Mass spectrometry data processing device

Abstract

To provide a technique by which a peak associated with ions derived from a reagent added to a specimen can be easily recognized on mass spectrum.SOLUTION: A mass spectrometry data processing device (40) comprises: a memory unit (41) which stores information to identify a reagent and information corresponding to the mass-to-charge ratio of ions generated from the reagent; a display unit (60); a mass spectrum data entry reception unit (42); a reagent information entry reception unit (45) for receiving the entry of the reagent specific information about the reagent added to a specimen; a peak identification unit (46) for identifying a peak associated with the ions generated from the reagent by matching the entry reagent specific information with the information stored in the memory unit; and a display processing unit (47), which creates a mass spectrum from the mass spectrum data to display on the display unit, for displaying the peak identified by the peak identification unit and other peaks in a recognizable form.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a mass spectrometry data processing device.

Background Art

[0002] One of the devices for qualitatively and quantitatively analyzing metabolites contained in a biological sample is a gas chromatograph mass spectrometer. When analyzing metabolites using a gas chromatograph mass spectrometer, derivatization (TMSylation) is often performed to add a trimethylsilyl group (Si(CH3)3) to the metabolites in the sample to enhance the volatility of the metabolites. Then, after vaporizing the sample containing the TMSylated metabolites in the sample vaporization chamber of the gas chromatograph, it is separated by a column, introduced into a mass spectrometer for ionization, and mass spectrometry is performed (for example, Patent Document 1).

[0003] When qualitatively analyzing metabolites contained in a sample using a mass spectrometer, scan measurement is performed to obtain a mass spectrum, which is compared with the mass spectra of known compounds recorded in a compound database. Then, the metabolites are qualitatively analyzed based on the similarity of the two mass spectra. When quantitatively analyzing metabolites contained in a sample, SIM measurement or MRM measurement is performed. In SIM measurement and MRM measurement, target ions are determined in advance for each metabolite to be measured, and a calibration curve is created from the area value or intensity value of the peak of the target ions obtained by measuring a standard sample. Then, the metabolites are quantified by comparing the area value or intensity value of the peak of the target ions obtained by measuring an actual sample with the calibration curve.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] When a sample is derivatized, ions derived from the derivatizing reagent are generated in addition to the ions derived from the metabolite when ionizing with a mass spectrometer. Therefore, in the mass spectrum of the metabolite, not only the peaks of the ions derived from the metabolite but also the peaks of the ions derived from the derivatizing reagent appear.

[0006] When qualitatively analyzing the metabolites contained in a sample, when comparing the mass spectrum obtained by measuring the sample with the mass spectra of known compounds recorded in a compound database, multiple candidate compounds with high similarity may be extracted. If the analyst is proficient in metabolite analysis, they can exclude the ions derived from the derivatizing reagent and select an appropriate compound from the similarity of the mass distributions of the other ions to qualitatively analyze the metabolite. However, if the analyst is inexperienced in metabolite analysis, there is a possibility of misidentification by qualitatively analyzing based on the similarity of the mass distribution of the ions derived from the derivatizing reagent.

[0007] Also, for the target ions used in SIM measurement or MRM measurement of metabolites, a scan measurement is performed to obtain a mass spectrum, and the ions measured with high intensity are determined as the target ions. Also in this case, if the analyst is inexperienced in metabolite analysis, they may not know that the ions are derived from the derivatizing reagent and may determine those ions as the target ions. If the ions derived from the derivatizing reagent are used as the target ions in SIM measurement or MRM measurement, another metabolite derivatized in the same way as the target metabolite or a compound derived from a reagent or the like may be erroneously detected, and the target metabolite cannot be correctly qualitatively and quantitatively analyzed.

[0008] Here, the case of using a derivatizing reagent to enhance the volatility of metabolites in a gas chromatograph was taken as an example for explanation, but there are the same problems as above in various situations where a sample added with a reagent is mass-analyzed, such as when using a reagent to enhance the ionization efficiency in a mass spectrometer.

[0009] The problem to be solved by the present invention is to provide a technique that can easily recognize peaks related to ions derived from a reagent included in a mass spectrum obtained by mass spectrometry of a sample to which the reagent has been added, regardless of the proficiency of the analyst.

