JP2002277451A - Liquid chromatograph - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid chromatograph capable of reducing burden on an operator on the replenishment of a mobile phase in continuous analysis. SOLUTION: The liquid chromatograph is provided with a plurality of mobile- phase containers 1 and 2 constituted in such a way as to be switched and used by a mobile-phase switching part 8 comprised of a valve. One of the mobile- phase containers is first used to perform continuous analysis, and the required quantity of the mobile phase for the next analysis is collated with the remaining quantity of the mobile phase in the mobile-phase container in use before the start of each analysis. When the former exceeds the latter, the start of the next analysis is temporarily postponed, and the valve is operated to automatically switch to another mobile-phase container. By this, as it is satisfactory that the operator first prepares the mobile-phase in the mobile-phase container of a relatively small capacity, starts continuous analysis, and then prepares the mobile phase for replenishment in another mobile-phase container as occasion demands, it is not necessary for the operator to check the remaining quantity of the mobile phase by himself to determine whether replenishment is necessary or not or to be urged by an alarm and pressed by replenishing work to reduce the work burden.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid chromatograph, and more particularly to a liquid chromatograph equipped with an autosampler for performing continuous analysis.

[0002]

2. Description of the Related Art In liquid chromatography, analysis is performed while a mobile phase previously stored in a mobile phase container is sent to a column by a liquid sending pump unit. In continuous analysis in which a large number of samples are successively analyzed by an autosampler. However, there is a possibility that the analysis cannot be performed due to a shortage of the mobile phase in the middle.
As the simplest solution in principle to prevent such a situation, it is thought that it is sufficient to first prepare a large amount of mobile phase more than the required amount of mobile phase required until the end of continuous analysis, It is not practical to prepare a large amount of solution at one time, and to transport and install the solution, because the workload of the operator is extremely large.

For this purpose, conventionally, the amount of liquid supplied from the liquid supply pump unit from the time when the mobile phase container is full is integrated, and the integrated value is subtracted from the full value of the container, that is, the remaining amount of mobile phase. There has been a system that allows the operator to refer to this to determine the replenishment time of the mobile phase. Furthermore, as a system developed from this, the required amount of mobile phase in the next analysis is calculated, and this is compared with the mobile phase remaining amount calculated above, and when the former exceeds the latter, the start of the next analysis is temporarily stopped. In some cases, a stop (that is, continuous analysis is interrupted) and an alarm is issued to prompt the operator to replenish the mobile phase (Japanese Patent Laid-Open No. 2000-29811).
2).

[0004]

In the system provided with the mobile phase remaining amount display function, the operator checks the displayed mobile phase remaining amount in a timely manner and replenishes the mobile phase at an appropriate time according to his own judgment. In addition, in a system with an alarm function, when an alarm is received, the work of replenishing the mobile phase must be performed immediately prior to other work, which is a burden on the operator. there were.

[0005] In addition, in the work of replenishing the mobile phase, if the liquid is added at any time during the analysis, the analysis state may be slightly different and the data may be affected, so that the analysis in progress is terminated. And then replenish the solution, then wait until the old mobile phase remaining inside the liquid chromatograph is completely replaced by the newly replenished mobile phase before starting the next analysis. Therefore, it is very troublesome and troublesome for the operator.

The present invention has been made in view of such circumstances, and has as its object to provide a liquid chromatograph which can solve the above-mentioned problems relating to the replenishment of the mobile phase and can reduce the burden on the operator. And

[0007]

In order to solve the above-mentioned problems, the present invention comprises a plurality of mobile phase containers which can be switched and used by a mobile phase switching section comprising a valve. Continuous analysis was performed using the mobile phase containers, and before the start of each analysis, the required amount of mobile phase in the next analysis was compared with the remaining mobile phase in the mobile phase container in use, and the former exceeded the latter. In some cases, the start of the next analysis was temporarily postponed, and the valve was operated to automatically switch to another mobile phase container.

That is, the apparatus of the present invention comprises a plurality of mobile phase containers, a mobile phase switching unit for selectively connecting one of the mobile phase containers to the liquid sending pump unit, and a remaining amount of the mobile phase in the mobile phase container. A mobile phase remaining amount calculating means for calculating the required amount of mobile phase used in the next analysis based on the amount of liquid sent from the liquid sending pump unit and the analysis program; and Determine whether to switch the mobile phase container based on the value of the remaining mobile phase and the required mobile phase,
A liquid chromatograph comprising: a mobile phase switching control unit for instructing the start of the next analysis in accordance with the determination result or for instructing the mobile phase switching unit to switch to another mobile phase container.

