Liquid delivery unit, liquid chromatography analysis system and control method thereof

Abstract

The present invention relates to a liquid delivery unit and a liquid chromatography analysis system and a control method thereof. A first solution is supplied from a first pump. A second solution is supplied from a second pump. The flow path from the first pump and the second pump to a column is switched between the first flow path and the second flow path. In the first flow path, a first mixer is located at an upstream side of an injection portion of an injector, and a second mixer is located at a downstream side of the injection portion. In the second flow path, both the first mixer and the second mixer are located at an upstream side of the injection portion. The first flow path is formed in a first mode in which a sample is diluted before being introduced into a column. The second flow path is formed in a second mode in which a sample is not diluted before being introduced into a column.

Description

Technical Field

[0001] The present disclosure relates to a liquid chromatography analysis system that provides a mobile phase according to a gradient elution method. Background Art

[0002] Gradient elution is an analytical method that uses a mixture of multiple solvents as a mobile phase in liquid chromatography. In the past, there was a system that had a structure for supplying a mobile phase according to the gradient elution method. In addition, in the past, there was a system that had a structure for diluting a sample before it was introduced into a column.

[0003] Technologies related to the system described above are disclosed, for example, in Patent Document 1 (U.S. Patent Application Publication No. 2002 / 117447), Patent Document 2 (U.S. Patent Application Publication No. 2004 / 035789), Patent Document 3 (U.S. Patent Application Publication No. 2008 / 264848), and Patent Document 4 (U.S. Patent Application Publication No. 2010 / 176043).

[0004] However, in the case where the conventional system includes a configuration for diluting the sample before introducing the sample into the column, it is not suitable for analysis in a mode in which the sample is not diluted before introducing the sample into the column.

[0005] Therefore, a technology for making a liquid chromatography analysis system suitable for both analysis in a mode in which a sample is diluted before introduction into a column and analysis in a mode in which a sample is not diluted before introduction into a column is sought. Summary of the invention

[0006] A liquid delivery unit according to one aspect of the present disclosure is a liquid delivery unit that delivers a first solution and a second solution as mobile phases to a column of a liquid chromatography analysis system. The first solution is supplied from a first pump. The second solution is supplied from a second pump. The liquid chromatography analysis system includes an injection portion for sample injection. The liquid delivery unit includes: a first mixer; a second mixer; and a switching device that switches the flow path from the first pump and the second pump to the column between the first flow path and the second flow path. The first flow path and the second flow path include a first mixer and a second mixer, respectively. In the first flow path, the first mixer is located at a position upstream of the injection portion, and the second mixer is located downstream of the injection portion. In the second flow path, both the first mixer and the second mixer are located upstream of the injection portion. The switching device configures the first flow path as a flow path in a first mode in which the sample is diluted before being introduced into the column, and configures the second flow path as a flow path in a second mode in which the sample is not diluted before being introduced into the column.

[0007] A liquid chromatography analysis system according to a certain aspect of the present disclosure is a liquid chromatography analysis system that uses a first solution and a second solution as mobile phases. The liquid chromatography analysis system includes: a column; a first pump that supplies a first solution; a second pump that supplies a second solution; an injector that injects a sample toward the column; a first mixer; a second mixer; and a switching device that switches the flow path from the first pump and the second pump to the column between the first flow path and the second flow path. The first flow path and the second flow path include a first mixer and a second mixer, respectively. In the first flow path, the first mixer is located at a position upstream of an injection portion where the injector injects the sample, and the second mixer is located downstream of the injection portion. In the second flow path, both the first mixer and the second mixer are located upstream of the injection portion. The switching device configures the first flow path as a flow path in a first mode in which the sample is diluted before being introduced into the column. In the second mode in which the sample is not diluted before being introduced into the column, the second flow path is configured as the flow path.

[0008] A control method for a liquid chromatography analysis system in a certain aspect of the present disclosure is a control method for a liquid chromatography analysis system that uses a first solution and a second solution as a mobile phase and is executed by a computer. The control method includes the following steps: obtaining an analysis mode; and controlling the flow path from a first pump that supplies a first solution and a second pump that supplies a second solution to a column of the liquid chromatography analysis system according to the analysis mode. The liquid chromatography analysis system includes an injection portion for sample injection, a first mixer, and a second mixer. The step of controlling the flow path includes the following steps: when the analysis mode is a first mode in which the sample is diluted before being introduced into the column, the flow path is controlled so that the first mixer is located at a position upstream of the injection portion and the second mixer is located downstream of the injection portion. The step of controlling the flow path includes the following steps: when the analysis mode is a second mode in which the sample is not diluted before being introduced into the column, the flow path is controlled so that both the first mixer and the second mixer are located upstream of the injection portion. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 2 is a diagram showing a schematic configuration of an LC system 100 according to the present disclosure.

[0010] Figure 2 It is a diagram showing the position of the liquid supply unit 13 in the standard mode.

[0011] Figure 3 It is a diagram showing the position of the liquid supply unit 13 in the dilution mode.

[0012] Figure 4 It is a diagram showing a specific example of the structure of a liquid feeding unit according to the conventional technology.

[0013] Figure 5 It is a diagram showing a specific example of the structure of a liquid feeding unit according to the conventional technology.

[0014] Figure 6 It is a diagram showing a specific example of the structure of a liquid feeding unit according to the conventional technology.

[0015] Figure 7 It is a diagram showing a specific example of the structure of a liquid feeding unit according to the conventional technology.

[0016] Figure 8 It is a diagram showing evaluations on five criteria for the configuration of the present embodiment and the configuration according to the conventional technology.

[0017] Fig. 9 It is a diagram showing an example of a specific structure of the liquid supply unit 13 .

[0018] Fig.10 1 is a diagram showing an example of the connection form of the ports 601 to 606 in the standard position of the flow path switching valve 600 .

[0019] Fig.11 1 is a diagram showing an example of the connection form of the ports 601 to 606 of the flow path switching valve 600 at the dilution position.

[0020] Fig.12 is a flow chart of the processing performed by the LC system 100 to analyze a sample. DETAILED DESCRIPTION

[0021] A liquid chromatography analysis system (hereinafter referred to as "LC system") according to an embodiment of the present disclosure is described in detail below with reference to the drawings. In addition, the same reference numerals are attached to the same or corresponding parts in the drawings, and their description will not be repeated.