Means for Solving the Problem

[0010] The mass spectrometry data processing apparatus according to the present invention made to solve the above problems includes: a storage unit that stores reagent identification information for identifying a reagent and information associating the mass-to-charge ratio of ions generated from the reagent; a display unit; a mass spectrum data input reception unit that receives an input of mass spectrum data obtained by mass spectrometry of a sample; a reagent information input reception unit that receives an input of reagent identification information of the reagent added to the sample in the mass spectrometry; a peak identification unit that collates the reagent identification information input to the reagent information input reception unit with the information stored in the storage unit and identifies peaks related to ions generated from the reagent among the peaks included in the mass spectrum data; a display processing unit that creates a mass spectrum from the mass spectrum data input to the mass spectrum data input reception unit and displays it on the display unit, and displays the peaks identified by the peak identification unit in a form distinguishable from other peaks and includes.

Advantages of the Invention

[0011] In the mass spectrometry data processing apparatus according to the present invention, when an analyst inputs mass spectrum data obtained by mass spectrometry of a sample and inputs reagent identification information for identifying the reagent added to the sample, a mass spectrum is created from the mass spectrum data, and peaks related to ions derived from the reagent are displayed in a form distinguishable from other peaks. Therefore, regardless of the proficiency of the user, peaks related to ions derived from the reagent included in the mass spectrum can be easily recognized.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Mode for Carrying Out the Invention

[0013] An embodiment of the mass spectrometry data processing apparatus according to the present invention will be described below with reference to the drawings.

[0014] FIG. 1 shows the main configuration of the gas chromatograph mass spectrometry system 1 of this embodiment. The gas chromatograph mass spectrometry system 1 includes a gas chromatograph unit 10 that separates compounds contained in a sample, and a mass spectrometry unit that performs mass spectrometry on the compounds separated by the gas chromatograph unit.

[0015]

[0016] The gas chromatograph unit includes a sample vaporization chamber 11, a carrier gas flow path 12, a microsyringe 13, a column 14, and a column oven 15. A carrier gas flow path 12 is connected to the sample vaporization chamber 11, and a carrier gas such as helium supplied from a gas source (not shown) is supplied to the sample vaporization chamber 11 through the carrier gas flow path 12. The sample introduced from the microsyringe 13 is vaporized in the sample vaporization chamber 11 and introduced into the column 14 along with the flow of the carrier gas. The column 14 is temperature-controlled to a predetermined temperature by the column oven 15, and the compounds in the sample are separated while flowing through the column 14. In this embodiment, the microsyringe 13 is used as the sample introduction unit, but other units may be used to introduce the sample.

[0017] The mass spectrometry unit includes a vacuum chamber 21 that is evacuated to a predetermined degree of vacuum by a vacuum pump (not shown). Inside the vacuum chamber 21, an ion source 22, an ion lens 23, a quadrupole mass filter 24, and an ion detector 25 are arranged. The compounds separated by the column 14 of the gas chromatograph unit are sequentially ionized by the ion source 22, the flight direction is converged by the ion lens 23, mass-separated by the quadrupole mass filter 24, and detected by the ion detector 25. An electron ionization source or a chemical ionization source is used for the ion source 22.

[0018] The control and processing unit 40 includes a storage unit 41. In the storage unit 41, a reagent database 411 that records information on derivatization reagents (reagent name, reagent ID, molecular formula, molecular structure, etc.) described later and information associating the mass-to-charge ratio and structural formula of the ions generated from the reagent is stored. The storage unit 41 also stores a compound database (library) 412 that records information on various known compounds (compound name, molecular formula, molecular structure, retention time, mass spectrum, calibration curve, etc.). Here, the reagent database 411 and the compound database 412 are stored in the storage unit 41, but a database that can be used via a network such as the Internet may be used.

[0019] The control and processing unit 40 includes, as functional blocks, a mass spectrum data input reception unit 42, a measurement control unit 43, a compound information input reception unit 44, a reagent information input reception unit 45, a peak identification unit 46, and a display processing unit 47. The entity of the control and processing unit 40 is, for example, a general personal computer, and each of the above functional blocks is realized by executing a mass spectrometry data processing program installed in advance by a processor. Further, an input unit 50 and a display unit 60 are connected to the control and processing unit 40.

[0020] Next, the flow of analysis using the gas chromatograph mass spectrometry system 1 of the present embodiment will be described with reference to the flowchart of FIG. 2. Here, an example of determining target ions used when qualitatively and quantitatively analyzing metabolites contained in a sample will be described.

