JP2010060335A - Multi-dimensional gas chromatograph apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multi-dimensional gas chromatograph apparatus capable of easily switching between a switching analysis and a single column analysis using a second detector. <P>SOLUTION: The chromatograph apparatus includes: a first column 13 for separating components in a sample introduced from a sample introduction part 11; a first detector 17 for detecting the sample separated by the first column 13; a second detector 23 for detecting the sample separated by a second column 18; and a passage switching part 14 for switching the passage so as to send the sample passing through the first column 13 to either the first detector 17 or the second column 18. The chromatograph apparatus further includes a second sample introduction part 20 and a third column 21 for separating components in a sample introduced from the sample introduction part 20 and is configured so that the sample separated in the third column 21 is detected by the second detector 23. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a multidimensional gas chromatograph apparatus.

  In fields such as environmental analysis, petrochemical analysis, and fragrance analysis, it is necessary to separate each component in a sample with a complex composition containing many kinds of trace components and perform quantitative analysis with high sensitivity. In many cases, a tomographic (GC) apparatus cannot completely separate peaks of a plurality of components and cannot perform sufficient analysis. In such a case, a multi-dimensional gas chromatograph apparatus (hereinafter sometimes abbreviated as multi-dimensional GC) in which a plurality of columns are combined is very useful.

  For example, in the multi-dimensional GC described in Patent Document 1, the flow path after separating the sample components by flowing the sample gas vaporized in the sample vaporization chamber to the first column is first detected via the flow path switching unit. Branching into the detector side, the second column and the second detector side, and usually the sample gas flowing out from the first column is introduced into the first detector to detect the sample components. The sample gas is selectively introduced to the second column side at the timing when the sample gas containing a component that cannot be sufficiently separated passes, and the separation characteristics are improved through the second column and then introduced to the second detector for detection. I do.

JP 2006-226679 A

  In the multi-dimensional GC as described above, it is general to use different types of detectors as the first detector and the second detector, respectively. In this case, a general-purpose detector such as FID (Flame Ionization Detector) or TCD (Thermal Conductivity Detector) is used as the first detector, and the second detector A mass spectrometer with high sensitivity and high qualitative ability is often used as the instrument. In the multi-dimensional GC configured as described above, when it is desired to perform single column analysis using the second detector as a detector, the first column connected to the flow path switching unit after the operation of the apparatus is stopped. Had to be removed and reconnected to the second detector.

  However, such work is complicated and there is a problem that it takes time until the analysis can be performed stably after the operation of the apparatus is resumed. In particular, in a system using a mass spectrometer as the second detector, it is necessary to lower the temperature of the mass spectrometer and open the vacuum in order to change the column connection as described above. For this reason, it takes several hours to half a day before the vacuum connection is made again after the column connection is changed and stable analysis data can be obtained.

  The present invention has been made to solve such a problem, and the object of the present invention is to switch between switching analysis and single column analysis using the second detector by simply and quickly. It is to provide a multi-dimensional GC.

A multi-dimensional gas chromatograph apparatus according to the present invention, which has been made to solve the above problems, includes a first column for separating components in a sample introduced from a sample introduction unit, a second column, and the first column. A first detector for detecting the sample separated by the second column; a second detector for detecting the sample separated by the second column; and the sample passed through the first column for the first detector or the second In a multidimensional gas chromatograph apparatus comprising a flow path switching means for switching a flow path so as to selectively flow to any of the columns,
a) a second sample introduction unit provided separately from the sample introduction unit;
b) a third column for separating components in the sample introduced from the second sample introduction part;
And the sample separated by the third column is detected by the second detector.

  As described above, the multidimensional gas chromatograph apparatus according to the present invention has a sample introduction unit (hereinafter referred to as a first sample introduction unit or a first sample introduction unit) for introducing a sample into the first column. ) In addition to a second sample introduction part (hereinafter sometimes referred to as a second sample introduction part) for introducing a sample into the third column, and further separating by the second column. In addition to the sample, the sample separated by the third column is detected by the second detector. In such a configuration, when a sample is introduced from the first sample introduction unit, the sample is separated by the first column and reaches the flow path switching means and is detected by the first detector, or the second It is further separated by the column and then detected by the second detector. On the other hand, when a sample is introduced from the second sample introduction part, the sample is separated by the third column and detected by the second detector without passing through the flow path switching means. Therefore, switching analysis and single column analysis using the second detector can be switched and executed depending on which sample introduction part the sample is introduced from.