[0022] [Schematic structure of liquid chromatography analysis system]

[0023] Figure 1 1 is a diagram showing a schematic structure of the LC system 100 of the present disclosure. Figure 1 As shown, the LC system 100 includes a liquid delivery unit 10 , an automatic sample injector 20 , a column oven 30 , a detector 40 , an analysis channel 50 , and a controller 60 .

[0024] The LC system 100 has a structure for supplying a mobile phase according to a gradient elution method. In the LC system 100, a first solvent and a second solvent are prepared as solvents constituting the mobile phase. A tank 71 storing the first solvent and a tank 72 storing the second solvent are connected to the liquid supply unit 10.

[0025] The first solvent and the second solvent have different elution powers. In one embodiment, the first solvent is water and the second solvent is methanol. The liquid supply unit 10 supplies a mobile phase according to a gradient elution method to the analysis channel 50 by mixing the first solvent and the second solvent.

[0026] The liquid delivery unit 10 includes a first pump 11 for supplying a first solvent to the analysis flow path 50 and a second pump 12 for supplying a second solvent to the analysis flow path 50. The controller 60 adjusts the flow rates of the first and second solvents in the mobile phase by controlling the flow rates of the first and second pumps 11, 12, respectively, thereby adjusting the ratio of the first and second solvents in the mobile phase.

[0027] The liquid supply unit 10 further includes a liquid supply unit 13 for mixing the first solvent supplied from the first pump 11 and the second solvent supplied from the second pump 12. Figure 2 and Figure 3 The detailed structure of the liquid supply unit 13 will be described.

[0028] The automatic sampler 20 injects a sample into the analysis channel 50 .

[0029] The column oven 30 includes a column 31. The column 31 is used to separate a sample injected into the analysis channel 50 by the autosampler 20. The column 31 is accommodated in the column oven 30. The column oven 30 controls the temperature of the column 31 to a preset temperature.

[0030] The detector 40 is a device for detecting one or more components separated from the sample in the column 31. The detector 40 acquires detection signals based on the one or more components separated in the column 31, and transmits the detection signals to the controller 60.

[0031] The controller 60 controls the operations of the liquid feeding unit 10 , the automatic sample injector 20 , and the column oven 30 , and creates various calculations and chromatograms based on the detection signal obtained by the detector 40 .

[0032] The controller 60 includes a processor 61, a storage device 62, and an interface 63. The processor 61 performs the above-mentioned operation control and the calculation for the preparation of the chromatogram. The storage device 62 stores the program and data for the above-mentioned calculation. The interface 63 functions as a communication interface between the liquid supply unit 10, the automatic sample injector 20, and the column oven 30 and the processor 61, respectively.

[0033] [Standard mode and diluted mode]

[0034] In order to adjust the peak shape of the chromatogram generated for the sample, the sample is sometimes diluted. In this specification, in the LC system 100, the analysis mode when analyzing the sample without diluting it is called "standard mode", and the analysis mode when analyzing the diluted sample is called "dilution mode".

[0035] The “dilution mode” is an example of a first mode in which the sample is diluted before being introduced into the column 31 . The “standard mode” is an example of a second mode in which the sample is not diluted before being introduced into the column 31 .

[0036] [Schematic structure of liquid delivery unit]

[0037] In the LC system 100 , the liquid sending unit 13 is located so as to form different paths in the standard mode and the dilution mode. Figure 2 It is a diagram showing the position of the liquid supply unit 13 in the standard mode. Figure 2 The position shown is also called the "standard position". Figure 3 It is a diagram showing the position of the liquid supply unit 13 in the dilution mode. Figure 3 The position shown is also referred to as the "dilution position".

[0038] like Figure 2 and Figure 3 As shown, the liquid supply unit 13 includes a first mixer 13G and a second mixer 13D. The first mixer 13G and the second mixer 13D each include a mixing chamber for accommodating liquids supplied from a plurality of supply sources. An opening is formed in the mixing chamber for discharging the liquids supplied from the plurality of supply sources in a mixed state. In one embodiment, the first mixer 13G and the second mixer 13D are each implemented using a gradient mixer manufactured by Shimadzu Corporation (https: / / www.an.shimadzu.co.jp / hplc / prominence / modules / 8_option.htm). The mixing capacity of each of the first mixer 13G and the second mixer 13D is based on the capacity of the mixing chamber each has.

[0039] exist Figure 2 In the example of , the liquid delivery unit 13 includes tubes 131 to 134. Figure 2 In the example of , the tubes 131 to 134 constitute a flow path from the first pump 11 and the second pump 12 to the column 31 in the analysis flow path 50 .

[0040] exist Figure 3 In the example of , the liquid delivery unit 13 includes tubes 131, 132, and 134 to 136. Figure 3 In the example of FIG. 1 , the tubes 131 , 132 , and 134 to 136 constitute a flow path from the first pump 11 and the second pump 12 to the column 31 in the analysis flow path 50 .

[0041] ( Figure 2 : Standard position)

[0042] exist Figure 2In the standard position shown, the first solvent supplied from the first pump 11 is introduced into the second mixer 13D via the tube 131, and then introduced into the first mixer 13G via the tube 133. On the other hand, the second solvent supplied from the second pump 12 is introduced into the first mixer 13G via the tube 132. The first solvent and the second solvent are mixed in the first mixer 13G, and then introduced into the column 31 via the tube 134 and the tube 135.

[0043] exist Figure 2 In FIG. 1 , as “automatic sample injector 20 ”, an injection portion in the analysis flow path 50 for injecting a sample from the automatic sample injector 20 is shown. Figure 2 In the process, the sample injected from the automatic sampler 20 is introduced into the column 31 through the tube 135.

[0044] exist Figure 2 In the standard position shown, the first solvent supplied from the first pump 11 passes through the first mixer 13G after passing through the second mixer 13D, and then passes through (the injection portion of) the automatic sampler 20. That is, both the first mixer 13G and the second mixer 13D are located upstream of (the injection portion of) the automatic sampler 20.

[0045] exist Figure 2 , which is used to illustrate the liquid delivery form in the standard mode. Note N1 includes a graph showing the liquid delivery form to the analysis flow path 50 before and after the sample is injected from the automatic sampler 20. In the graph, the vertical axis schematically shows the flow rate of each solution at the sample introduction port of the analysis flow path 50, and the horizontal axis shows time.