[0021] When quantifying metabolites contained in a sample, SIM measurement or MRM measurement is performed. When using a mass spectrometry unit having one mass filter as in the present embodiment, SIM measurement is performed. When using a so-called tandem type mass spectrometry unit having a front-stage mass filter and a rear-stage mass filter, MRM measurement can also be performed. In SIM measurement, target ions are determined in advance for each metabolite to be measured, and a calibration curve is created from the area value or intensity value of the peak obtained by measuring a standard sample. Then, the area value or intensity value of the peak of the target ions obtained by the measurement is quantified with reference to the calibration curve. In SIM measurement (similarly in MRM measurement) of metabolites, scan measurement is performed to obtain a mass spectrum, and target ions are determined from the ions detected therein.

[0022] When the user instructs the start of analysis, first, the mass spectrum data input reception unit 42 determines the mass spectrum data to be used for analysis.

[0023] The measurement data will be described. Metabolites contained in a biological sample often have low volatility and are difficult to vaporize in the sample vaporization chamber 11 of the gas chromatograph section. Therefore, when measuring such metabolites, pretreatment is performed to enhance volatility using various derivatization reagents. As such pretreatment, for example, a treatment is performed to enhance the volatility of metabolites by performing derivatization (TMSylation) that adds a trimethylsilyl group (Si(CH3)3) to the metabolites in the sample. Also in this example, the metabolites contained in the sample are TMSylated and measured.

[0024] The measurement data is acquired by the measurement control unit 43 operating the gas chromatograph mass spectrometer section 10 as follows. When a sample after pretreatment is set in the microsyringe 13 and an instruction to start measurement is given, the measurement control unit 43 feeds a carrier gas at a predetermined flow rate to the sample vaporization chamber 11 through the carrier gas flow path 12, and injects a predetermined amount of the sample from the microsyringe 13 into the sample vaporization chamber 11. The sample injected into the sample vaporization chamber 11 is vaporized in the sample vaporization chamber 11 and then introduced into the column 14 along with the flow of the carrier gas. In the column 14, the compounds contained in the sample gas are separated from each other.

[0025] The sample separated by the column 14 is sequentially ionized by the ion source 22 of the mass spectrometer section, the flight path is converged by the ion lens 23, and then enters the quadrupole mass filter 24. A predetermined voltage for scanning the mass-to-charge ratio of the ions to be passed is applied to the quadrupole mass filter 24, and ions having a mass-to-charge ratio corresponding to the voltage applied at each time point pass through the quadrupole mass filter 24 and are detected by the ion detector 25. The output signal from the ion detector 25 is sequentially stored in the storage unit 41.

[0026] When the measurement is completed, the mass spectrum data input reception unit 42 reads out the output signal from the ion detector 25 stored in the storage unit 41 and creates a total ion current chromatogram (TICC) (step 1). The TICC is the sum of the intensity values in the mass-to-charge ratio direction in the three-dimensional data representing the intensity values with respect to the two axes of time and mass-to-charge ratio acquired by the above measurement.

[0027] When the user reads out the data created as described above, displays the TICC on the screen of the display unit 60, and designates the peak appearing in the TICC, the mass spectrum data input reception unit 42 displays on the screen of the display unit 60 the mass spectrum acquired in the time zone corresponding to the designated peak (step 2). Further, the spectrum data is collated with the mass spectra of various compounds recorded in the compound database 412 stored in the storage unit 41, and the compound names and the mass spectra of the said compounds are displayed on the screen of the display unit 60 in a predetermined number in descending order of similarity (step 3). Note that the similarity of the mass spectra is calculated based on the position and intensity of the peaks, and since the specific processing thereof is conventionally known, detailed description thereof is omitted here.

[0028] The user checks the predetermined number of compound names and the mass spectra of the said compounds displayed on the screen of the display unit 60, confirms that the metabolite to be measured is included therein, and selects the said metabolite. The mass spectrum data input reception unit 42 receives the input of the metabolite by the user and determines it as the target of subsequent processing. Further, the mass spectrum data created from the measurement data of the sample and used in the above collation is determined as the target of subsequent processing (step 4).

