WO2019049272A1

WO2019049272A1 - Ion source and ion analysis device

Info

Publication number: WO2019049272A1
Application number: PCT/JP2017/032300
Authority: WO
Inventors: 智仁中野
Original assignee: 株式会社島津製作所
Priority date: 2017-09-07
Filing date: 2017-09-07
Publication date: 2019-03-14
Also published as: JP6747602B2; JPWO2019049272A1

Abstract

In the present invention, a screw receiving part (41) that an adjustment screw (42) is screwed into and a shaft support (46) are provided on the outside of an ionization chamber (21) wall surface (21a) at positions having an ionization probe (22) therebetween. One end of an arm (45) that includes a flat bar part is pivotally supported by the shaft support (46), and the other end of the arm (45) is connected to a connection part (48) that is attached to the adjustment screw (42). Additionally, a central part of the arm (45) is connected to a protruding part (47) provided in a probe body (220). At the locations of the connections, protruding parts (48a, 47) are capable of moving within elongated holes (45a, 45b). If the arm (45) rotates around a shaft body (46a) as a result of the operation of the adjustment screw (42), the probe body (220) is moved smoothly in the axial direction via the protruding part (47) and long hole (45b). As a result, it is possible to accurately adjust the position of the ionization probe (22) in the axial direction.

Description

Ion source and ion analyzer

The present invention relates to an ion source for ionizing components in a liquid sample, and an ion analyzer such as a mass spectrometer or an ion mobility analyzer equipped with the ion source, more specifically, an electrospray ionization (ESI) method, An ion source having an ionization probe for spraying a liquid sample to perform ionization by an atmospheric pressure chemical ionization (APCI) method or an ionization method such as an atmospheric pressure photoionization (APPI) method, and an ion analysis equipped with the ion source It relates to the device.

In a liquid chromatograph mass spectrometer (hereinafter appropriately referred to as “LC-MS” as appropriate) in which a liquid chromatograph and a mass spectrometer are combined, an eluate containing various components separated in the time direction with the liquid chromatograph column is used. After being introduced into a mass spectrometer and ionized by the ion source of the mass spectrometer, ions from the sample component are separated and detected according to the mass-to-charge ratio m / z by a mass separator such as a quadrupole mass filter. In the mass spectrometer used for LC-MS, atmospheric pressure ionization methods such as ESI method, APCI method, and APPI method are used to ionize the components in the liquid sample.

In recent years, particularly in the fields of biochemistry, medicine, drug development, etc., there are cases where the amount of sample to be analyzed is very small or the value of the sample is often valuable or expensive. Analysis is required. In order to meet such demands, liquid chromatographs employ a method of reducing the flow rate of the mobile phase supplied to the column while using a small diameter column. Corresponding to this, in the ion source of the mass spectrometer, there is adopted, for example, a method called nano-ESI or micro-ESI which efficiently ionizes the components in the eluate while suppressing the flow rate of the eluate introduced into the ionization probe. It is done.

As disclosed in Patent Document 1, in LC-MS, ions derived from sample components generated from a spray flow from an ionization probe are subjected to gas pressure from an ionization chamber which is a substantially atmospheric pressure atmosphere through a narrow diameter desolvation tube. It is sent to the next lower intermediate vacuum chamber. Therefore, in order to improve the analysis sensitivity, it is necessary to efficiently feed the ions generated in the ionization chamber into the desolvation tube. When the ionization probe is moved in its axial direction, the distance between the capillary end of the ionization probe and the ion inlet of the desolvation tube and the angle between the two axes change, and transport of ions through the desolvation tube Efficiency changes. Therefore, there is conventionally known an ion source capable of adjusting the axial position of the ionization probe so as to adjust the analysis sensitivity.