  As described above, according to the multidimensional gas chromatograph apparatus of the present invention, switching analysis and single column analysis using the second detector can be easily and quickly switched without changing the column connection. Can be executed.

  Hereinafter, an embodiment of a multi-dimensional GC according to the present invention will be described with reference to the drawings. FIG. 1 is an overall configuration diagram of a multi-dimensional GC according to the present embodiment.

  In the multidimensional GC of the present embodiment, the first sample introduction unit 11 is connected to the inlet end of the first column 13 disposed in the first column oven 12. The outlet end of the first column 13 is connected to a flow path switching unit 14 and is branched into a first branch pipe 15 and a second branch pipe 16 by the flow path switching unit 14. The end of the first branch pipe 15 is connected to the first detector 17 made of FID, and the end of the second branch pipe 16 is connected to the inlet end of the second column 18 disposed in the second column oven 19. Yes. The outlet end of the second column 18 is connected to a second detector 23 comprising a mass spectrometer via an interface unit 22. The channel switching unit 14 is, for example, a Deans-type channel switching unit, and the sample gas that has passed through the first column 13 is changed by switching the channel of the makeup gas in accordance with an instruction from the analysis control unit 32 described later. It flows alternatively to the first branch pipe 15 and the second branch pipe 16. At this time, the same makeup gas as the carrier gas flows through the other branch pipe. In addition, the thing of the structure which this applicant proposes in Unexamined-Japanese-Patent No. 2006-64646 can also be utilized as the flow-path switching part 14. FIG.

  The second column oven 19 is further provided with a second sample introduction unit 20, and the second sample introduction unit 20 is connected to the inlet end of the third column 21 disposed in the second column oven 19. Has been. The third column 21 is the same type of column as the first column 13, and its outlet end is connected to the second detector 23 via the interface unit 22.

  FIG. 2 is an enlarged exploded sectional view showing the configuration of the interface unit 22. The interface unit 22 is provided with a sample introduction tube 41 for introducing a sample into the ionization chamber of the second detector 23 (that is, a mass spectrometer), and the second column 18 and the third column are provided in the sample introduction tube 41. 21 outlet ends (or inert tubes and resistance tubes connected to them) are connected. At this time, each of the columns 18 and 21 is inserted into two through holes provided in a ferrule 42 made of resin or the like, and a nut 43 accommodating the ferrule 42 is screwed to the tip of the sample introduction tube 41. Thereby, the sample introduction tube 41 and the second column 18 and the third column 21 are connected in an airtight manner.

  The first sample introduction unit 11 and the second sample introduction unit 20 are each provided with a sample vaporization chamber for vaporizing the injected liquid sample, and a carrier gas (He gas or the like) having a predetermined flow rate is provided in the sample vaporization chamber. Through the first column 13 and the third column 21.

  The detection signals from the first detector 17 and the second detector 23 are both sent to the data processing unit 31, and the data processing unit 31 creates a chromatogram and executes predetermined quantitative analysis and qualitative analysis processing. The analysis control unit 32 controls the operation of each unit based on a comprehensive instruction from the central control unit 33. For example, the flow path switching unit 14, the sample introduction units 11, 20, the detectors 17, 23, In addition, the temperature and / or pressure of the column ovens 12 and 19 are monitored by the analysis control unit 32, and the operation of each unit is controlled so as to have a predetermined value (for the sake of simplicity, the analysis control unit 32 is shown in the figure). (Some of the signal lines from are omitted.) Further, the central control unit 33 also controls the data processing unit 31 and receives processing results such as chromatograms from the data processing unit 31 and displays them on the display unit 35. Connected to the central control unit 33 are an input unit 34 for performing various input settings including analysis conditions and a display unit 35 for displaying analysis conditions, analysis results, and the like. The substance of the central control unit 33 and the data processing unit 31 is a general-purpose personal computer, and various controls and processes are achieved by operating predetermined control / processing programs installed in the computer. In addition to the keyboard, the input unit 34 includes a mouse as a pointing device.