[0029] As described above, by confirming that the mass spectrum corresponding to the peak of the TICC acquired by measurement corresponds to the metabolite to be measured, it is ensured that the mass spectrum used for subsequent analysis correctly measures the metabolite to be measured. When the measurement target is a metabolite derived from a living body or requires pretreatment as in the present embodiment, peaks of another compound similar to the metabolite to be measured or another compound generated during pretreatment may appear in the TICC. If the user erroneously selects these peaks and uses the corresponding mass spectra for subsequent analysis, the target ions of compounds that are not the metabolite to be measured will be determined. Therefore, in the present embodiment, the similarity with the mass spectra recorded in the compound database 412 is confirmed as described above.

[0030] When the user selects a metabolite to be measured from among a predetermined number of compounds displayed on the screen of the display unit 60, the compound information input reception unit 44 acquires (inputs) information (information including at least the compound name and molecular weight) of the selected metabolite (compound) from the compound database 412 (step 5).

[0031] Subsequently, the reagent information input reception unit 45 causes the user to input information on the derivatization reagent (TMS in this example) used in the measurement for which the mass spectrum data was acquired (step 6). This input can be performed, for example, by the reagent information input reception unit 45 displaying a list of reagents recorded in the reagent database 411 stored in the storage unit 41 on the screen of the display unit 60 and causing the user to select the reagent used during the measurement from among them. When multiple reagents are used, the user is made to input information on all the reagents used. Also, when the reagent used by the user during the measurement is not recorded in the reagent database 411 stored in the storage unit 41, the user is made to input information on the derivatization reagent (reagent name, reagent ID, molecular formula, molecular structure, etc.) and the mass-to-charge ratio of the ions generated from the reagent. The input reagent information is added to the reagent database 411.

[0032] When the reagent information is input, the peak identification unit 46 reads out information on the input reagent from the reagent database 411. Then, the mass-to-charge ratio of the peaks included in the mass spectrum data is compared with the mass-to-charge ratio of the ions generated from the reagent, and the matching ones are identified (step 7).

[0033] When the peak is identified by the peak identification unit 46, the display processing unit 47 creates a mass spectrum for screen display from the mass spectrum data, and displays, on the screen of the display unit 60 in a form distinguishable from other peaks, the peaks identified by the peak identification unit 46 among the peaks on the mass spectrum (step 8). The analyst refers to the mass spectrum displayed on the display unit 60 and determines the target ions in the SIM measurement (step 9).

[0034] Figures 3 to 7 are examples of the display of the mass spectrum by the display processing unit 47. This mass spectrum was obtained by subjecting 2-Aminoethanol derivatized with TMS to gas chromatography-mass spectrometry. The upper right part of the mass spectra in Figures 3 to 7 shows the structure of the molecule with two TMS groups added to 2-Aminoethano. In the following, the display examples in Figures 3 to 7 will be individually described, but it is also possible to adopt a display form that combines a plurality of these.

[0035] In the example of Figure 3, among the peaks on the mass spectrum, the values of the mass-to-charge ratios displayed above the peaks of the ions (m / z = 73, 147) derived from TMS are marked with circles and highlighted. This drawing is in monochrome, but appropriate coloring may be performed when highlighting (the same applies to Figures 4 to 7 below). By adopting such a display form, even those who are not familiar with the analysis can easily identify the peaks of the ions derived from TMS and determine the ions corresponding to the other peaks as target ions in the SIM measurement.

[0036] In the example of Figure 4, among the peaks on the mass spectrum, the peaks of the ions (m / z = 73, 147) derived from TMS are highlighted with thick lines. With this display form as well, the peaks of the ions derived from TMS can be easily identified, and the ions corresponding to the other peaks can be determined as target ions in the SIM measurement.

[0037] In the example of Figure 5, among the peaks on the mass spectrum, the peaks of the ions (m / z = 73, 147) derived from TMS are displayed with thin dashed lines so as not to be conspicuous. In this display form, the peaks other than the ions derived from TMS are displayed conspicuously, so the ions corresponding to any of those peaks can be determined as target ions in the SIM measurement.

[0038] The example in Fig. 6 shows the structural formulas of the ions (m / z = 73, 147) derived from TMS above the peaks of the ions on the mass spectrum. With this display form, similar to the above, the peaks of the ions derived from TMS can be easily identified, and furthermore, it is possible to grasp which part of TMS the ions constitute.

[0039] The example in Fig. 7 shows that among the peaks on the mass spectrum, a diamond mark and a rectangle mark are respectively attached to the peak of the ion with the largest mass-to-charge ratio and the value of the mass-to-charge ratio displayed above the peak of the ion with the second largest mass-to-charge ratio.