FIG. 4 is a schematic cross-sectional view of an example of a conventional atmospheric pressure ion source capable of axial position adjustment of the ionization probe.
The ionization probe 22 includes a probe main body 220 having a nebulize gas flow path inside, and a capillary 221 with a small diameter through which a liquid sample supplied from the outside flows. The probe body 220 has a substantially cylindrical shape and has a substantially conical nozzle 220a at its tip, and the end 221a of the capillary 221 slightly protrudes from the tip of the nozzle 220a. The probe main body 220 is held by a substantially annular probe holder 23 mounted on the wall surface 21 a of the ionization chamber 21 in a substantially atmospheric pressure atmosphere. The inner circumferential surface of the probe holding portion 23 has appropriate slipperiness, and by pushing the probe main body 220 from the outside of the ionization chamber 21 to the inner side of the ionization chamber 21 or pulling it out in reverse, The axial position can be adjusted.

An arm 43 projecting in a direction perpendicular to the axial direction of the capillary 221 is fixed to the probe main body 220 in order to push in and pull out the probe main body 220, and an adjustment screw 42 is axially mounted on an end of the arm 43. It is supported. A screw receiving portion 41 having a screw hole formed on the inner peripheral side is attached to the outside of the wall surface 21 a of the ionization chamber 21, and a screw thread portion of the adjusting screw 42 is screwed into the screw hole of the screw receiving portion 41. . The screwing direction of the adjusting screw 42 coincides with the axial direction of the probe main body 220. When the head portion of the adjusting screw 42 is rotated and the screw thread portion is screwed into the screw hole of the screw receiving portion 41, the arm 43 fixed at one end to the adjusting screw 42 moves in a substantially axial direction accordingly . Thereby, the probe main body 220 fixed to the other end of the arm 43 is pushed into the ionization chamber 21 as shown by the arrow B in FIG.

U.S. Pat. No. 9,254,497

However, in the ion source configured as described above, when the adjustment screw 42 is screwed in, a force in the direction of rotating the arm 43 and the probe main body 220 acts as shown by arrow A in FIG. 4. Therefore, the probe main body 220 does not move straight along the axial direction, but moves in the axial direction as a whole while swinging about the axis. As a result, not only does it interfere with the accurate position adjustment of the ionization probe 22 but also a large load is applied to the probe holder 23 to cause deterioration due to wear and the like. In order to smoothly move the probe main body 220 in the axial direction while restricting the movement of the probe main body 220 in a direction other than the axial direction, it is desirable to increase the axial length of the probe holding portion 23. However, the axial length of the probe holder 23 is restricted by the axial length of the probe body 220. In the ionization probe for low flow rate ESI called nano ESI or micro ESI described above, the reduction in sensitivity due to the diffusion of the sample component derived from the length of the pipe becomes a problem in particular. Therefore, in such a low flow rate ESI, the extension of the capillary 221 accompanied by the lengthening of the length of the probe main body 220 in the axial direction is not particularly preferable in view of the decrease in sensitivity.

Further, in the ion source configured as described above, in order to reduce the force other than the axial direction acting on the arm 45 and the probe main body 220 when the adjusting screw 42 is screwed, the length of the arm 43 is shortened. The screw receiver 41 may be provided at a position close to the probe main body 220. However, when the adjusting screw 42 and the screw receiving portion 41 are close to the probe main body 220, replacement of the capillary 221, the inlet end of the capillary 221 and the outlet end of the column of the liquid chromatograph (or the end of the pipe connected thereto) It becomes difficult to do work such as connection with).

In particular, in the low flow rate ESI, the pipe length from the column outlet end to the ionization probe is as short as possible, and since it is common to arrange the column and the capillary of the ionization probe coaxially, The space between the column (and the column oven in which the column is placed) and the ionization probe body is very small. When the adjusting screw 42 is disposed in such a narrow space, the operator needs to operate the adjusting screw 42 in the narrow space, and the workability becomes extremely poor. Therefore, the adjustment screw 42 and the screw receiving portion 41 must be disposed at a position apart from the probe main body 220 to some extent, and the force other than the axial direction acting on the arm 45 and the probe main body 220 is also reduced at that point. It is difficult.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to adjust the axial position of the ionization probe by operating at a certain distance from the installation position of the ionization probe. It is an object of the present invention to provide an ion source capable of performing the process smoothly and accurately and an ion analyzer using the ion source.

