Mass analysis method and mass analysis device
By generating a theoretical mass spectrum and comparing it with the measured mass spectrum for consistency, peaks other than the components of the analysis and overlapping peaks of homologues are excluded, thus solving the problem of misjudgment in mass spectrometry analysis and achieving higher analysis accuracy and precision.
Patent Information
- Application Number
- CN202080102602.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2020-07-17
- Publication Date
- 2025-09-30
- Estimated Expiration
- 2040-07-17
AI Technical Summary
In mass spectrometry, peaks due to factors other than the target component can lead to misjudgment in qualitative analysis. In particular, when isotopes or homologues are present, the number of mass spectrometric peaks increases, making it difficult to accurately distinguish the peaks of the target component.
By calculating the isotope ratio of the analysis target component, generating a theoretical mass spectrum and comparing its consistency with the measured mass spectrum, the influence of peaks other than the analysis target component is eliminated, the overlapping peaks between homologues are separated, and the mass spectrum interference other than the measurement target is subtracted to ensure the accuracy of the mass spectrum.
It effectively avoids the influence of components other than the analyzed object, improves the accuracy and precision of mass spectrometry analysis, and prevents misjudgment, especially in the presence of isotopes or homologues.
Smart Images
Figure CN115769070B_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to a mass analysis method and a mass analysis device. Background Art
[0002] When analyzing a target substance using a mass spectrometer, it is necessary to distinguish between peaks in the mass spectrum that originate from the target component and peaks that originate from factors other than the target component. In particular, the presence of isotopes or homologues in the target component increases the number of peaks in the mass spectrum. For example, chlorinated paraffin contains numerous components with varying carbon and chlorine numbers, and the resulting mass spectrum can sometimes contain hundreds of peaks.
[0003] Generally, the isotope ratio is known, and a mass spectrum can also produce results reflecting the isotope ratio. Patent Document 1 discloses a technique for qualitative analysis of a sample based on the isotope ratio of the component to be analyzed.
[0004] Prior art literature
[0005] Patent Literature
[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 2010-66036 Summary of the Invention
[0007] Technical problem to be solved by the invention
[0008] However, when there is a peak caused by a factor other than the component to be analyzed, this peak is also considered as an analysis target, which may lead to erroneous determination in qualitative analysis.
[0009] Therefore, the present disclosure provides a technology for easily avoiding the influence of components other than the analysis target component in mass analysis.
[0010] Technical means for solving technical problems
[0011] In order to achieve the above-mentioned purpose, the mass analysis method disclosed in the present invention is a mass analysis method using a mass analysis device, including: through the control unit of the mass analysis device, based on the molecular formula of the analysis object component and the isotope abundance ratio of the element contained in the analysis object component and having multiple isotopes, the mass of the isotopes of the analysis object component and the abundance ratio of the analysis object component of each mass are calculated, thereby calculating a theoretical mass spectrum; through the pretreatment unit of the mass analysis device, the measurement object is ionized; through the mass detection unit of the mass analysis device, the mass of the ionized ions and the number of ions of each mass are detected; through the control unit, a first mass spectrum is calculated based on the detection result of the mass detection unit; the control unit calculates the consistency by comparing the theoretical mass spectrum and the first mass spectrum only for the mass of the peak that exists in the theoretical mass spectrum; and through the control unit, based on the consistency, it is determined whether the analysis object component is present in the measurement object.
[0012] Other features related to the present disclosure are made clear by the description and drawings of this specification. In addition, the present disclosure is achieved and realized by the combination of elements and various elements, the following detailed description and the appended claims.
[0013] The descriptions in this specification are merely typical examples and are not intended to limit the scope of the claims of the present disclosure or the application examples of the present disclosure in any way.
[0014] Effects of the Invention
[0015] According to the technology disclosed in the present invention, it is possible to easily avoid the influence of components other than the analysis target component.
[0016] Problems, structures, and effects other than those described above will become more apparent through the following description of the embodiments. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 This is a functional configuration diagram of the mass spectrometer according to the first embodiment.
[0018] Figure 2 This is a flowchart of the mass analysis method according to the first embodiment.