[0040] In gas chromatography-mass spectrometry as in this embodiment, usually, the molecular ion of the derivatized compound appears as the peak of the ion having the largest mass-to-charge ratio on the mass spectrum. Therefore, in the example shown in Fig. 7, it can be easily grasped that the ion with m / z = 205 marked with a diamond is the molecular ion. Also, in the case of the mass spectrum obtained by measuring the compound subjected to the pretreatment of TMS as in this embodiment, the ion having the second largest mass-to-charge ratio is the one from which a methyl group has been removed from the above molecular ion. In the example shown in Fig. 7, it is m / z = 190, and the difference in mass-to-charge ratio from the molecular ion corresponds to 15 of the methyl group. These ions with large mass-to-charge ratios are the molecular ions themselves or the ions with little fragmentation of the molecular ions, and have more structural information than the fragment ions that are fragments of the molecular ions, and have higher discriminability than the fragment ions. Therefore, the analyst can perform highly accurate and discriminable quantification by using the ions highlighted in this way as the target ions in the SIM measurement. Note that the specification of these peaks may be configured to be performed by the above peak specification unit 46.

[0041] In addition, in the example shown in FIG. 7, the peak identification unit 46 may be configured to perform a check of the mass-to-charge ratio for the ion with the maximum mass-to-charge ratio. Specifically, in the example of FIG. 7, the molecular weight of the original compound 2-Aminoethanol is 61, the molecular weight of TMS is 73, and since two TMS groups are added, by performing the calculation 61 + 73×2 - 2 = 205, it can be understood that the peak of the ion having the maximum mass-to-charge ratio is the one with two TMS groups added to 2-Aminoethanol. Note that the "-2" in the above formula is the atomic weight of the two hydrogen atoms (H) replaced by TMS.

[0042] Here, the case of determining the target ion in SIM measurement has been described, but the same configuration may be applied when determining the target ion in MRM measurement. Specifically, the information of the precursor ion and product ion derived from the reagent is stored in the storage unit 41, and in the mass spectrum displayed when selecting the precursor ion in the MS / MS scan measurement, those that match the above information may be displayed so as to be distinguishable from other peaks.

[0043] In addition, the same configuration can be preferably used when identifying the compounds contained in the sample. When identifying the compounds contained in the sample, when comparing the mass spectrum obtained by measuring the sample with the mass spectra of known compounds recorded in the compound database 412 in the same manner as in the above embodiment, a plurality of candidate compounds with close similarity may be extracted. If the analyst is an expert, the peaks derived from the reagent can be excluded, and an appropriate compound can be selected from the similarity of the other peaks. However, if the analyst is inexperienced in the analysis, there is a possibility of selecting and misidentifying a compound based on the similarity of the peaks of the ions derived from the reagent.

[0044] On the one hand, in this embodiment, since the peaks of reagent-derived ions are displayed discriminably from other ions, the priority of candidate compounds with high similarity of the peaks of reagent-derived ions is lowered, the priority of candidate compounds with high similarity of other peaks is increased, or other indicators (such as retention indicators) are referred to, etc., so that appropriate compounds can be selected and correctly identified.

[0045] The above embodiment is an example and can be appropriately modified in accordance with the gist of the present invention.

[0046] In the above embodiment, after inputting the mass spectrum data obtained by measurement and the information of the compound, the information of the reagent is input, but this order may be reversed. That is, after inputting the information of the reagent, the mass spectrum data and the information of the compound may be input. Further, in the above embodiment, in order to perform an operation to confirm that the ion with the maximum mass-to-charge ratio is the molecular ion, the information of the compound is input, but if this operation is not necessary, only the information of the reagent may be input.

[0047] The above embodiment combines a gas chromatograph and a single quadrupole type mass spectrometer, but it may also be combined with a gas chromatograph and a mass spectrometer with other configurations (such as tandem quadrupole type, time-of-flight type, etc.). Further, a liquid chromatograph may be used instead of the gas chromatograph. Furthermore, even when only a mass spectrometer is used without using a chromatograph, the same configuration as above can be adopted.

[0048] In the above embodiment, the case where TMS is used as a derivatization reagent to enhance the volatility of the metabolite to be measured is described, but the same configuration as above can be adopted when other types of derivatization reagents are used. Also, when a reagent is used for purposes other than enhancing volatility, such as when a reagent is used to increase the ionization efficiency in a mass spectrometer, the same configuration as above can be adopted.