The present invention, which was made to solve the above problems, has an ionization chamber and a nozzle for spraying a liquid sample into the ionization chamber, and has an opening formed in the wall surface of the ionization chamber movably in the axial direction. An ion source comprising: an ionization probe held in a inserted state; and ionizing a component contained in a liquid sample sprayed into the ionization chamber by the ionization probe,
a) an adjusting operation unit which is disposed outside the ionization chamber and at a position away from the ionization probe and is movable in the same direction as the axial direction of the ionization probe according to an operation from the outside;
b) An arm support portion disposed outside the ionization chamber at a position opposite to the adjustment operation portion with the ionization probe interposed therebetween;
c) a rod-like portion whose one end is pivotally supported by the arm shaft supporting portion, and the other end is attached rotatably and movably in a predetermined range in the extending direction of the rod-like portion in the adjustment operation portion; An arm portion attached to the ionization probe so as to be movable and rotatable in a predetermined range in the extending direction at an intermediate position of the rod-like portion;
It is characterized by having.

The ion source according to the present invention typically performs ionization by the ESI method, the APCI method, or the APPI method. For example, in the case of an ion source based on the ESI method, an appropriate component corresponding to the type of the ionization method may be provided, such as providing an electric field forming unit for charging the liquid sample immediately before being sprayed from the ionization probe. It is natural.

In the ion source according to the present invention, when performing axial position adjustment of the ionization probe, for example, the operator manually operates the adjusting operation unit to move the adjusting operation unit by an appropriate amount. One end of the rod portion of the arm portion is attached to the adjustment operation portion, and the other end is pivotally supported by the arm support portion. Therefore, when the adjustment operation portion moves linearly, the rod portion is supported Rotate around the position where it is Since the adjusting operation unit moves linearly, the distance between the attachment position of the rod portion (force point to which force is applied) in the adjusting operation unit and the fulcrum changes with the rotation of the arm unit. Since the position is movable in a predetermined range in the extension direction of the rod-like portion, the change in the distance is absorbed thereby. On the other hand, as the arm portion rotates about the fulcrum, a force acts to rotate the ionization probe via the attachment position (working point) between the rod portion and the ionization probe. However, since the attachment position of the rod portion and the ionization probe is also movable in a predetermined range in the extension direction of the rod portion, the attachment position also moves with the rotation of the arm portion, whereby the ionization probe It moves linearly in the axial direction.

Thus, in the ion source according to the present invention, the ionization probe can be smoothly moved in the axial direction. Further, in the ion source according to the present invention, the amount of movement of the ionization probe is smaller than the amount of movement (adjustment amount) of the adjustment operation unit, so it is easy to adjust the fine position of the ionization probe.

As described above, although the attachment position of the rod portion and the ionization probe moves in the extension direction of the rod portion when the arm portion rotates, the action direction of the force on the ionization probe is not the axial direction. However, the direction of the force acting on the ionization probe can be made close to the axial direction by setting the fulcrum supporting the rod-like portion as far as possible from the point of action of the ionization probe. Thereby, the oscillation of the ionization probe can be effectively suppressed.

In the ion source according to the present invention, the adjusting operation unit includes a screw receiving portion whose position is fixed to a wall surface of the ionization chamber, and an adjusting screw having a screw portion screwed into the screw receiving portion. It can be configured to include.