  Next, an example of the operation of the multi-dimensional GC will be described.

  In the multi-dimensional GC according to the present embodiment, when a sample is injected into the first sample introduction unit 11 by a microsyringe or the like, the sample is immediately vaporized in the sample vaporization chamber and rides on the carrier gas flow to the first. Introduced into the column 13. The first column 13 is heated to an appropriate temperature by the first column oven 12, and each component in the sample gas is temporally separated while passing through the first column 13. Thereafter, each sample component reaching the outlet end of the first column 13 is sent to either the first branch pipe 15 or the second branch pipe 16 by the action of the flow path switching unit 14. Here, when the sample components are sent to the first branch pipe 15, the respective components are sequentially detected by the first detector 17, and when they are sent to the second branch pipe 16, they are introduced into the second column 18. Is done. The second column 18 is heated to an appropriate temperature by the second column oven 19, and the sample components are further separated in the process of passing through the second column 18 and sequentially detected by the second detector 23.

  On the other hand, when a sample is injected into the second sample introduction unit 20, the sample vaporized in the sample vaporization chamber is introduced into the third column 21 along the carrier gas flow. The third column 21 is heated to an appropriate temperature by the second column oven 19, and each component in the sample gas is temporally separated in the process of passing through the third column 21 and reaches the second detector 23. Are detected sequentially.

  Therefore, in the multidimensional GC of the present embodiment, if a sample is injected into the first sample introduction unit 11, single column analysis by the combination of the first column 13 and the first detector 17, or the first column 13, the first column Switching analysis can be performed by a combination of the detector 17, the second column 18, and the second detector 23. If a sample is injected into the second sample introduction unit 20, the combination of the third column 21 and the second detector 23. It will be possible to perform single column analysis.

  Therefore, according to the multidimensional GC according to the present embodiment, for example, when routinely analyzing a large number of samples, the sample is usually injected into the second sample introduction unit 20 and the third column 21 and the second detection are performed. The same sample is introduced from the first sample introduction unit 11 only when the peak (for example, insufficiently separated peak) that is desired to be analyzed in detail is recognized. For example, switching analysis using a column may be performed. The first column and the second column may be the same type of column, for example, both polar columns may be used, or columns having different separation characteristics, for example, a polar column and a nonpolar column may be used. In either case, sample components that have been insufficiently separated in the first column can be subjected to separation by the second column, and the degree of separation can be increased in detection by the second detector. Here, since the second detector 23 is a mass spectrometer, according to the multidimensional GC of the present embodiment, high sensitivity and qualitative capability can be obtained in both single column analysis and switching analysis without changing the column connection. Analysis using a high mass spectrometer can be performed.

  In the multi-dimensional GC according to the present embodiment, an example in which regular gasoline is analyzed as a sample is shown. Nonpolar columns (60 m × 0.32 mm ID df. 5.0 μm, 100% dimethylpolysiloxane) are used as the first column 13 and the third column 21, and polar columns (30 m × 0.32 ID df.0.25) are used as the second column 18. μm, polyethylene glycol). The temperature setting of the first column oven 12 is 100.0 ° C. → 10 ° C./min→250° C., and the temperature setting of the second column oven 19 is 50 ° C. The first detector 17 is FID and the set temperature is 310 ° C., and the second detector 23 is MS and the set temperature of the ion source is 200 ° C.

  FIG. 3 shows a total ion chromatogram obtained by analyzing regular gasoline by single column analysis using a combination of the second sample introduction unit 20, the third column 21, and the second detector 23. The user determines a peak to be further analyzed with reference to the output of the second detector 23 by such single column analysis.