[0046] As shown in the diagram of note N1, the driving of the first pump 11 and the second pump 12 starts at time T0. Thus, the first solvent and the second solvent start to be supplied to the analysis flow path 50. Thereafter, from time T1 to time T2, the sample is introduced from the automatic sampler 20 to the analysis flow path 50. Specifically, the valve in the automatic sampler 20 is switched, and the sample filled in the sample loop similarly arranged in the automatic sampler 20 is introduced into the analysis flow path 50 at the flow rate set at time T0.

[0047] If the introduction of the sample is completed at time T2, then Figure 2 In the example, the flow rate ratio of the first solvent and the second solvent after time T2 is constant, but in reality, the flow rate ratio of the first solvent and the second solvent after time T2 may vary based on the setting used in the analysis of the sample (setting according to the gradient elution method).

[0048] ( Figure 3 : Dilution position)

[0049] exist Figure 3At the dilution position shown, the first solvent supplied from the first pump 11 is introduced into the second mixer 13D via the tube 131. On the other hand, the second solvent supplied from the second pump 12 is introduced into the first mixer 13G via the tube 132, and then introduced into the second mixer 13D via the tubes 134 and 135.

[0050] exist Figure 3 At the dilution position shown, the first solvent and the second solvent are mixed in the second mixer 13D and then introduced into the column 31 through the tube 136 .

[0051] exist Figure 3 In, with Figure 2 Likewise, as the “autosampler 20”, an injection portion in the analysis flow path 50 that injects a sample from the autosampler 20 is shown. Figure 3 At the dilution position shown, the sample injected from the autosampler 20 is introduced into the second mixer 13D via the tube 135. Then, the sample is diluted with the first solvent in the second mixer 13D and then introduced into the column 31 via the tube 136.

[0052] exist Figure 3 At the dilution position shown, the second solvent supplied from the second pump 12 passes through the first mixer 13G, then passes through the automatic sampler 20 (the injection portion), and then passes through the second mixer 13D. That is, the first mixer 13G is located at the upstream side of the automatic sampler 20 (the injection portion), and the second mixer 13D is located at the downstream side of the automatic sampler 20 (the injection portion).

[0053] exist Figure 3 Attachment N2 for explaining the liquid supply form in the dilution mode is shown in FIG. Attachment N2 includes a graph showing the liquid supply form to the analysis flow path 50 before and after the sample is injected from the autosampler 20. In the graph, the vertical axis schematically shows the flow rate, and the horizontal axis shows time.

[0054] As shown in the diagram of the note N2, the driving of the first pump 11 and the second pump 12 starts at time T0. Thus, the first solvent and the second solvent start to be supplied to the analysis flow path 50. Thereafter, from time T1 to time T2, the valve in the automatic sampler 20 is switched, and the sample filled in the sample loop similarly arranged in the automatic sampler 20 is pushed out by the second solvent delivered by the driving of the second pump 12, thereby introducing the sample into the analysis flow path 50. Thus, the pushed out sample is diluted by the first solvent delivered by the driving of the first pump 11, and the diluted sample is introduced into the column 31.

[0055] When the introduction of the sample is completed at time T2, a mixed solution of the first solvent and the second solvent mixed at a predetermined ratio is supplied to the analysis flow path 50. Figure 3In the example, the flow rate ratio of the first solvent and the second solvent after time T2 is constant, but in reality, the flow rate ratio of the first solvent and the second solvent after time T2 may vary based on the setting used in the analysis of the sample (setting according to the gradient elution method).

[0056] [Specific example of the structure according to the prior art]

[0057] Figures 4 to 7 Each of the figures shows a specific example of the structure of the liquid delivery unit according to the prior art. Each specific example will be described below.

[0058] ( Figure 4 : Bypass mode)

[0059] Figure 4 The structural example includes a first mixer 913G and a second mixer 913D. Figure 4 The column oven 930 also includes a first pump 911 , a second pump 912 , tubes 811 , 812 , 813 , 814 , 815 , 816 , an automatic sample injector 920 , and a column oven 930 . The column oven 930 includes a column 931 .

[0060] exist Figure 4 In the structural example, the first solvent supplied from the first pump 911 is introduced into the first mixer 913G via the tube 811. The second solvent supplied from the second pump 912 is introduced into the first mixer 913G via the tube 812. The first solvent and the second solvent are mixed in the first mixer 913G and then introduced into the column 931 via the tube 813 and the tube 816.

[0061] The sample injected from the automatic sampler 920 is introduced into the second mixer 913D via the tube 815 .

[0062] exist Figure 4 In the configuration example, the tube 814 functions as a bypass line. That is, a portion of the mixed liquid (the first solvent and the second solvent) in the tube 813 is introduced into the second mixer 913D via the tube 815, but the remaining portion is introduced into the second mixer 913D via the tube 814.

[0063] The mixed solution introduced into the second mixer 913D via the tube 814 dilutes the sample from the automatic sampler 920. The diluted sample is introduced from the second mixer 913D via the tube 816 into the column 931.

[0064] exist Figure 4 , which is used to explain the liquid delivery form in the dilution mode. Note N3 includes a graph showing the liquid delivery form to the analysis flow path (tubes 811 to 816) before and after the sample is injected from the automatic sampler 920. In the graph, the vertical axis schematically represents the flow rate, and the horizontal axis represents time.

[0065] As shown in the diagram of note N3, the driving of the first pump 911 and the second pump 912 starts at time T0. Thus, the first solvent and the second solvent start to be supplied to the analysis flow path. Thereafter, from time T1 to time T2, the sample filled in the sample loop connected by the switching valve in the automatic sampler 920 is introduced into the analysis flow path. The sample is introduced into the column 931 in a state diluted by the mixed solution of the first solvent and the second solvent introduced into the second mixer 913D via the tube 914.

[0066] When the introduction of the sample is completed at time T2, the mixed solution of the first solvent and the second solvent is supplied to the analysis flow path as the mobile phase. Figure 4 In the example, the flow rate ratio of the first solvent and the second solvent after time T2 is constant, but in reality, the flow rate ratio of the first solvent and the second solvent after time T2 may vary based on the setting used in the analysis of the sample (setting according to the gradient elution method).

[0067] ( Figure 5 : Dilution introduction method)

[0068] Figure 5 The structural example includes a first mixer 913G and a second mixer 913D. Figure 5 The analytical flow path also includes a first pump 911, a second pump 912, a third pump 990, tubes 821, 822, 823, 824, 825, 826, an automatic sampler 920, and a column oven 930. The column oven 930 includes a column 931. The third pump 990 supplies a solvent (dilution solvent) for diluting a sample to the analytical flow path.