In this configuration, the position of the ionization probe in the axial direction is adjusted by, for example, manually turning the head of the adjustment screw by manual operation and adjusting the screwing depth of the screw portion into the screw receiving portion. That is, the axial position of the ionization probe can be finely adjusted by the number of times the head of the adjustment screw is turned and the angle thereof. Thus, for example, in a mass spectrometer equipped with the ion source according to the present invention, the axial position of the ionization probe can be easily adjusted so as to obtain high analysis sensitivity.

Further, in the ion source according to the present invention, preferably, the arm portion is a U-shaped top view member including two linear rod portions arranged in parallel with the ionization probe interposed therebetween. .

According to this configuration, when the arm portion rotates, the ionization probe receives a force in the substantially axial direction from the rod-shaped portions on both sides thereof via the action points. Therefore, even if the probe holding portion that holds the ionization probe in the opening formed on the wall surface of the ionization chamber is relatively short in the axial direction, the ionization probe smoothly moves in the axial direction, and the accurate position can be obtained. It can be adjusted.

An ion analyzer according to the present invention is characterized by including the ion source according to the present invention.

The ion analysis apparatus according to the present invention is usually a mass spectrometer that separates and detects ions generated by the ion source or ions derived from the ions according to the mass-to-charge ratio, or ions generated by the ion source Alternatively, the present invention is any of the ion mobility analyzer which separates and detects ions derived from the ions according to the ion mobility. Of course, it is also possible to use an ion mobility-mass spectrometer which separates ions according to ion mobility and then according to mass-to-charge ratio.

In the ion analyzer according to the present invention, preferably, an eluate containing the component separated by the liquid chromatograph column is introduced into the ion source of the ion analyzer, and the outlet end of the column Preferably, the sample flow path in the ionization probe is directly connected to the inlet end of the capillary.
Here, with the configuration in which “the outlet end of the column and the inlet end of the capillary that is the sample flow channel in the ionization probe are directly connected”, the two are connected via a very short relay pipe. Includes substantially directly connected configurations. Further, "very short" is a state in which the column and the capillary are connected such that the column oven in which the column is accommodated and the ionization probe are disposed completely or almost completely.

When the outlet end of the liquid chromatograph column and the inlet end of the capillary are substantially directly connected, the column oven in which the column is housed is placed in the vicinity of the ionization probe. On the other hand, in the ion source according to the present invention, the axial position of the ionization probe can be adjusted by the operation of the adjustment operation part provided at a position distant from the ionization probe. It is not necessary to arrange the adjustment operating unit in the space between the ionization probe and the column oven. This allows the column oven to be placed in close proximity to the ionization probe. Further, in the ion analyzer according to the present invention, diffusion of the components separated in the column is suppressed by substantially directly connecting the outlet end of the column and the inlet end of the capillary in this manner, and high sensitivity is achieved. Analysis of the As such, the ion source according to the present invention is particularly suitable for low flow ESI called nano ESI or micro ESI.

According to the ion source according to the present invention, the axial position of the ionization probe can be adjusted smoothly and accurately by the operation at a certain distance from the installation position of the ionization probe. In addition, since it is difficult to cause oscillation of the ionization probe at the time of axial position adjustment of the ionization probe, it is difficult for an excessive force to be applied to the probe holder holding the ionization probe on the wall surface of the ionization chamber. Damage can be reduced. In addition, the high accuracy of the position adjustment of the ionization probe enables the ion analyzer equipped with the ion source according to the present invention to realize high analysis sensitivity.

The top view of the principal part of the ionization probe which is one example of the present invention. The partial cross section schematic block diagram of the principal part of the ionization probe of a present Example. The schematic block diagram of LC-MS using the ionization probe of a present Example. BRIEF DESCRIPTION OF THE DRAWINGS The schematic sectional drawing of the conventional general ionization probe.