Thus, the operator first prepares the mobile phase in a relatively small-volume mobile phase container to start continuous analysis, and then prepares a supplementary mobile phase in another mobile phase container as needed. Therefore, the operator does not have to check the remaining amount of the mobile phase in a timely manner to judge whether or not the replenishment is necessary, and the operator is not prompted by the alarm to pursue the replenishment work, thereby reducing the work load.

[0010]

FIG. 1 shows an embodiment of the present invention. In the figure, reference numerals 1 and 2 denote mobile phase containers for storing a mobile phase of a liquid chromatograph. The mobile phase is sent to a column 5 at a predetermined flow rate by a liquid sending pump unit 3. The sample to be analyzed is introduced into the flow of the mobile phase from the automatic sample introduction unit (autosampler) 4, separated into components while passing through the column 5, detected by the detector unit 6 as an electric signal, and It is processed and recorded by a data processing device that does not. The column 5 is housed in a column oven 7 and maintained at a predetermined temperature for analysis.

The mobile phase switching unit 8 comprises a valve for selectively selecting one of the two mobile phase containers 1 and 2 and connecting to the liquid sending pump unit 3, and switches the mobile phase containers 1 and 2. At this time, by opening the purge valve 9, the mobile phase before switching remaining in the liquid feed pump unit 3 and the flow paths before and after the liquid pump unit 3 is discharged to promote the replacement with the new mobile phase.

The controller 10 controls the liquid chromatograph system consisting of the above items 1 to 9 in total, and includes an analysis of the amount of liquid sent from the liquid pump 3 and the temperature of the column oven 7. A program control unit 11 that stores a program and controls each unit according to the program is included. In addition to the above, the mobile phase required amount calculation unit 13 which calculates the amount of mobile phase required for the next analysis (mobile phase required amount) from the stored analysis program in the controller 10,
A mobile phase consumption calculator 14 for calculating the mobile phase consumption by integrating the liquid feeding amount of the liquid sending pump unit 3, and subtracting the mobile phase consumption from the capacity of the mobile phase container 1 or 2 to obtain the remaining mobile phase; The required mobile phase remaining amount calculation unit 15 compares the required mobile phase amount with the mobile phase remaining amount, and instructs switching of the mobile phase container or instructs the start of the next analysis based on the comparison result. A control unit 16 is included.

The operation of the embodiment shown in FIG. 1 will now be described. As an initial state, the liquid-feeding pump unit 3 is operated after the mobile-phase container 1 connected to the liquid-feeding pump unit 3 via the mobile-phase switching unit 8 is fully filled with the mobile phase. The analysis is started by injecting a sample from the automatic sample introduction unit 4 under the control of the program control unit 11. The injected sample is carried to the column 5, and each component in the sample separated here reaches the detector unit 6 sequentially and is detected. It usually takes several tens of minutes until the detection of the last component is completed, and one analysis is completed, and the next analysis is started by successively introducing the next sample. Note that a series of analyzes performed continuously in this manner is referred to as a continuous analysis herein, and one analysis is simply referred to as “analysis” to distinguish between the two.

The management of the mobile phase during the continuous analysis is performed as follows. The mobile phase consumption calculating unit 14 obtains the liquid feeding amount information f of the liquid feeding pump unit 3 from the program control unit 11, calculates the mobile phase consumption e by integrating the obtained information with time, and converts the value into the mobile phase consumption value. It is sent to the remaining amount calculating section 15, where the mobile phase remaining amount c is calculated by subtracting the mobile phase consumption amount e from the capacity value h of the mobile phase container 1. Although not shown, the calculated value of the remaining mobile phase c can be displayed on a display device in the same manner as in the related art. The capacity value h is input and set in advance in accordance with the capacity of the mobile phase container to be used.

Prior to the start of the analysis, the mobile phase required amount calculation unit 1
3 obtains information g on the mobile phase flow rate and the analysis time from the program control section 11 and obtains the required mobile phase amount d in the next analysis.
Is sent to the mobile phase switching control section 16 together with the mobile phase remaining amount c, where the two are compared.
As a result of the comparison, when the mobile phase remaining amount c is larger than the mobile phase required amount d, an analysis start signal a is transmitted, and the program control unit 11 receiving the analysis start signal executes the analysis as described above. If the remaining mobile phase c is smaller than the required mobile phase amount d (that is, if it is determined that there is no mobile phase in the middle of the next analysis), the start of the next analysis is postponed, and the mobile phase switching unit is started. A signal b for switching the valve is sent to 8 and the mobile phase container is switched from 1 to 2. (The operator must fill the mobile phase container 2 with the replenishing mobile phase by this time.)