[0049] [Aspect] It is obvious to those skilled in the art that the above-described exemplary embodiments are specific examples of the following aspects.

[0050] (Item 1) A mass spectrometry data processing apparatus according to an aspect of the present invention includes: a storage unit that stores information associating reagent identification information for identifying a reagent with the mass-to-charge ratio of ions generated from the reagent; a display unit; a mass spectrometry data input reception unit that receives an input of mass spectrometry data obtained by mass-analyzing a sample; a reagent information input reception unit that receives an input of reagent identification information of a reagent added to the sample in the mass spectrometry; a peak identification unit that collates the reagent identification information input to the reagent information input reception unit with the information stored in the storage unit, and identifies peaks related to ions generated from the reagent among the peaks included in the mass spectrometry data; a display processing unit that creates a mass spectrum from the mass spectrometry data input to the mass spectrometry data input reception unit and displays the mass spectrum on the display unit, and displays the peaks identified by the peak identification unit in a form distinguishable from other peaks and includes.

[0051] In the mass spectrometry data processing apparatus according to Item 1, when an analyst inputs mass spectrometry data obtained by mass-analyzing a sample and inputs reagent identification information for identifying a reagent added to the sample, a mass spectrum is created from the mass spectrometry data, and peaks related to ions derived from the reagent are displayed in a form distinguishable from other peaks. Therefore, regardless of the proficiency of the user, peaks related to ions derived from the reagent included in the mass spectrum can be easily recognized.

[0052] (Item 2) The mass spectrometry data processing apparatus according to Item 2 is the mass spectrometry data processing apparatus according to Item 1, wherein the display processing unit draws the peaks identified by the peak identification unit and other peaks with lines of different thicknesses and / or colors.

[0053] In the mass spectrometry data processing device according to the second aspect, peaks related to ions derived from a reagent can be visually recognized from the widths and colors of the peaks on the mass spectrum displayed on the screen of the display unit. For example, by displaying the peaks of ions derived from the reagent thickly or in a conspicuous color, the analyst can be prompted not to select such peaks as target ions in SIM measurement or MRM measurement. Conversely, by displaying the peaks of ions derived from the reagent thinly or in an inconspicuous color, other peaks can be made more conspicuous, and the analyst can be prompted to select target ions from among them. Also, when identifying a compound by comparing the mass spectrum data with the mass spectrum data recorded in the compound database, the priority of candidate compounds with a high similarity of peaks of ions derived from the reagent is lowered, and the priority of candidate compounds with a high similarity of other peaks is increased. By referring to other indicators (such as retention indicators), an appropriate compound can be selected and correctly identified.

[0054] (Article 3) The mass spectrometry data processing device according to the third aspect is the mass spectrometry data processing device according to the first or second aspect, wherein the display processing unit displays the mass-to-charge ratio of the peak near the peak on the mass spectrum, and displays the mass-to-charge ratio of the peak identified by the peak identification unit so as to be distinguishable from other peaks.

[0055] According to the mass spectrometry data processing device according to the third aspect, peaks related to ions derived from a reagent can be grasped together with the information on their mass-to-charge ratios.

[0056] (Article 4) The mass spectrometry data processing device according to the fourth aspect is the mass spectrometry data processing device according to any one of the first to third aspects, wherein the display processing unit emphasizes and displays the peak having the largest mass-to-charge ratio among the peaks appearing in the mass spectrum, and / or its mass-to-charge ratio.

[0057] For example, in the case of a mass spectrum obtained by gas chromatography-mass spectrometry, usually, the molecular ion becomes the ion having the largest mass-to-charge ratio. In the mass spectrometry data processing device according to Item 4, by highlighting the peak of this ion and its mass-to-charge ratio, the molecular ion can be presented to the analyst as a candidate for the target ion in SIM measurement or MRM measurement. Also, when quantifying a compound, by emphasizing the degree of coincidence of the peak of the molecular ion having the largest mass-to-charge ratio, the compound can be correctly identified.

[0058] (Item 5) The mass spectrometry data processing device according to Item 5 is the mass spectrometry data processing device according to Item 4, and further, a compound information input reception unit that receives an input of information on the mass-to-charge ratio of the compound contained in the sample is provided, The peak identification unit obtains the mass-to-charge ratio of the ion generated by the reaction of the compound and the reagent by using the mass-to-charge ratio of the ion generated from the reagent corresponding to the reagent identification information received by the reagent information input reception unit and the information on the mass-to-charge ratio of the compound.