Hereinafter, an ion source according to an embodiment of the present invention and LC-MS using the same will be described with reference to the attached drawings.
FIG. 1 is a plan view of the main part of the ion source according to the present embodiment, and FIG. 2 is a schematic cross-sectional view of the ion source according to the present embodiment. FIG. 3 is a schematic configuration view of one embodiment of LC-MS using the ion source of this embodiment. For convenience of explanation, in FIG. 3, X-axis, Y-axis, and Z-axis orthogonal to each other are defined as illustrated. In this LC-MS, the Z-axis direction is the lateral direction, the X-axis direction is the height direction, and the Y-axis is the depth direction.

First, the configuration and schematic analysis operation of the LC-MS of the present embodiment will be described with reference to FIG.
This LC-MS is roughly divided into a liquid chromatograph 1 and a mass spectrometer 2. The liquid chromatograph 1 includes a mobile phase container 10, a liquid feed pump 11, an injector 12, a column 14, and a column oven 13.
The column oven 13 includes an oven chamber (not shown) in which a heater and a cooler are disposed and the periphery is covered with a heat insulating material, and the column 14 is accommodated in the oven chamber. The column oven 13 is disposed such that the outlet end 14a of the column 14 disposed therein is aligned with a relay pipe 223 of the ionization probe 22 described later.

The mass spectrometer 2 includes an ion source 20 and an analysis unit 200. The ion source 20 and the analysis unit 200 are housed in a horizontally long casing (not shown) together with a vacuum pump (not shown) and the like. As shown in FIG. 3, this mass spectrometer 2 is a triple quadrupole mass spectrometer. The ion source 20 is an ESI ion source, and includes an ionization probe 22 that sprays charged droplets into the ionization chamber 21 maintained at a substantially atmospheric pressure atmosphere. The ionization probe 22 has a capillary 221 through which a low flow rate liquid sample flows, and the inlet end of the capillary 221 is connected to the relay pipe 223 by the joint 222, and the inlet end of the relay pipe 223 is substantially Horizontally taken out of the case. The inlet end of the relay pipe 223 is inserted into the column oven 13 of the liquid chromatograph 1 and connected to the outlet end 14 a of the column 14. The relay pipe 223 is made of resin such as PEEK (polyether ether ketone) resin, for example, and since the metal capillary 221 is not exposed to the outside of the ionization probe 22, high safety can be ensured.

The analysis unit 200 is entirely housed in the vacuum chamber 201. The inside of the vacuum chamber 201 is divided into a first intermediate vacuum chamber 202, a second intermediate vacuum chamber 203, and a high vacuum chamber 204 from the side close to the ionization chamber 21. Each of the chambers 202 to 204 is evacuated by a vacuum pump to form a differential exhaust system in which the degree of vacuum gradually increases from the ionization chamber 21 toward the high vacuum chamber 204.

The ionization chamber 21 and the first intermediate vacuum chamber 202 communicate with each other through a narrow diameter solvent removal pipe 24, and a plurality of electrode plates disposed in the first intermediate vacuum chamber 202 so as to surround the ion optical axis C. An ion guide 205 is provided. The first intermediate vacuum chamber 202 and the second intermediate vacuum chamber 203 communicate with each other through the small hole at the top of the skimmer 206, and the second intermediate vacuum chamber 203 is composed of a plurality of rod electrodes surrounding the ion light axis C. An ion guide 207 is installed. In the high vacuum chamber 204, the front quadrupole mass filter 208 and the rear quadrupole mass filter 211 are disposed with the collision cell 209 in which the ion guide 210 is disposed, and the ion detector 212 is further disposed. It is provided.

In the liquid chromatograph 1, the liquid feed pump 11 sucks and feeds the mobile phase stored in the mobile phase container 10. When a certain amount of sample liquid is injected from the injector 12 into the mobile phase, the sample liquid is introduced into the column 14 following the flow of the mobile phase. Then, while the sample solution passes through the column 14 temperature-controlled by the column oven 13, various components contained in the sample solution are separated in the time direction and reach the outlet end 14 a of the column 14. When the eluate containing the components separated in the column 14 is introduced into the capillary 221 through the relay pipe 223 of the ionization probe 22, charged droplets derived from the eluate are sprayed from the end of the capillary 221 into the ionization chamber 21. Be done. The charged droplets collide with the atmosphere to be miniaturized, and the sample component becomes gas ions in the process of evaporation of the solvent. The generated ions are absorbed into the desolvation pipe 24 on the gas flow formed by the differential pressure at both ends of the desolvation pipe 24 and introduced into the first intermediate vacuum chamber 202.

