JP3404205B2 - Liquid chromatograph / mass spectrometer - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid chromatograph (LC) in which a column eluate is introduced into a mass spectrometer (MS) through an interface section, and the liquid chromatograph is used as a liquid chromatograph. The present invention relates to a liquid chromatograph / mass spectrometer (LC / MS) for performing qualitative or quantitative analysis of separated components using a mass spectrometer. [0002] In a liquid chromatograph / mass spectrometer, a standard sample needs to be injected into the mass spectrometer in order to tune the mass spectrometer. Tuning is
It is to adjust the resolution of the analysis section, adjust the sensitivity, calibrate the mass number, and adjust the optimum temperature of the sheath heater of the probe for the heated capillary or APCI (atmospheric pressure chemical ionization). As a standard sample injection method for tuning a mass spectrometer, it is conceivable to use a liquid chromatography pump for liquid injection and to inject the sample into the mass spectrometer through a column. Since the analysis sample may be contaminated by the standard sample, it is not generally adopted. Therefore, a standard sample is usually collected in a syringe or the like, set in a separately prepared syringe pump, and injected into the mass spectrometer. [0004] When a standard sample for tuning is injected by using a syringe, the standard sample is sucked, set in a syringe pump, and piping from the syringe pump to the interface of the mass spectrometer. Must be performed each time tuning is performed, which is complicated and has poor operability. Since the connection of the liquid chromatograph to the interface of the mass spectrometer and the connection of the tubing from the syringe pump must be changed, it is impossible to perform re-tuning during a routine analysis for performing a normal analysis. [0005] Since the separately connected syringe pump is not connected to the control unit of the mass spectrometer, it is not possible to set the injection speed of the standard sample or the like from the mass spectrometer side and to perform auto tuning. In addition, since the amount of the standard sample that can be injected is limited to the amount collected by the syringe, the amount of the standard sample that can be used in one tuning is also limited, and it is not possible to perform many items of tuning in one tuning. . Therefore, the present invention improves the operability of tuning, enables the introduction of a large amount of standard sample, enables tuning of many items in one tuning, and maintains a constant cycle even during continuous analysis performed as a routine. It is an object of the present invention to enable automatic tuning such as performing tuning or performing tuning at an arbitrary time. [0007] A liquid chromatograph / mass spectrometer according to the present invention comprises a standard sample accommodating section accommodating a standard sample used for tuning, a syringe pump section, a flow path switching section, and a control section. Section. The syringe pump unit includes a syringe pump that sucks in and sends out the standard sample in the standard sample storage unit. The flow path switching unit is provided between the interface unit of the mass spectrometer and the liquid chromatograph, and switches and connects the interface unit to a liquid chromatograph or a syringe pump unit. The control unit is
Among the operations of the mass spectrometer, at least the tuning operation is controlled.At the time of normal analysis, the interface is connected to the liquid chromatograph, at the time of tuning, the interface is connected to the syringe pump, and the standard sample is supplied by the syringe pump. The operations of the channel switching unit and the syringe pump unit are controlled so that the standard sample in the storage unit is supplied to the interface unit. When the control section starts the operation of auto-tuning, the syringe pump section automatically sucks a standard sample into the syringe, the syringe pump section is connected to the mass spectrometer, and the syringe pump section operates to control the standard from the syringe. The sample is sent out and introduced into the mass spectrometer. Embodiment 1 FIG. 1 schematically shows a first embodiment. Reference numeral 2 denotes a mass spectrometer unit, and an eluate from a column of the liquid chromatograph 6 or a standard sample from a syringe pump unit is supplied from an interface (I / F) unit 2a via a four-way valve 4 in a flow path switching unit. . In order to perform mass analysis of the eluate component or the standard sample supplied to the interface unit 2a, a convergent lens system 2b for ionizing the sample and sending out the ions, a mass filter 2c for separating the ions by mass number, and A detector 2d for detecting ions. The four-way valve 4 has a first port connected to the interface 2a of the mass spectrometer unit, a second port connected to the column outlet of the liquid chromatograph 6,
The drain for drain is connected to the third port, and the liquid feed port of the syringe pump unit 10 is connected to the fourth port.
The four-way valve 4 switches between a flow path indicated by a solid line and a flow path indicated by a broken line. The syringe pump section 10 includes a syringe pump composed of a syringe 14 and a motor 15, and a three-way valve 12 as a flow path switching section. The syringe pump performs suction and discharge of liquid by moving the plunger of the syringe 14 at a constant speed by the motor 15. Reference numeral 16 denotes a standard sample container containing a standard sample. A syringe 14 is connected to a first port of the three-way valve 12, a standard sample container 16 is connected to the second port, a liquid feed port is connected to the third port, and the liquid feed port is connected to a four-way valve. 