Sample injector for chromatography

Abstract

A sample injector for chromatography 10 where air or moisture can be prevented from getting mixed in when a sample is injected is provided with a syringe 11, a syringe drive unit 13, a turret 12 in which sample vials 4 are placed, a turret drive unit 14, and a control unit 30 that controls the syringe and turret drive units 13 and 14. The configuration includes a housing 15 having a gas introduction port 15a and a gas discharge port 15b that communicate with the inner space, where the syringe 11 sucks a sample from a sample vial 4, the sucked sample is injected into the sample vaporizing chamber 23 in a chromatograph 20, and a predetermined gas is introduced through the gas introduction port 15a, and at the same time, a predetermined gas is discharged through the gas discharge port 15b when a sample is analyzed.

Claims

1. A sample injector for chromatography, comprising: a syringe that comprises a barrel having a needle at an end thereof and a plunger that is fitted and inserted into the barrel so as to be freely slidable therein; a syringe drive unit configured to move said syringe in upward and downward directions and to push in or pull out said plunger; a turret into which a sample vial is placed, the sample vial being a vial into which a sample to be analyzed is placed; a turret drive unit configured to move said turret in a horizontal direction; a housing having an inner space, a gas introduction port and a gas discharge port, the gas introduction port and the gas discharge port communicating with the inner space, and the gas introduction port being connected to a gas supply source, a flow amount control unit including a gas flow adjusting valve, the flow amount control unit configured to control a flow of a predetermined gas introduced into the inner space by the gas introduction port, and a control unit configured to control the syringe drive unit, the turret drive unit, and the flow amount control unit, wherein said syringe is configured to suck the sample to be analyzed from the sample vial, and inject the sucked sample to be analyzed into a sample vaporizing chamber in a chromatograph from the inner space of said housing, and wherein the flow amount control unit is configured to introduce the predetermined gas from the gas introduction port so as to flow within the inner space and to exit the inner space from the gas discharge port when the sample to be analyzed is analyzed.

2. The sample injector for chromatography according to claim 1, wherein a plurality of sample vials are placed in said turret.

3. The sample injector for chromatography according to claim 1, the sample injector further comprising the sample vaporization chamber, wherein the sample vaporizing chamber including a septum through which said needle is insertable.

Description

DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic diagram showing the structure of the GC/MS according to the first embodiment;

(2) FIG. 2 is a front diagram showing the GC/MS in FIG. 1;

(3) FIG. 3 is a schematic diagram showing the structure of the GC/MS according to the second embodiment;

(4) FIGS. 4A and 4B are cross-sectional diagrams showing the 10 l syringe in FIG. 3;

(5) FIG. 5 is a schematic diagram showing the structure of a general GC/MS;

(6) FIG. 6 is a front diagram showing the GC/MS in FIG. 5; and

(7) FIG. 7 is a cross-sectional diagram showing the 10 l syringe in FIG. 5.

DETAILED DESCRIPTION OF EMBODIMENTS

(8) In the following, the embodiments of the present invention are described in reference to the drawings. Here, the present invention is not limited to the below-described embodiments, and naturally include various modifications as long as the gist of the present invention is not deviated from.

First Embodiment

(9) FIG. 1 is a schematic diagram showing the structure of the GC/MS according to the first embodiment of the present invention, and FIG. 2 is a front diagram showing the GC/MS in FIG. 1. Here, the same symbols are attached to the same components as in the above-described conventional GC/MS 101.

(10) A GC/MS 1 is provided with a gas chromatograph 20, an MS unit 50, an automatic sample injector for gas chromatography 10 provided in the upper portion of the gas chromatograph 20, a flow amount control unit 40 and a control unit 30. Here, the control unit 30 may be provided so as to be separated for each function, that is to say, the gas chromatograph 20, the automatic sample injector for gas chromatography 10, the flow amount control unit 40 and the MS unit 50 may respectively be provided with a control unit.

(11) The automatic sample injector for gas chromatography 10 is provided with a 10 l syringe 11, a syringe drive unit 13, a turret 12, a turret drive unit 14 and a housing 15 in a rectangular parallelepiped form.

(12) A gas introduction port 15a in cylindrical form is created in an upper portion of the housing 15, and at the same time, a gas discharge port 15b in cylindrical form is created in a lower portion of the housing 15. As a result, a gas that has been introduced into the inner space of the housing 15 through the gas introduction port 15a flows towards the bottom through the inner space of the housing 15 so as to be discharged to the outside of the housing 15 through the gas discharge port 15b.

(13) A predetermined gas is sealed in a gas supply source 41. In addition, one end portion of a gas introduction pipe 42 is connected to the gas supply source 41, a gas flow amount adjusting valve 43 is provided in the middle of the gas introduction pipe 42, and the other end portion of the gas introduction pipe 42 is connected to the gas introduction port 15a so that the gas supply source 41, the gas introduction pipe 42 and the gas flow amount adjusting valve 43 form a flow amount control unit 40 for supplying a predetermined gas. Here, a gas supply source 41 in which a gas of any type that is selected by the user is sealed can be attached to one end portion of the gas introduction pipe 42.

(14) The control unit 30 is provided with a CPU 31, an input unit 32 and a display unit 33 and controls the gas chromatograph 20, the MS unit 50, the automatic sample injector for gas chromatography 10 and the flow amount control unit 40.