As described above, the ions derived from the sample component introduced into the first intermediate vacuum chamber 202 are converged by the ion guide 205, and are sent to the second intermediate vacuum chamber 203 through the small holes of the skimmer 206. The ions are focused by the ion guide 207, sent to the high vacuum chamber 204, and introduced into the front quadrupole mass filter 208. Among the ions derived from the sample components introduced, only ions having a specific mass-to-charge ratio corresponding to the voltage applied to the front quadrupole mass filter 208 pass through the front quadrupole mass filter 208 and the precursor ion The collision cell 209 is entered. In the collision cell 209, a CID (collision induced dissociation) gas is continuously or intermittently introduced, and the precursor ions are dissociated in contact with the CID gas to generate various product ions. This product ion is introduced into the second-stage quadrupole mass filter 211, and only the product ion having a specific mass-to-charge ratio corresponding to the voltage applied to the second-stage quadrupole mass filter 211 is the second-stage quadrupole mass filter 211. It passes through to reach the ion detector 212. The ion detector 212 generates a detection signal according to the amount of ions reached.

In order to achieve high analytical sensitivity in the above LC-MS, the axial direction (Z-axis direction) of the ionization probe 22 according to the flow rate of the mobile phase (liquid transfer rate) in the liquid chromatograph 1, the type of mobile phase, etc. It is desirable to adjust the position of In order to perform such position adjustment, the ion source 20 of the present embodiment is provided with a position adjusting mechanism 40 having the following characteristic configuration. The position adjusting mechanism 40 will be described in detail with reference to FIGS. 1 and 2.

FIG. 1 is a plan view of the state in which the ionization probe 22 mounted in the ionization chamber 21 is viewed from the left side. Moreover, FIG. 2 is a partially sectioned schematic configuration diagram showing only some of the components in a cross section (but not in the same plane) for easy understanding. In FIGS. 1 and 2, the same components as the components in the conventional ion source shown in FIG. 4 are given the same reference numerals to clarify the correspondence.

In the ion source 20 of this embodiment, the probe main body 220 of the ionization probe 22 has a substantially cylindrical shape as in the prior art, and is held in a state of being inserted into the central opening of the substantially annular probe holder 23. A screw receiving portion 41 having a screw hole formed on the inner peripheral side thereof is fixed to a position outside the wall surface 21 a of the ionization chamber 21 and separated by a predetermined distance from the ionization probe 22. Then, a shaft 46 is fixed to the outside of the wall surface 21 a of the ionization chamber 21 on the opposite side of the screw receiving portion 41 on both sides of the ionization probe 22 with the ionization probe 22 on the X axis. There is. A shaft 46 a extending in the Y-axis direction is attached to the shaft base 46.

The shaft 46a rotatably supports the ends of the pair of flat rod portions of the substantially U-shaped arm 45 including a pair of flat rod portions extending in parallel and linearly. The distance between the pair of flat rod portions of the arm 45 is larger than the outer diameter of the probe main body 220 of the ionization probe 22, and the length of the flat rod portion is about the same as the distance between the screw receiving portion 41 and the shaft base 46 It is slightly longer than that. A connecting portion 48 having a substantially cylindrical protrusion 48 a is attached to both sides of the adjusting screw 42 screwed into the screw hole of the screw receiving portion 41. The connecting portion 48 is attached to the adjusting screw 42 so as not to interlock with the rotation of the adjusting screw 42 but interlocked to advancing and retracting in the Y-axis direction. An elongated hole 45a elongated in the extending direction of the flat rod portion is formed at the end of the pair of flat rod portions of the arm 45 on the opposite side to the support position by the shaft 46a. The projection 48a is loosely fitted in the long hole 45a.