At the same time, a reset signal r is sent to the mobile phase consumption calculator 14 and the mobile phase remaining calculator 15 to reset them. At this time, the purge valve 9 is also operated in conjunction with the switching of the mobile phase, so that the mobile phase supplied from the mobile phase container 2 can quickly replace the liquid sending pump section 3 and the flow path around it. After the purge for a predetermined period of time, after waiting for a while until the old mobile phase in the flow path after the purge valve 9 is replaced and the baseline of the detector unit 6 is stabilized, the analysis start signal a is sent and the continuous analysis is performed. Resume. The waiting time until stabilization is set in the program in advance.

FIG. 2 is a flowchart showing the above sequence. Since the flow of the operation shown in the figure is as described above, the description is not repeated.

As described above, in this embodiment, when the mobile phase in the used mobile phase container is almost exhausted, the mobile phase container is automatically switched to another mobile phase container, and the mobile phase is switched during the analysis. The analysis data is not adversely affected. As a result, continuous analysis can be continued, although a slight stabilization wait time is required after the mobile phase switching. Since the operator only needs to replenish the mobile phase container to the unused mobile phase container at any time, the work load is significantly reduced.

As a method for obtaining the remaining mobile phase, in addition to the above example, since the rotation speed of the liquid sending pump unit 3 is proportional to the liquid sending amount, the number of rotations of the liquid sending pump unit 3 is counted and moved. There is also a method of calculating the phase consumption and calculating the remaining mobile phase from this.
Alternatively, a liquid level gauge or the like may be installed in the mobile phase container to directly determine the remaining amount. That is, as shown by a chain line in FIG. 1, the mobile phase consumption calculator 14 and the remaining mobile phase calculator 15 can be comprehensively represented as the mobile phase remaining calculator 12.

The purge valve 9 is an effective means for accelerating the displacement of the mobile phase, but can be omitted if the stabilization time can be prolonged. This is not an essential requirement in the configuration of the present invention because it can be substituted if it exists. Although the column 5 is usually used in the column oven 7 as in the above-described example, when the column temperature is analyzed at room temperature or the like, even if the column oven 7 is omitted, there is no problem in the configuration of the present invention. Absent.

FIG. 1 illustrates a case where two mobile phase containers are used. However, it is also possible to use three or more mobile phase containers. In this case, there is a time margin for replenishing the mobile phase. And the burden on the operator is further reduced.

[0022]

As described in detail above, the present invention comprises a plurality of mobile phase containers configured to be switchable and usable by a valve. First, continuous analysis is performed using one of the mobile phase containers. Before the start of each analysis, the required amount of mobile phase in the next analysis is compared with the remaining amount of mobile phase in the mobile phase container in use, and if the former exceeds the latter, the start of the next analysis is temporarily postponed and Since the valve is operated to automatically switch to another mobile phase container, the operator first prepares a mobile phase in a relatively small-volume mobile phase container, starts continuous analysis, and thereafter, at any time, It is sufficient to prepare a mobile phase for replenishment in another mobile phase container, so the operator can check the remaining amount of mobile phase in a timely manner to judge the necessity of replenishment, Will not be chased, Work load is reduced.

[Brief description of the drawings]

FIG. 1 is a diagram showing one embodiment of the present invention.

FIG. 2 is a flowchart illustrating the operation of the present invention.

[Explanation of symbols]

 1, 2 mobile phase container 3 liquid sending pump unit 4 automatic sample introduction unit 5 column 6 detector unit 7 column oven 8 mobile phase switching unit 9 purge valve 10 controller 11 program control unit 12 Mobile phase remaining amount calculation means

Claims (1)

[Claims] 1. A column for separating a sample, a liquid sending pump for sending a mobile phase to the column, a mobile phase container containing a mobile phase, and a flow path between the liquid sending pump and the column. An automatic sample introduction unit for introducing a sample into a mobile phase, a detector unit for detecting a separated component in a sample eluted from the column, and an analysis program are stored, and the respective units are controlled according to the analysis program to perform continuous analysis. A liquid phase chromatograph comprising: a plurality of the mobile phase containers; and a mobile phase switching unit that selectively connects one of the mobile phase containers to the liquid sending pump unit. Mobile phase remaining amount calculating means for obtaining the remaining amount of the mobile phase in the mobile phase container;
A mobile phase required amount calculating unit for calculating a required amount of a mobile phase to be used in the next analysis based on a liquid sending amount of the liquid sending pump unit and the analysis program, and a mobile phase remaining amount and a mobile phase required amount calculated by these; It is determined whether or not the mobile phase container should be switched based on the value of the amount and, based on the determination result, the next analysis start is commanded or the mobile phase switching unit is commanded to switch to another mobile phase container. A liquid chromatograph comprising a mobile phase switching control unit.