(15) The functions processed by the CPU 31 can be described as blocks, including a flow amount control unit 31a for controlling the flow amount control unit 40, an analysis control unit 31b for receiving an ion intensity signal from a detector 55, and an injector control unit 31c for controlling the automatic sample injector for gas chromatography 10.

(16) The flow amount control unit 31a controls the gas flow amount adjusting valve 43 so that a predetermined amount of gas flows through the gas introduction pipe 42 from the gas supply source 41. For example, the user uses the input unit 32 so as to input an instruction sequential analysis start at the time of analysis so that the gas flow amount adjusting valve 43 can be controlled so as to supply a predetermined gas into the inner space of the housing 15 from the gas supply source 41 through the gas introduction pipe 42 and the gas introduction port 15a.

(17) As described above, in the GC/MS 1 according to the first embodiment, the predetermined gas with which the inner space of the housing 15 is purged can be selected so that the components that are involved at the time of injection into the sample vaporizing chamber 23 can be selected. In addition, the inner space can be continued to be purged with a gas that does not include moisture over a long period of time so that moisture that is absorbed in the end portion of the needle 11a of the syringe 11 can be removed. As a result, a more precise assay is possible by preventing an obstacle due to disturbance when a microscopic amount of moisture and air in a sample to be analyzed is analyzed even in the case where a barrier discharge ionization detector is used as the detector 55.

Second Embodiment

(18) FIG. 3 is a schematic diagram showing the structure of the GC/MS according to the second embodiment of the present invention, and FIGS. 4A and 4B are cross-sectional diagrams showing the 10 l syringe 211 in FIG. 3. Here, the same symbols are attached to the same components as in the GC/MS 1 and GC/MS 101.

(19) A GC/MS 201 is provided with a gas chromatograph 20, an MS unit 50, an automatic sample injector for gas chromatography 210 provided in the upper portion of the gas chromatograph 20, a flow amount control unit 40 and a control unit 30.

(20) The automatic sample injector for gas chromatography 210 is provided with a 10 l syringe 211, a syringe drive unit 13, a turret 12, a turret drive unit 14 and a housing 15 in a rectangular parallelepiped form, and a gas introduction port 15a in cylindrical form is created in an upper portion of the housing 15, and at the same time, a gas discharge port 15b in cylindrical form is created in a lower portion of the housing 15.

(21) The 10 l syringe 211 is provided with a barrel 11b having a needle 11a at an end, a plunger 11 that is fitted and inserted into the barrel 11b so as to be freely slidable, and a tube 212 attached to the outer periphery portion at the end of the barrel 11b.

(22) The tube 212 has an approximately cylindrical body in a bellow form that is expandable and contractible in the upward and downward directions, and a gas introduction port 212a in cylindrical form is created in an upper portion of the tube 212. As a result, a gas that has been introduced into the inner space of the tube 212 through the gas introduction port 212a flows towards the bottom through the inner space of the tube 212 so as to be discharged to the outside of the tube 212 through the opening below.

(23) In the thus-formed 10 l syringe 211, the tube 212 is in a contracted state when the upper surface of a sample vial 4 and the lower surface of the tube 212 make contact with each other, and a liquid sample can be sucked into the barrel 11b through the needle 11a, or a liquid sample can be discharged from the barrel 11b through the needle 11a (see FIG. 4B). In addition, the tube 212 is in such a state as to be expanded to a predetermined length when the lower surface of the tube 212 does not make contact with anything, and the end of the needle 11a is located inside the tube 212 (see FIG. 4A).

(24) A predetermined gas is sealed in the gas supply source 41. In addition, one end portion of a gas introduction pipe 42 is connected to the gas supply source 41, a gas flow amount adjusting valve 43 is provided in the middle of the gas introduction pipe 42, and the other end portion of the gas introduction pipe 42 is connected to the gas introduction port 212a through the gas introduction port 15a so that the gas supply source 41, the gas introduction pipe 42 and the gas flow amount adjusting valve 43 form a flow amount control unit 40 for supplying a predetermined gas.

(25) As described above, in the GC/MS 201 according to the second embodiment, the predetermined gas with which the inner space of the tube 212 is purged can be selected so that the components that are involved at the time of injection into the sample vaporizing chamber 23 can be selected. In addition, the inner space can be continued to be purged with a gas that does not include moisture over a long period of time so that moisture that is absorbed in the end portion of the needle 11a of the syringe 11 can be removed. As a result, a more precise assay is possible by preventing an obstacle due to disturbance when a microscopic amount of moisture and air in a sample to be analyzed is analyzed even in the case where a barrier discharge ionization detector is used as the detector 55.

Other Embodiments

(26) Though the flow amount control unit 31a has such a structure that the gas flow amount adjusting valve 43 can be controlled when the user uses the input unit 32 so as to input an instruction sequential analysis start in the above-described GC/MS, an alternative structure may be possible where the user uses the input unit 32 so as to input open or close according to an appropriate timing in order to control the gas flow amount adjusting valve 43.

INDUSTRIAL APPLICABILITY

(27) The present invention can be applied to a chromatograph mass spectrometer.

EXPLANATION OF SYMBOLS

(28) 4 vial 10 sample injector for gas chromatography 11 syringe 11a needle 11b barrel 11c plunger 12 turret 13 syringe drive unit 14 turret drive unit 15 housing 15a gas introduction port 15b gas discharge port 23 sample vaporizing chamber 30 control unit