Further, the probe main body 220 is also provided with a pair of substantially cylindrical protrusions 47 extending in the Y-axis direction, and the pair of protrusions 47 extend in the extending direction between the flat portions of the pair of flat bar portions of the arm 45. It is loosely fitted in the formed long hole 45a. That is, the arm 45 is rotatably supported by the shaft 46a, is connected to the adjustment screw 42 at a position opposite to the rotation axis, and is moved in the Y-axis direction at the middle of the pair of flat bar portions. Is coupled to the probe body 220. The position adjustment mechanism 40 centering on the arm 45 utilizes the principle of lever, and the support position by the shaft 46a is a fulcrum, the connection position by the protrusion 48a is a force point to which external force is applied, and the protrusion It can be understood that the connection position by the part 47 is the action point.

When the operator turns the head of the adjusting screw 42 and screws the adjusting screw 42 into the screw receiving portion 41, the connecting portion 48 moves in the Z-axis direction accordingly. Then, a force that causes the arm 45 to rotate in the direction indicated by the arrow a in FIG. 2 is applied via the projection 48 a, that is, from the point of force. Thus, as the arm 45 rotates and approaches the X-axis direction, the projection 48a moves in the longitudinal direction in the long hole 45a. Thus, the arm 45 can be smoothly rotated while linearly moving the adjusting screw 42 in the Z-axis direction.

When the arm 45 rotates in this manner, a force is applied to the probe main body 220 through the long hole 45 b and the projection 47. Assuming that the projection 47 is connected to the arm 45 through a round hole without play, the rotation of the arm 45 is transmitted to the probe main body 220 as it is, so the direction of the force applied to the probe main body 220 does not become axial. On the other hand, in the position adjusting mechanism 40, since the projection 47 is connected to the arm 45 via the long hole 45b, as the arm 45 rotates, the projection 47 is in the long hole 45b in the longitudinal direction Move to As a result, a force (in the Z-axis direction) is applied substantially in the axial direction (in the Z-axis direction) to the probe main body 220 from the projection 47, that is, the point of action.

As described above, the axial position of the ionization probe 22 can be easily adjusted by the operation of the adjustment screw 42 by the operator. In this position adjustment mechanism 40, since the shaft base 46, the adjustment screw 42 and the screw receiving portion 41 are disposed on both sides of the ionization probe 22, ionization is performed compared to the amount of movement of the adjustment screw 42 in the Z axis direction. The amount of movement of the probe 22 in the Z-axis direction is small. Therefore, fine axial position adjustment of the ionization probe 22 can be easily performed.

As the distance between the fulcrum and the point of application is reduced, the direction of the force applied to the point of application is inclined with respect to the Z axis direction. Therefore, it is desirable that the distance between the fulcrum and the point of action be greater, and it is better to separate the spindle 46 from the probe main body 220 as much as possible. Further, if the distance between the adjustment screw 42 and the screw receiver 41 and the ionization probe 22 is long enough that the adjustment screw 42 and the screw receiver 41 do not hinder the maintenance of the ionization probe 22 and the installation of the column oven 13. Good.

Further, the above-described embodiment is only an example of the present invention, and it is natural that the present invention is included in the claims of the present invention even if appropriately changed, modified or added within the scope of the present invention.

For example, although the ion source in the above embodiment performs ionization by the ESI method, it may perform ionization by the APCI method or the APPI method. In the ion source by the APCI method, a needle electrode for generating a corona discharge is disposed in front of the spray flow of the sample droplet, and a buffer gas introduced into the ionization chamber by the corona discharge generated by a high voltage applied to the needle electrode. Or ionize the solvent gas vaporized from the liquid sample. Then, the gas component and the vaporized sample component may be chemically reacted to ionize the sample component. Further, in the ion source according to the APPI method, the spray flow of the sample droplet may be irradiated with light (ultraviolet light) of a predetermined wavelength, and the vaporized sample component may be ionized by the light energy.

