet end of the sheath 31) can have a generally cylindrical shape, but the inventors have discovered that different shapes can provide improved alignment (centering) of the outlet (solvent discharge tip) 32A of the capillary 32 with the orifice 46C of the nozzle 46.

[0202] For example, such as Figure 10 As shown, the rear orifice 46B of the nozzle 46 (at least a portion thereof) may have a conical or truncated conical shape, and the outlet end of the sheath 31 may have a complementary conical or truncated conical shape. In these embodiments, the interaction between the (truncated) conical outer surface of the outlet end of the sheath 31 and the (truncated) conical inner surface of the rear orifice 46B of the nozzle 46 (due to the force and heat caused by the compression of the spring 33 when the nozzle 46 is mounted on the sheath 31) causes the outlet (solvent dispensing tip) 32A of the capillary 32 (which is held by the sheath 31) to be concentrically aligned with the orifice 46C of the nozzle 46. This arrangement has been found to significantly improve the concentric alignment of the dispenser and the nozzle orifice.

[0203] Despite as mentioned above (reference) Figures 3A to 3E The sheath 31 can be formed as a single portion having axial orifices 31A, 31B and one or more gas conduits 36C that can extend along the length of the portion of the axial orifices and are parallel to them; however, in another embodiment, the sheath 31 can be formed from multiple portions. For example, this can increase the ease of manufacturability of the sheath 31. For example, this can allow one or more of the multiple portions to be formed by injection molding.

[0204] Figure 11A An end view is shown, and Figure 11B A side cross-sectional view of the sheath 31 constructed according to these embodiments is shown. Figure 11A and Figure 11B As shown, the sheath 31 can be formed from an (outer) main sheath body 31D and a sheath insert 31E. The axial opening of the main sheath body 31D can be configured to receive and retain the sheath insert 31E. One or both of the main sheath body 31D and the sheath insert 31E can be formed by injection molding.

[0205] In these embodiments, the second axial segment or cavity 31B may be formed in the main sheath body 31D (similar to the embodiments described above), but the first axial segment 31A (which is constructed and sized to hold the capillary 32) and one or more gas conduits 36C may be formed in the sheath insert 31E.

[0206] Therefore, the sheath insert 31E may include a central axial aperture 31A (which is constructed and sized to hold the capillary 32) and one or more gas conduits 36C. Figure 9A and Figure 9BAs shown, one or more gas conduits 36C can be formed as one or more (open-side) grooves in the sheath insert 31E. It is also possible for one or more of the gas conduits 36C to be formed as orifices in the sheath insert 31E.

[0207] Other arrangements are possible.

[0208] In various embodiments, a spray of charged droplets generated by the nebulizer assembly as described above is directed toward the sample. The spray can desorb analyte material from the sample surface, and the desorbed material can then be delivered to an analytical instrument, such as a mass and / or ion mobility spectrometer, for analysis. The ions can then be analyzed to determine their mass-to-charge ratio and / or ion mobility, and / or the mass-to-charge ratio and / or ion mobility of ions derived from the initial ions (e.g., by cleaving the initial ions), etc.

[0209] While the examples above specifically relate to desorption electrospray ionization (“DESI”) systems, it should be understood that the features described herein can generally relate to a wide variety of (environmental) ion sources. For example, various techniques derived from DESI have been developed, and the techniques presented herein can be equally applied to these techniques.

[0210] Although the invention has been described with reference to preferred embodiments, those skilled in the art will understand that various changes in form and detail may be made without departing from the scope of the invention as set forth in the appended claims.

Claims

1. A cartridge for a desorption electrospray ionization ("DESI") ion source, the cartridge comprising: A capillary tube having an outlet configured to release a solvent for desorbing analyte material from a sample surface; Sheath for the capillary; as well as Elastic components; The cylinder is configured such that the sheath is movable relative to the capillary between a first position in which the sheath covers the outlet of the capillary and a second position in which the outlet of the capillary is not covered by the sheath. and The cylinder is configured such that when the sheath moves from the first position to or toward the second position, the elastic member provides a restoring force to restore the position of the sheath to or toward the first position.

2. The cylinder of claim 1, wherein the sheath includes a cavity, and the elastic member is held in the cavity within the sheath.

3. The cylinder according to claim 1, wherein the elastic member comprises a compression spring.

4. The cylinder according to claim 1, wherein: The sheath includes one or more gas inlets, one or more gas outlets, and one or more gas conduits connecting the one or more gas inlets to the one or more gas outlets; and The cylinder is configured such that gas supplied to the one or more gas inlets is released from the one or more gas outlets to atomize the solvent released from the outlet of the capillary.

5. The cylinder according to claim 4, wherein: The sheath includes an axial orifice configured to retain the capillary; and The one or more gas conduits are each arranged parallel to the axial orifice.

6. The cylinder according to claim 5, wherein the sheath is formed by a main sheath body and an insert disposed within the main sheath body, and wherein the axial orifice and the one or more gas conduits are formed in the sheath insert.

7. The cylinder of claim 3, wherein the cylinder is configured such that the compression spring can be compressed between the collar disposed on the capillary and the sheath.

8. The cylinder according to claim 1, wherein the capillary is conductive and the sheath is electrically insulating.

9. The cylinder of claim 1, further comprising one or more O-ring seals surrounding the sheath.

10. The tube of claim 1, wherein the end of the sheath is configured as a guide to guide the DESI nozzle to be coaxially aligned with the capillary.

11. A desorption electrospray ionization ("DESI") ion source, comprising the cartridge of claim 1.

12. The ion source of claim 11, comprising a sampling inlet configured to collect an analyte generated as a result of the interaction between a solvent emitted from the capillary and the sample surface.

13. A method for desorption electrospray ionization ("DESI"), the method comprising: The spray of droplets is generated using the tube of claim 1; and The droplets are sprayed toward the sample to desorb the analyte material from the surface of the sample.

14. The method of claim 13, further comprising analyzing analytes resolved from the surface of the sample.

15. The method of claim 13, further comprising mounting the cylinder in a DESI ion source assembly.

16. The method of claim 15, wherein installing the cylinder comprises moving the sheath from the first position to the second position.

17. The method of claim 13, further comprising removing the cylinder from the DESI ion source assembly.

18. The method of claim 17, wherein removing the cylinder comprises moving the sheath from the second position to the first position.

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