[0059] According to the mass spectrometry data processing device according to Item 5, it is possible to collate the mass-to-charge ratio calculated by the peak identification unit with the information on the mass-to-charge ratio of the ion corresponding to the peak highlighted by the display processing unit.

[0060] (Item 6) The mass spectrometry data processing device according to Item 6 is the mass spectrometry data processing device according to Item 4 or Item 5, and the reagent performs derivatization to add a trimethylsilyl group to the compound contained in the sample, the display processing unit further highlights and displays the peak having the second largest mass-to-charge ratio among the peaks appearing in the mass spectrum and / or its mass-to-charge ratio.

[0061] In the mass spectrum obtained by measuring a compound that has undergone a pretreatment of derivatization (TMSylation) to add a trimethylsilyl group, the peak with the second largest mass-to-charge ratio is one in which a methyl group has been removed from the molecular ion generated by the reaction of the compound and the reagent, and it is a highly discriminative ion having structural information close to that of the molecular ion. In the mass spectrometry data processing apparatus according to Item 6, by highlighting the molecular ion and the ion from which the methyl group has been removed from the molecular ion, these can be presented to the analyst as candidates for target ions in SIM measurement or MRM measurement. Also, when identifying a compound by comparing it with the mass spectrum data recorded in the compound database, the compound can be identified more accurately by attaching importance to the similarity of these ions.

Explanation of Signs

[0062] 1…Gas chromatograph mass spectrometry system 10…Gas chromatograph mass spectrometry unit 11…Sample vaporization chamber 12…Carrier gas flow path 13…Microsyringe 14…Column 15…Column oven 21…Vacuum chamber 22…Ion source 23…Ion lens 24…Quadrupole mass filter 25…Ion detector 40…Control / processing unit 41…Memory unit 411…Reagent database 412…Compound database 42…Mass spectrum data input reception unit 43…Measurement control unit 44…Compound information input reception unit 45…Reagent information input reception unit 46…Peak identification unit 47…Display processing unit 50…Input unit 60…Display unit

Claims

1. A storage unit storing information associating reagent identification information for identifying a reagent with the mass-to-charge ratio of ions generated from the reagent, a display unit, a mass spectrum data input reception unit that receives input of mass spectrum data obtained by mass-analyzing a sample, a reagent information input reception unit that receives input of reagent identification information of a reagent added to the sample in the mass analysis, a peak identification unit that collates the reagent identification information input to the reagent information input reception unit with the information stored in the storage unit and identifies peaks related to ions generated from the reagent among the peaks included in the mass spectrum data, a display processing unit that creates a mass spectrum from the mass spectrum data input to the mass spectrum data input reception unit and displays it on the display unit, and displays the peaks identified by the peak identification unit in a form distinguishable from other peaks A mass spectrometry data processing apparatus comprising.

2. The display processing unit draws the peaks identified by the peak identification unit and other peaks with lines of different thicknesses and / or colors. The mass spectrometry data processing apparatus according to claim 1.

3. The display processing unit displays the mass-to-charge ratio of a peak near the peak on the mass spectrum, and displays the mass-to-charge ratio of the peak identified by the peak identification unit in a distinguishable manner from other peaks. The mass spectrometry data processing apparatus according to claim 1.

4. The display processing unit emphasizes and displays the peak having the largest mass-to-charge ratio among the peaks appearing in the mass spectrum and / or its mass-to-charge ratio. The mass spectrometry data processing apparatus according to claim 1.

5. Furthermore, a compound information input reception unit that receives input of information on the mass-to-charge ratio of a compound contained in the sample is provided, The peak identification unit obtains the mass-to-charge ratio of ions generated by the reaction of the compound and the reagent using the mass-to-charge ratio of ions generated from the reagent corresponding to the reagent identification information received by the reagent information input reception unit and the information on the mass-to-charge ratio of the compound. The mass spectrometry data processing apparatus according to claim 4.

6. The reagent performs derivatization to add a trimethylsilyl group to a compound contained in the sample, The display processing unit further highlights and displays the peak having the second largest mass-to-charge ratio among the peaks appearing in the mass spectrum, and / or its mass-to-charge ratio, in the mass spectrometry data processing apparatus according to claim 4.

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