Further, although the embodiment shown in FIG. 3 is an example in which the ion source according to the present invention is applied to LC-MS, ions derived from sample components generated by the ESI method or the like are separated and detected according to ion mobility. The ion source according to the present invention is applied to an ion mobility analyzer and an ion mobility-mass spectrometer which further separates generated ions derived from sample components according to ion mobility according to mass-to-charge ratio. It is also clear that it is applicable.

DESCRIPTION OF SYMBOLS 1 ... Liquid chromatograph 10 ... Mobile phase container 11 ... Liquid feeding pump 12 ... Injector 13 ... Column oven 14 ... Column 14a ... Exit side end part 15 ... Joint 2 ... Mass spectrometer 20 ... Ion source 200 ... Analysis part 201 ... Vacuum Chamber 202 ... first intermediate vacuum chamber 203 ... second intermediate vacuum chamber 204 ...

high vacuum chamber

205, 207, 210 ... ion guide 206 ... skimmer 208 ... first stage quadrupole mass filter 209 ... collision cell 211 ... second stage quadrupole mass Filter 212: Ion detector 21: Ionization chamber 21a: Wall surface 22: Ionization probe 220: Probe main body 220a: Nozzle 221: Capillary 222: Joint 222: Relay pipe 23: Probe holder 24: Desolvation pipe 40: Position adjustment mechanism 45 ...

arm

45a, 45b ... elongated hole 46 ... shaft base 46a ... shaft body 47, 8a ... protrusions 48 ... connecting part

Claims

And an ionization probe having a ionization chamber, and a nozzle for spraying a liquid sample into the ionization chamber, and held in a state of being inserted into an opening formed in a wall surface of the ionization chamber so as to be movable in the axial direction. An ion source for ionizing components contained in a liquid sample sprayed into the ionization chamber by the ionization probe;
a) an adjusting operation unit which is disposed outside the ionization chamber and at a position away from the ionization probe and is movable in the same direction as the axial direction of the ionization probe according to an operation from the outside;
b) An arm support portion disposed outside the ionization chamber at a position opposite to the adjustment operation portion with the ionization probe interposed therebetween;
c) a rod-like portion whose one end is pivotally supported by the arm shaft supporting portion, and the other end is attached rotatably and movably in a predetermined range in the extending direction of the rod-like portion in the adjustment operation portion; An arm portion attached to the ionization probe so as to be movable and rotatable in a predetermined range in the extending direction at an intermediate position of the rod-like portion;
An ion source comprising:
The ion source according to claim 1, wherein
The ion source characterized in that the adjusting operation part includes a screw receiving part whose position is fixed to a wall surface of the ionization chamber, and an adjusting screw having a screw part screwed into the screw receiving part. .
The ion source according to claim 1, wherein
3. The ion source according to claim 1, wherein the arm unit is a U-shaped member in top view including two straight rod-like portions arranged in parallel with the ionization probe interposed therebetween.
An ion analyzer comprising the ion source according to claim 1.
The ion analyzer according to claim 4, wherein
An eluate containing components separated by a liquid chromatograph column is introduced into an ion source of the ion analyzer, and an outlet end of the column and an inlet side of a capillary which is a sample flow path of the ionization probe. An ion analyzer characterized in that it is directly connected to an end.
The ion analyzer according to claim 5, wherein
An ion analyzer characterized in that ions generated by the ion source or ions derived from the ions are separated and detected according to mass-to-charge ratio.
The ion analyzer according to claim 5, wherein
An ion analyzer characterized by separating and detecting an ion generated by the ion source or an ion derived from the ion according to ion mobility.