[0069] exist Figure 5 In the structural example of , the first solvent supplied from the first pump 911 is introduced into the first mixer 913G via the tube 821. The second solvent supplied from the second pump 912 is introduced into the first mixer 913G via the tube 822. The first solvent and the second solvent are mixed in the first mixer 913G and then introduced into the column 931 via the tubes 823, 824, and 826.

[0070] The sample injected from the autosampler 920 is introduced into the second mixer 913D via the tube 824. The third pump 990 supplies the dilution solvent to the second mixer 913D via the tube 825. The sample is diluted in the second mixer 913D and then introduced into the column 931 via the tube 826.

[0071] exist Figure 5 Attachment N4 for explaining the liquid delivery form in the dilution mode is shown in FIG. Attachment N4 includes a graph showing the liquid delivery form to the analysis flow path (tubes 821 to 826) before and after the sample is injected from the autosampler 920. In the graph, the vertical axis schematically represents the flow rate, and the horizontal axis represents time.

[0072] As shown in the graph of note N4, the driving of the first pump 911 and the second pump 912 starts at time T0. This starts the supply of the first solvent and the second solvent to the analysis channel.

[0073] Then, from time T1 to time T2, the sample is introduced from the autosampler 920 into the second mixer 913D while the flow rates of the first pump 911 and the second pump 912 are reduced. From time T1 to time T2, the third pump 990 is driven to introduce the dilution solvent into the second mixer 913D. After being diluted in the second mixer 913D, the sample is introduced into the column 931 through the tube 826.

[0074] When the introduction of the sample is completed at time T2, the driving of the third pump 990 is stopped, and the flow rates of the first pump 911 and the second pump 912 are restored to the flow rates before the reduction. Thus, the mixed liquid of the first solvent and the second solvent is supplied to the analysis flow path as the mobile phase. Figure 5 In the example, the flow rate ratio of the first solvent and the second solvent after time T2 is constant, but in reality, the flow rate ratio of the first solvent and the second solvent after time T2 may vary based on the setting used in the analysis of the sample (setting according to the gradient elution method).

[0075] ( Figure 6 : Sample solution introduction method)

[0076] Figure 6 The structural example includes a first mixer 913G and a second mixer 913D. Figure 6 The analytical flow path also includes a first pump 911, a second pump 912, a third pump 990, tubes 831, 832, 833, 834, 835, 836, an automatic sampler 920, and a column oven 930. The column oven 930 includes a column 931. The third pump 990 supplies a solvent (dilution solvent) for diluting a sample to the analytical flow path.

[0077] exist Figure 6 In the structural example of , the first solvent supplied from the first pump 911 is introduced into the first mixer 913G via the tube 831. The second solvent supplied from the second pump 912 is introduced into the first mixer 913G via the tube 832. The first solvent and the second solvent are mixed in the first mixer 913G and then introduced into the column 931 via the tube 833 and the tube 836.

[0078] The sample injected from the automatic sampler 920 is diluted by the dilution solvent supplied from the third pump 990 via the tube 834 , and is introduced into the column 931 through the second mixer 913D and the tube 836 .

[0079] exist Figure 6Attachment N5 for explaining the liquid delivery form in the dilution mode is shown in FIG. Attachment N5 includes a graph showing the liquid delivery form to the analysis flow path (tubes 831 to 836) before and after the sample is injected from the autosampler 920. In the graph, the vertical axis schematically represents the flow rate, and the horizontal axis represents time.

[0080] As shown in the graph of note N5, the driving of the first pump 911 and the second pump 912 starts at time T0. This starts the supply of the first solvent and the second solvent to the analysis channel.

[0081] Thereafter, from time T1 to time T2, the pump 990 is driven while the flow rates of the first pump 911 and the second pump 912 are reduced, thereby introducing the sample from the automatic sampler 920 into the second mixer 913D. Thus, the sample is introduced into the column 931 after being diluted by the first solvent from the first pump 911 and the second solvent from the second pump 912. In addition, during the period from time T1 to time T2, the ratio of the first solvent to the second solvent may be the same ratio as that at time T0, or may be set to another ratio. That is, the ratio is not particularly limited as long as it is a ratio that can appropriately introduce the sample from the automatic sampler 920 into the second mixer 913D.

[0082] When the introduction of the sample is completed at time T2, the driving of the third pump 990 is stopped, and the driving of the first pump 911 and the second pump 912 is restarted. Thus, the mixed liquid of the first solvent and the second solvent is supplied to the analysis flow path as a mobile phase. Figure 6 In the example, the flow rate ratio of the first solvent and the second solvent after time T2 is constant, but in reality, the flow rate ratio of the first solvent and the second solvent after time T2 may vary based on the setting used in the analysis of the sample (setting according to the gradient elution method).

[0083] ( Figure 7 : High-pressure gradient dilution method)

[0084] Figure 7 The structural example includes a mixer 913X. Figure 7 The column oven 930 also includes a first pump 911, a second pump 912, tubes 841, 842, 843, 844, an automatic sample injector 920, and a column oven 930. The column oven 930 includes a column 931.

[0085] exist Figure 7 In the configuration example, the first solvent supplied from the first pump 911 is introduced into the mixer 913X via the tube 841. The second solvent supplied from the second pump 912 is introduced into the mixer 913X via the tube 842 and the tube 843. The first solvent and the second solvent are mixed in the mixer 913X and then introduced into the column 931 via the tube 844.

[0086] The sample injected from the autosampler 920 is introduced into the mixer 913X via the tube 843. The sample is diluted with the first solvent in the mixer 913X and then introduced into the column 931 via the tube 844.

[0087] exist Figure 7 , which is used to explain the liquid delivery form in the dilution mode. Note N6 includes a graph showing the liquid delivery form to the analysis flow path (tubes 841 to 844) before and after the sample is injected from the automatic sampler 920. In the graph, the vertical axis schematically represents the flow rate, and the horizontal axis represents time.

[0088] As shown in the graph of note N6, the driving of the first pump 911 and the second pump 912 starts at time T0. This starts the supply of the first solvent and the second solvent to the analysis channel.

[0089] Thereafter, from time T1 to time T2, the sample is introduced into the mixer 913X from the automatic sampler 920. Thus, the sample is diluted with the first solvent in the mixer 913X and then introduced into the column 931.