  For example, assume that the peak indicated by the arrow in the chromatogram of FIG. 3 is to be analyzed in more detail. The user injects the same sample into the first sample introduction unit 11 this time, performs analysis by the first column 13 and the first detector 17 without performing switching, and sets the timing at which the target peak elutes from the first column 13. Identify (this is called monitoring analysis). The chromatogram obtained at this time is shown in FIG. As described above, the third column 21 and the first column 13 are the same type of column. Here, the “same kind of column” means a column of the same diameter and the same length filled with the same stationary phase, regardless of whether it is a capillary column or a packed column. Therefore, the chromatogram obtained by this monitoring analysis shows a separation pattern similar to the chromatogram of the single column analysis using the third column 21 (FIG. 3) (however, depending on the lot difference between the columns and the difference in usage history). There will be some variation in retention time). As a result, the user can easily specify which peak on the chromatogram of the monitoring analysis corresponds to the target peak.

  A user creates a time program (switching program) for switching analysis by referring to the chromatogram obtained by the monitoring analysis on the display unit 35 and performing a predetermined operation on the input unit 34. For example, in the case of the chromatogram of FIG. 4, the component eluting from the first column 13 (that is, the fraction shown by shading in FIG. 5) is sent to the second column 18 between 7.6 and 7.8 minutes. Create a switching program.

  Thereafter, the same sample is again injected into the first sample introduction unit 11, and analysis according to the above switching program is executed. As a result, the flow path switching unit 14 is controlled according to the switching program, and only the fraction indicated by the hatching in FIG. 5 among the sample components sequentially eluted from the first column 13 is introduced into the second column 18. FIG. 6 shows the output of the second detector 23 in such switching analysis as a mass chromatogram. From this result, it can be seen that the fraction that appeared to be a single component in the chromatograms of FIGS. 3 and 4 is composed of two linear hydrocarbons and one cyclic hydrocarbon.

  In the present embodiment, the second sample introduction unit 20 and the third column 21 are provided on the second column oven 19 side, but these may be provided on the first column oven 12 side. Alternatively, a third column oven may be newly provided, and the second sample introduction unit 20 and the third column 21 may be provided there. Furthermore, in this embodiment, the same type as the first column 13 is used as the third column 21, but a different type of column may be used. The column type can be selected regardless of whether it is a capillary column or a packed column, and the stationary phase can be appropriately selected by those skilled in the art from nonpolar, low polarity, medium polarity and high polarity. Further, the first detector 17 and the second detector 23 are not limited to the FID and the mass spectrometer, respectively, but are gas chromatographs such as an electron capture detector, a flame photometric detector, and a flame thermonic detector. Various devices that can be used as detectors can be applied.

1 is an overall configuration diagram of a multi-dimensional GC according to an embodiment of the present invention. FIG. 3 is an exploded cross-sectional view illustrating a configuration of an interface unit in the multi-dimensional GC according to the embodiment. The figure which shows the chromatogram acquired by the single column analysis which used the 3rd column in the multidimensional GC of the embodiment. The figure which shows the chromatogram acquired by the monitoring analysis which used the 1st column in the multidimensional GC of the embodiment. The enlarged view of the chromatogram of FIG. The figure which shows the structural formula corresponding to the mass chromatogram obtained by the switching analysis by the multidimensional GC of the embodiment, and each peak.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... 1st sample introduction part 12 ... 1st column oven 13 ... 1st column 15 ... 1st branch pipe 16 ... 2nd branch pipe 17 ... 1st detector 18 ... 2nd column 19 ... 2nd column oven 20 ... 1st 2 Sample introduction part 21 ... 3rd column 22 ... Interface part 23 ... 2nd detector 31 ... Data processing part 32 ... Analysis control part 33 ... Central control part 34 ... Input part 35 ... Display part 41 ... Sample introduction pipe 42 ... Ferrule 43 ... Nut

Claims (2)

The first column for separating the components in the sample introduced from the sample introduction unit, the second column, the first detector for detecting the sample separated by the first column, and the second column. A second detector for detecting the sample, and a flow path switching means for switching the flow path so that the sample that has passed through the first column flows selectively to either the first detector or the second column, In the multi-dimensional gas chromatograph apparatus provided,
a) a second sample introduction unit provided separately from the sample introduction unit;
b) a third column for separating components in the sample introduced from the second sample introduction part;
The multidimensional gas chromatograph is characterized in that the sample separated by the third column is detected by the second detector.   The multidimensional gas chromatograph according to claim 1, wherein the first column and the third column are the same type of column.

Images