4 is connected to the fourth port. The three-way valve 12 switches between a solid line flow path and a broken line flow path. The control unit 18 controls the operation of the mass spectrometer unit 2, and controls the switching operation of the four-way valve 4, the switching operation of the three-way valve 12 of the syringe pump unit 10, and the suction and discharge operations of the syringe pump. Things. Next, the operation of this embodiment will be described. (1) The four-way valve 4 is set to the flow path indicated by the broken line by the normal analysis control unit 18, and the liquid chromatograph 6 is connected to the mass spectrometer unit 2. The syringe pump unit 10 does not operate. (2) Auto-tuning The syringe pump unit 10 starts operating while the liquid chromatograph 6 and the mass spectrometer unit 2 remain connected. In the syringe pump section 10, the three-way valve 12 is set at the position indicated by the solid line to connect the ports 1 and 2, and the plunger of the syringe 14 retreats to suck the standard sample in the standard sample container 16 into the syringe 14. Next, the four-way valve 4 is switched to a straight flow path so that the syringe pump section 10 is connected to the mass spectrometer section 2. Then, the three-way valve 12 is switched to the flow path indicated by the broken line, the plunger of the syringe 14 is pushed in, and the standard sample is introduced into the mass spectrometer unit 2. The introduction speed and the introduction amount at this time are set by the control unit 18. Then, the auto-tuning is performed in the mass spectrometer unit 2. The switching of the flow path in the syringe pump section 10 and the suction and discharge of the standard sample, the switching of the flow path of the four-way valve 4, and the auto-tuning operation in the mass spectrometer section 2 are all performed by a common control section 18. Controlled. As a method of injecting the standard sample, the standard sample first sucked into the syringe 14 is discarded into the drain 8 and the second and subsequent times.
May be controlled so as to introduce the standard sample sucked into the mass spectrometer unit 2. (Embodiment 2) FIG. 2 schematically shows a second embodiment. Compared to the first embodiment, the function of both the four-way valve 4 and the three-way valve 12 is realized by one six-way valve 20. In FIG.
The liquid chromatograph 6 is connected to the first port of the six-way valve 20.
Is connected, the interface of the mass spectrometer unit 2 is connected to the second port, the syringe pump 14 of the syringe pump unit 10 is connected to the third port, and the standard sample container 16 is connected to the fourth port. , The fifth port is closed and the sixth port is connected to the drain. During normal analysis, the six-way valve 20 is set to the flow path shown by the solid line, and the column effluent of the liquid chromatograph 6 is supplied to the mass spectrometer unit 2. At the time of auto-tuning, when the operation of auto-tuning is started, the syringe pump unit 10 starts operating and the standard sample in the standard sample container 16 is sucked into the syringe pump 14 with the six-way valve 20 remaining in the flow path of the solid line. . Thereafter, the six-way valve 20 is switched to the flow path indicated by the broken line, and the syringe pump 1
4 plunger is pushed in and the standard sample is
Is supplied to the auto-tuning unit. The switching operation of the six-way valve 20 and the operation of sucking and discharging the standard sample by the syringe pump 14 in the syringe pump section 10 are controlled to control the operation of the mass spectrometer section 2 as in the first embodiment. It is controlled by the unit 18. As an operation common to the first embodiment and the second embodiment, when one standard sample suction amount by the syringe 14 is not enough, the discharge end position of the syringe 14 is detected by a microswitch or the like. Alternatively, the standard sample can be sucked again into the syringe 14 and re-injected into the mass spectrometer unit 2. In the analysis using a liquid chromatograph / mass spectrometer, there is an analysis method called infusion analysis in which an unknown sample is manually directly injected into a mass spectrometer. The device of the present invention can also be used for its infusion analysis. In this case, after the analysis sample is manually sucked into another syringe, the sample is attached to the position of the syringe 14 of the syringe pump unit 10, and the analysis sample is injected into the mass spectrometer unit 2 via the three-way valve 12 and the four-way valve 4. . According to the present invention, a standard sample used for tuning is stored in a standard sample storage unit, and the standard sample can be supplied by a syringe pump unit.
The mass spectrometer is configured so that the syringe pump and the liquid chromatograph can be switched and connected by a flow path switching unit, and the operation of the syringe pump unit, the switching of the flow path connected to the mass spectrometer, and the mass spectrometer. The tuning operation is controlled by a common control unit. As a result, it is not necessary to set a syringe pump for injecting a standard sample or a pipe from the syringe pump to the mass spectrometer every time tuning is performed, and operability is improved. The tuning can be performed even during the routine analysis for performing the normal analysis, and the tuning operation of the mass spectrometer and the injection operation of the standard sample can be commonly controlled, so that the auto tuning can be performed. become. In addition, since the standard sample in the standard sample container can be repeatedly injected with the syringe, the tuning of the standard sample can be performed with a single tuning without being restricted by the injection amount of the standard sample.

[Brief description of the drawings] FIG. 1 is a schematic configuration diagram showing a first embodiment. FIG. 2 is a schematic configuration diagram showing a second embodiment. [Explanation of symbols] 2 Mass spectrometer section 2a Interface section 4 Four-way valve 6 liquid chromatograph 10 Syringe pump section 12 Three-way valve 14 syringe 16 Standard sample container 18 Control unit 20 Hex valve

Claims (1)

(1) A liquid chromatograph / mass spectrometer for introducing a column eluate of a liquid chromatograph into a mass spectrometer via an interface section of the mass spectrometer. A standard sample storage unit that stores a standard sample used for tuning, a syringe pump unit that includes a syringe pump that sucks in and sends out the standard sample in the standard sample storage unit, and is provided between a liquid chromatograph and the interface unit. A flow path switching unit that switches and connects the interface unit to a liquid chromatograph or the syringe pump unit; and controls at least a tuning operation among operations of the mass spectrometer. Connect to the graph. An auto-tuning operation by controlling the operation of the flow path switching unit and the syringe pump unit so as to be connected to the syringe pump unit and supply the standard sample in the standard sample storage unit to the interface unit by the syringe pump unit. And a common controller for performing the following.