[0090] When the introduction of the sample is completed at time T2, the second solvent is introduced into the mixer 913X. Thus, the mixed solution of the first solvent and the second solvent is supplied to the analysis flow path as a mobile phase. Figure 7 In the example, the flow rate ratio of the first solvent and the second solvent after time T2 is constant, but in reality, the flow rate ratio of the first solvent and the second solvent after time T2 may vary based on the setting used in the analysis of the sample (setting according to the gradient elution method).

[0091] [Comparison with the structure according to the prior art]

[0092] So far the main reference Figure 2 and Figure 3 The structure of the embodiment of the present disclosure is described. Figures 4 to 7 Here, the structure of the embodiment of the present disclosure is described by comparison with the structure according to the prior art.

[0093] Figure 8 This is a diagram showing evaluations on five criteria for the structure of this embodiment and the structure according to the prior art. The five points are as follows.

[0094] (1) Change of dilution ratio

[0095] (2) Import costs

[0096] (3) Changes in the dilution mixer

[0097] (4) Changes in the gradient mixer

[0098] (5) Performance of standard injection

[0099] exist Figure 8 In the analysis, the results are expressed as grades A to C. Grade A means that the structure is suitable for analysis with respect to the benchmark. Grade B means that the structure is not suitable for analysis with respect to the benchmark. Grade C means that the structure is not suitable for analysis with respect to the benchmark. The following describes the contents and results of the benchmark.

[0100] (1) Change of dilution ratio

[0101] The criterion "change of dilution ratio" means whether the dilution ratio of the sample can be changed in the dilution mode.

[0102] In bypass mode ( Figure 4 ), the dilution ratio is based on the ratio of the diameter of the bypass line (tube 814) for introducing the first solvent and the second solvent into the second mixer 913D to the diameter of the tube 815 for introducing the sample into the second mixer 913D. Figure 4 ), the ratio of the diameters of tube 814 and tube 815 is fixed. Therefore, in the bypass mode, the dilution ratio of the sample is fixed and cannot be changed. Therefore, the bypass mode is assigned a level C in terms of the criterion "change of the dilution ratio".

[0103] Dilution introduction method ( Figure 5 ) and sample solution introduction method ( Figure 6 ) can change the dilution ratio of the sample by adjusting the flow rate of the third pump 990. In addition, the high pressure gradient dilution method ( Figure 7 ) The dilution ratio of the sample can be changed by adjusting the flow rate of the first pump 911. Therefore, the diluent introduction method, the sample solution introduction method, and the high-pressure gradient dilution method are given a level A with respect to the criterion "change of dilution ratio".

[0104] In this embodiment, the dilution mode is as follows Figure 3 As shown. Figure 3 In the illustrated configuration, the LC system 100 can change the dilution ratio of the sample by adjusting the flow rate of the first pump 11. Therefore, the configuration of the present embodiment is assigned a rank A with respect to the criterion "change of dilution ratio".

[0105] (2) Import costs

[0106] The second criterion "introduction cost" means that the increase in cost can be suppressed in the implementation of the LC system.

[0107] With bypass mode ( Figure 4 ), high pressure gradient dilution method ( Figure 7 ), the structure of this embodiment ( Figure 2 and Figure 3 ) compared to the diluent introduction method ( Figure 5) and sample solution introduction method ( Figure 6 ) requires a third pump (3rd pump 990).

[0108] Therefore, in terms of the baseline "introduction cost", the bypass method ( Figure 4 ), high pressure gradient dilution method ( Figure 7 ) and the structure of this embodiment are given grade A. On the other hand, the dilution liquid introduction method ( Figure 5 ) and sample solution introduction method ( Figure 6 ) is assigned a grade of C.

[0109] In addition, in the structure of this embodiment, it is necessary to use Figure 2 ) and dilution position ( Figure 3 ) between the elements of the analysis flow path 50. However, as shown in Fig. 9 and Fig.10 As described above, such elements can be realized by using a flow path switching valve. The flow path switching valve does not require an expensive drive unit like a pump. Therefore, even if it is necessary to use a flow path switching valve in a standard position ( Figure 2 ) and dilution position ( Figure 3 ) between the elements of the analysis flow path 50, the structure of this embodiment is also assigned level A in terms of the benchmark "introduction cost".

[0110] (3) Changes in the dilution mixer

[0111] The reference "change of the mixer for dilution" means that the mixer used for dilution of the sample in the dilution mode can be changed.

[0112] exist Figures 4 to 6 In any of the structures, the second mixer 913D can be detached from the analysis flow path and can therefore be replaced. Figure 7 In the structure of , the mixer 913X can be detached from the analysis flow path and can therefore be replaced. Figures 4 to 7 In any of the structures, the mixer used for diluting the sample in the dilution mode can be changed.

[0113] However, in Figures 4 to 7 In the structure of, when each structure is used in the standard mode, the sample must pass through the mixer used for dilution of the sample in the dilution mode. Figures 4 to 7 In the structure, the change (replacement) of the above mixer will affect the analytical performance in the standard mode.

[0114] On the other hand, such an influence does not occur in the structure of the present embodiment. That is, in the structure of the present embodiment, both the first mixer 13G and the second mixer 13D can be detached from the analysis flow path 50 and can therefore be replaced. Figure 2 As described above, the sample introduced from the autosampler 20 does not need to pass through the mixer (second mixer 13D) used for diluting the sample in the dilution mode. Therefore, in the configuration of this embodiment, changing (exchanging) the second mixer 13D does not affect the analytical performance in the standard mode.

[0115] Based on the above, the criterion "Changes in dilution mixer" is the same as Figures 4 to 7 Unlike the structure of the embodiment which is assigned level B, the structure of this embodiment is assigned level A.

[0116] (4) Changes in the gradient mixer

[0117] The reference "change of the mixer for gradient" means that the mixer used for mixing the first solvent and the second solvent according to the gradient elution method can be changed in the standard mode.

[0118] exist Figures 4 to 7 In the structure of the embodiment and the structure of the present embodiment, the mixer can be detached from the analysis flow path. Figures 4 to 7 In the configuration of and the configuration of this embodiment, the mixer used for mixing the first solvent and the second solvent according to the gradient elution method can be changed in the standard mode.

[0119] but, Figure 7 The mixer 913X of the structure (high pressure gradient dilution method) is used to mix the first solvent and the second solvent and also to dilute the sample. Figure 7 In the structure of , the mixer for mixing the first solvent and the second solvent cannot be changed independently of the mixer for diluting the sample.

[0120] Therefore, regarding the standard "change of the gradient mixer", Figures 4 to 6 The structure of the embodiment and the structure of the present embodiment are given a grade of A, but Figure 7 The structure is given a grade of B.

[0121] (5) Performance of standard injection

[0122] The benchmark "Performance of standard injection" means how good the analysis performance is in standard mode.

[0123] Bypass mode( Figure 4 ) is not suitable for analysis in the standard mode. The reason is that as long as the bypass line (tube 814) is connected to the second mixer 913D, a part of the sample from the automatic sampler 920 is transported to the tube 813 through the tube 814 when it is introduced into the second mixer 913D, and then merges with the tube 815 again and returns to the tube 814. Therefore, the performance of the benchmark "standard injection" is not suitable. Figure 4 The structure is given a grade of C.

[0124] Dilution introduction method ( Figure 5 ) is not suitable for analysis in standard mode. More specifically, in the diluent introduction method ( Figure 5 ), it can be said that the analysis in the standard mode can be performed by stopping the third pump 990. However, the sample passes through the second mixer 913D before reaching the column 931. Therefore, the sample is adversely affected by passing through the second mixer 913D. Therefore, the standard injection performance is Figure 5 The structure is given a grade of B.

[0125] Sample solution introduction method ( Figure 6 ) is not suitable for analysis in the standard mode. The reason is that when the third pump 990 is driven to transport the sample from the autosampler 920 to the column 931, the sample and the dilution solvent supplied from the third pump 990 are mixed in the second mixer 913D, whereby the sample is diluted by the dilution solvent. Therefore, the performance of the standard injection is not suitable for the standard mode. Figure 6 The structure is given a grade of C.

[0126] High pressure gradient dilution method ( Figure 7 ) is not suitable for analysis in the standard mode. The reason is that when the second pump 912 is driven to transport the sample from the autosampler 920 to the column 931, the sample and the second solvent supplied from the second pump 912 are mixed in the second mixer 913D, whereby the sample is diluted by the second solvent. Therefore, the performance of the standard injection is not suitable for the standard mode. Figure 7 The structure is given a grade of C.

[0127] On the other hand, in the structure of this embodiment, as shown in FIG. Figure 2 As described, in the analysis in the standard mode, the sample from the autosampler 20 reaches the column 31 without passing through the mixer. Therefore, the structure of this embodiment is given a grade A in terms of the criterion "performance of standard injection".

[0128] As reference Figure 8 As described above, for at least one of the five criteria shown in (1) to (5), Figures 4 to 7 The structure of is given an evaluation other than rank A. On the other hand, the structure of this embodiment is given an evaluation of rank A with respect to all the five criteria shown in (1) to (5) above.

[0129] In particular, with respect to the benchmark shown in (5) (benchmark "performance of standard injection"), Figures 4 to 7 Unlike all structures of the embodiment that are given evaluations other than rank A, the structure of this embodiment is given an evaluation of rank A.

[0130] [Specific example of the structure of the liquid supply unit]

[0131] Fig. 9 1 is a diagram showing an example of a specific structure of the liquid supply unit 13. Fig. 9 In the example, the liquid delivery unit 13 includes a first mixer 13G, a second mixer 13D and a flow switching valve 600. The flow switching valve 600 is implemented, for example, using a flow switching valve manufactured by Shimadzu Corporation (https: / / www.an.shimadzu.co.jp / hplc / prominence / modules / 7_flow-changeover-valve.htm). The flow switching valve 600 has six ports 601 to 606. Ports 601 to 606 can be connected to another adjacent port respectively. Port 606 is a port that stops the flow. The flow switching valve 600 switches the flow in the analysis flow path 50 by changing the group of connected ports among the multiple ports. In this way, the switching of the flow in the analysis flow path 50 can be achieved in a space-saving manner.

[0132] The first mixer 13G has three openings. The first opening is connected to the first pump 11 via a tube 131 . The second opening is connected to the port 602 via a tube 1302 . The third opening is connected to the port 605 via a tube 1305 .

[0133] The second mixer 13D has three openings. The first opening is connected to the second pump 12 via a tube 132 . The second opening is connected to the port 601 via a tube 1301 . The third opening is connected to the automatic sampler 20 via a tube 134 .

[0134] Fig.10 601 to 606 of the flow path switching valve 600 in the standard position. Fig.10 As shown, in the standard position, port 601 is connected to port 602, port 603 is connected to port 604, and port 605 is connected to port 606.

[0135] exist Figure 2 In the process, the first solvent passes through tube 133. Figure 2 The tube 133 uses Fig.10 This is achieved by the tube 1302, the port 602, the port 601 and the tube 1301. Figure 2 In the process, the sample passes through tube 135. Figure 2 The tube 135 is used Fig.10 This is achieved by tube 1304, port 604, port 603 and tube 1303.

[0136] The first solvent passes through the tube 131 , the second solvent passes through the tube 132 , and the mixed liquid of the first solvent and the second solvent passes through the tube 134 .

[0137] Fig.11 1 is a diagram showing an example of the connection form of the ports 601 to 606 of the dilution position of the flow path switching valve 600 .

[0138] like Fig.11 As shown, in the dilution position, port 601 is connected to port 606 , port 603 is connected to port 602 , and port 605 is connected to port 604 .

[0139] exist Figure 3 In the process, the sample passes through tube 135. Figure 3 The tube 135 is used Fig.11 This is achieved by tube 1304, port 604, port 605 and tube 1305.

[0140] exist Figure 3 In the process, the sample diluted with the first solvent (sample+first solvent) passes through tube 136. Figure 3 The tube 136 uses Fig.11 The first solvent passes through the tube 131, and the second solvent passes through the tube 132 and the tube 134.

[0141] [Processing flow]

[0142] Fig.12 is a flow chart of the process performed by the LC system 100 to analyze a sample. Fig.12 The processing is realized by the processor 61 of the controller 60 executing a given program.

[0143] In step S10 , the LC system 100 reads the setting of the analysis mode. In one embodiment, for example, the user operates the input device to register the analysis mode in the storage device 62 . The input device registers the analysis mode in the storage device 62 via the interface 63 .

[0144] In step S12, the LC system 100 determines whether the read analysis mode is the standard mode or the dilution mode. If the LC system 100 determines that it is the standard mode, it advances the control to step S14, and if it determines that it is the dilution mode, it advances the control to step S16.

[0145] In step S14, the LC system 100 controls the state of the liquid delivery unit 13 to the standard position ( Figure 2 In one embodiment, in step S14, the controller 60 controls the connection states of the ports 601 to 606 of the flow path switching valve 600 to Fig.10 Status shown.

[0146] In step S16, the LC system 100 controls the state of the liquid delivery unit 13 to the dilution position ( Figure 3In one embodiment, in step S16, the controller 60 controls the connection states of the ports 601 to 606 of the flow path switching valve 600 to Fig.11 Status shown.

[0147] In step S18, the LC system 100 starts driving the first pump 11 and the second pump 12 to start the mobile phase flowing into the analytical flow path 50. The control of step S18 is similar to that of step S20. Figure 2 The period from time T0 to time T1 in the above description corresponds to the period from time T0 to time T1.

[0148] In step S20, the LC system 100 causes the autosampler 20 to inject the sample into the analysis flow path 50. The control of step S20 is similar to Figure 2 The period from time T1 to time T2 in the above description corresponds to the period from time T1 to time T2.

[0149] In step S22, the LC system 100 analyzes the sample. The control of step S22 is Figure 2 In one embodiment, the controller 60 obtains the detection signal based on the components of the sample separated in the column 31 from the detector 40 and processes it, thereby realizing the analysis. Fig.12 The processing is finished.

[0150] [Technical solution]

[0151] Those skilled in the art will appreciate that the above-mentioned multiple exemplary embodiments are specific examples of the following technical solutions.

[0152] (Item 1) The liquid delivery unit of a technical solution may be a liquid delivery unit that delivers the first solution and the second solution as mobile phases to a column of a liquid chromatography analysis system. Alternatively, the first solution may be supplied from a first pump. Alternatively, the second solution may be supplied from a second pump. Alternatively, the liquid chromatography analysis system may include an injection portion for injecting a sample. Alternatively, the liquid delivery unit may include: a first mixer; a second mixer; and a switching device that switches the flow path from the first pump and the second pump to the column between the first flow path and the second flow path. Alternatively, the first flow path and the second flow path may include the first mixer and the second mixer, respectively. Alternatively, in the first flow path, the first mixer may be located upstream of the injection portion, and the second mixer may be located downstream of the injection portion. Alternatively, in the second flow path, both the first mixer and the second mixer may be located upstream of the injection portion. The switching device may configure the first flow path as the flow path in a first mode for diluting the sample before introducing the sample into the column, and configure the second flow path as the flow path in a second mode for not diluting the sample before introducing the sample into the column.

[0153] By using the liquid delivery unit described in the first item, in a mode in which the sample is diluted before being introduced into the column, the sample injected from the injection portion can be diluted in the second mixer. On the other hand, in a mode in which the sample is not diluted before being introduced into the column, the sample can reach the column without passing through both the first mixer and the second mixer. Thus, the liquid chromatography analysis system is suitable not only for analysis in a mode in which the sample is diluted before being introduced into the column, but also for analysis in a mode in which the sample is not diluted before being introduced into the column.

[0154] (Item 2) The liquid delivery unit described in Item 1 may further include a controller for controlling the state of the switching device. Alternatively, the controller controls the state of the switching device to form the first flow path in the first mode and controls the state of the switching device to form the second flow path in the second mode.

[0155] According to the liquid delivery unit described in the second aspect, since the state of the switching device is controlled by the controller, the burden of switching the state of the switching device on the operator of the liquid chromatography analysis system can be reduced.

[0156] (Item 3) In the liquid supply unit described in Item 1 or Item 2, at least one of the first mixer and the second mixer may be attachable to and detachable from the flow path.

[0157] With the liquid feeding unit described in Item 3, at least one of the first mixer and the second mixer can be replaced.

[0158] (Item 4) In the liquid feeding unit described in Item 3, the first mixer and the second mixer may have mixing capacities different from each other.

[0159] According to the liquid feeding unit described in Item 4, the ability to mix solutions can be made different between the first mixer and the second mixer according to the desire of the user of the liquid chromatography analysis system.

[0160] (Item 5) In the liquid delivery unit described in any one of Items 1 to 4, the switching device may include a flow path switching valve.

[0161] By adopting the liquid delivery unit described in Item 5, the switching device can be realized in a space-saving manner.

[0162] (Item 6) It may be that a liquid chromatography analysis system of a technical solution is a liquid chromatography analysis system that uses a first solution and a second solution as mobile phases, wherein the liquid chromatography analysis system includes: a column; a first pump that supplies the first solution; a second pump that supplies the second solution; an injector that injects a sample toward the column; a first mixer; a second mixer; and a switching device that switches the flow path from the first pump and the second pump to the column between a first flow path and a second flow path, wherein the first flow path and the second flow path respectively include the first mixer and the second mixer. The second mixer, in the first flow path, the first mixer is located at a position upstream of an injection portion where the injector injects the sample, and the second mixer is located downstream of the injection portion. In the second flow path, both the first mixer and the second mixer are located upstream of the injection portion. The switching device configures the first flow path as the flow path in a first mode where the sample is diluted before being introduced into the column, and configures the second flow path as the flow path in a second mode where the sample is not diluted before being introduced into the column.

[0163] According to the liquid chromatography analysis system described in Item 6, in a mode in which the sample is diluted before being introduced into the column, the sample injected from the injection portion can be diluted in the second mixer. On the other hand, in a mode in which the sample is not diluted before being introduced into the column, the sample can reach the column without passing through both the first mixer and the second mixer. Thus, the liquid chromatography analysis system is suitable not only for analysis in a mode in which the sample is diluted before being introduced into the column, but also for analysis in a mode in which the sample is not diluted before being introduced into the column.

[0164] (Item 7) The liquid chromatography analysis system described in Item 6 may further include a controller for controlling the state of the switching device. Alternatively, the controller may control the state of the switching device to form the first flow path in the first mode and control the state of the switching device to form the second flow path in the second mode.

[0165] According to the liquid chromatography analysis system described in Item 7, since the state of the switching device is controlled by the controller, the burden of switching the state of the switching device on the operator of the liquid chromatography analysis system can be reduced.

[0166] (Item 8) In the liquid chromatography analysis system described in Item 6 or 7, at least one of the first mixer and the second mixer may be detachable from the flow path.

[0167] In the liquid chromatography analysis system described in Item 8, at least one of the first mixer and the second mixer is replaceable.

[0168] (Item 9) In the liquid chromatography analysis system described in Item 8, the first mixer and the second mixer may have mixing capacities different from each other.

[0169] According to the liquid chromatography analysis system described in Item 9, the performance of the solution mixture can be made different between the first mixer and the second mixer according to the desire of the user of the liquid chromatography analysis system.

[0170] (Item 10) In the liquid chromatography analysis system described in any one of Items 6 to 9, the switching device may include a flow path switching valve.

[0171] By adopting the liquid chromatography analysis system recorded in Item 10, the switching device can be realized in a space-saving manner.

[0172] (Item 11) A control method of a technical solution is a control method of a liquid chromatography analysis system that uses a first solution and a second solution as mobile phases and is executed by a computer, wherein the control method includes the following steps: obtaining an analysis mode; and controlling the flow path from a first pump that supplies the first solution and a second pump that supplies the second solution to a column of the liquid chromatography analysis system according to the analysis mode.

[0173] Alternatively, the liquid chromatography analysis system includes an injection portion for sample injection, a first mixer, and a second mixer, and the step of controlling the flow path includes the following steps: when the analysis mode is a first mode in which the sample is diluted before being introduced into the column, the flow path is controlled so that the first mixer is located upstream of the injection portion and the second mixer is located downstream of the injection portion; and when the analysis mode is a second mode in which the sample is not diluted before being introduced into the column, the flow path is controlled so that both the first mixer and the second mixer are located upstream of the injection portion.

[0174] According to the control method described in Item 11, in a mode in which the sample is diluted before being introduced into the column, the sample injected from the injection portion can be diluted in the second mixer. On the other hand, in a mode in which the sample is not diluted before being introduced into the column, the sample can reach the column without passing through both the first mixer and the second mixer. Thus, the liquid chromatography analysis system is suitable not only for analysis in a mode in which the sample is diluted before being introduced into the column, but also for analysis in a mode in which the sample is not diluted before being introduced into the column.

[0175] The embodiments disclosed herein are illustrative in all aspects and are not restrictive. The scope of the present disclosure is indicated by the claims rather than the description of the embodiments described above, and the scope of the present disclosure is intended to include all modifications within the meaning and scope equivalent to the claims.

Claims

1. A liquid delivery unit that delivers a first solution and a second solution as mobile phases to a column of a liquid chromatography analysis system, wherein: supplying the first solution from a first pump, supplying the second solution from a second pump, The liquid chromatography analysis system comprises an injection part for injecting samples, The liquid delivery unit comprises: The first mixer; a second mixer; and a switching device for switching the flow path from the first pump and the second pump to the column between the first flow path and the second flow path, The first flow path includes the first mixer and the second mixer, and the second flow path includes the first mixer and the second mixer, In the first flow path, the first mixer is located upstream of the injection portion, and the second mixer is located downstream of the injection portion. In the second flow path, the first mixer and the second mixer are both located upstream of the injection portion. The switching device, in a first mode for diluting the sample before introducing the sample into the column, configures the first flow path as the flow path from the first pump and the second pump to the column, In the second mode in which the sample is not diluted before being introduced into the column, the second flow path is configured as a flow path from the first pump and the second pump to the column.

2. The liquid delivery unit according to claim 1, wherein: The liquid delivery unit also includes a controller for controlling the state of the switching device. The controller controls the state of the switching device in the first mode to form the first flow path, In the second mode, the state of the switching device is controlled so as to form the second flow path.

3. The liquid delivery unit according to claim 1 or 2, wherein: At least one of the first mixer and the second mixer is attachable to and detachable from the flow path from the first pump and the second pump to the column.

4. The liquid delivery unit according to claim 1 or 2, wherein: The first mixer and the second mixer have mixing capacities different from each other.

5. The liquid delivery unit according to claim 1 or 2, wherein: The switching device includes a flow path switching valve.

6. A liquid chromatography analysis system, which uses a first solution and a second solution as mobile phases, wherein: The liquid chromatography analysis system includes: column; a first pump that supplies the first solution; a second pump for supplying the second solution; an injector that injects a sample toward the column; The first mixer; a second mixer; and a switching device for switching the flow path from the first pump and the second pump to the column between the first flow path and the second flow path, The first flow path includes the first mixer and the second mixer, and the second flow path includes the first mixer and the second mixer, In the first flow path, the first mixer is located upstream of an injection portion of the injector into which a sample is injected, and the second mixer is located downstream of the injection portion. In the second flow path, the first mixer and the second mixer are both located upstream of the injection portion. The switching device, in a first mode for diluting the sample before introducing the sample into the column, configures the first flow path as the flow path from the first pump and the second pump to the column, In the second mode in which the sample is not diluted before being introduced into the column, the second flow path is configured as a flow path from the first pump and the second pump to the column.

7. The liquid chromatography analysis system according to claim 6, wherein: The liquid chromatography analysis system also includes a controller for controlling the state of the switching device. The controller controls the state of the switching device in the first mode to form the first flow path, In the second mode, the state of the switching device is controlled so as to form the second flow path.

8. The liquid chromatography analysis system according to claim 6 or 7, wherein: At least one of the first mixer and the second mixer is attachable to and detachable from the flow path from the first pump and the second pump to the column.

9. The liquid chromatography analysis system according to claim 6 or 7, wherein: The first mixer and the second mixer have mixing capacities different from each other.

10. The liquid chromatography analysis system according to claim 6 or 7, wherein: The switching device includes a flow path switching valve.

11. A control method for a liquid chromatography analysis system, which is executed by a computer, wherein the liquid chromatography analysis system uses a first solution and a second solution as mobile phases, wherein: The control method comprises the following steps: Obtaining analytical patterns; and controlling a flow path from a first pump for supplying the first solution and a second pump for supplying the second solution to a column of the liquid chromatography analysis system according to the analysis mode, The liquid chromatography analysis system comprises an injection portion for injecting a sample, a first mixer and a second mixer. The step of controlling the flow path comprises the following steps: When the analysis mode is a first mode in which the sample is diluted before being introduced into the column, the flow path is controlled so that the first mixer is located upstream of the injection portion and the second mixer is located downstream of the injection portion; When the analysis mode is a second mode in which the sample is not diluted before being introduced into the column, the flow path is controlled so that both the first mixer and the second mixer are located upstream of the injection portion.

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