[0019] Figure 3 This is a diagram showing an example of a theoretical mass spectrum.
[0020] Figure 4 This is a diagram showing an example of a peak in a mass spectrum obtained by measurement.
[0021] Figure 5 This is a flowchart of the mass analysis method of the second embodiment.
[0022] Figure 6 This is a flowchart of the mass analysis method of embodiment 3.
[0023] Figure 7 This is a conceptual diagram of the method of separating ionic strength.
[0024] Figure 8 This is a flowchart of the mass analysis method of embodiment 4. DETAILED DESCRIPTION
[0025] [Implementation Method 1]
[0026] <Example of Mass Spectrometer Configuration>
[0027] Figure 1 This is a functional block diagram of the mass spectrometer 100 according to Embodiment 1. In this embodiment, the mass spectrometer 100 is described as a heating desorption mass spectrometer. A heating desorption mass spectrometer heats the object to be measured (sample) to generate a gas component, ionizes the gas component, and performs mass analysis. Furthermore, mass spectrometers to which the technology disclosed herein can be applied are not limited to heating desorption mass spectrometers; the technology disclosed herein can also be applied to gas chromatography mass spectrometers or liquid chromatography mass spectrometers that separate compounds in the object to be measured using a separation column.
[0028] like Figure 1 As shown, the mass spectrometer 100 includes a heating unit 101 (pre-processing unit), an ionization unit 102 (pre-processing unit), a detection unit 103 (mass detection unit), and a control unit 104 (calculation unit).
[0029] The heating unit 101 heats the object to be measured to generate a gas component. The heating unit 101 can be constituted by, for example, a heating furnace, and the object to be measured can be conveyed to the heating chamber of the heating furnace by an autosampler.
[0030] The ionization section 102 can be composed of a known ionization device and ionizes the gas components generated by the heating section 101. Examples of ionization methods used by the ionization section 102 include atmospheric pressure chemical ionization (APCI), electrospray ionization (ESI), atmospheric pressure photoionization (APPI), and electron ionization (EI). Of these, APCI is less likely to cause structural destruction of the target component (fragmentation of the gas component) during ionization, resulting in less generation of fragmentation peaks. Therefore, the target component can be detected even without separation using chromatography or other methods.
[0031] The detection unit 103 can be composed of a well-known mass analyzer and detects the mass of the ions ionized by the ionization unit 102 and the number of ions of each mass (ion intensity). The detection unit 103 outputs a detection signal of the ion intensity to the control unit 104. Alternatively, the detection unit 103 can output the ion current as a detection signal to the control unit 104.
[0032] The control unit 104 calculates a mass spectrum based on the mass of the ions detected by the detection unit 103 and the number of ions of each mass, and analyzes the object to be measured. In addition, the control unit 104 controls the overall operation of the mass spectrometer 100. For example, the control unit 104 can be composed of a memory that stores a program for operating each part of the mass spectrometer 100, a processor (CPU, MPU, etc.) that executes the program, etc. The control unit 104 can be assembled into a computer terminal such as a personal computer or a smart phone, and the control unit 104 is connected to a storage device for storing various data, an input device for the user to input instructions to the mass spectrometer 100, a display device for displaying the results of the mass analysis or various GUI screens, etc.
[0033] <Quality Analysis Method>
[0034] Figure 2 This is a flowchart showing the mass analysis method according to the first embodiment.
[0035] (Step S1)
[0036] The user of the mass spectrometer 100 determines the component to be analyzed. Specifically, the control unit 104 displays a GUI screen on the display device for the user to determine the component to be analyzed, and the user uses the input device to input the desired component to be analyzed via the GUI screen. Here, data on compounds that may become components to be analyzed can be saved as a database, and the user can select a compound from the database. In addition, the user can also input the chemical formula (molecular formula, structural formula, etc.) of the component to be analyzed. The input information of the component to be analyzed is output to the control unit 104. In this embodiment, the case where the component to be analyzed is chlorinated paraffin is used as an example for explanation.
[0037] (Step S2)
[0038] Based on the molecular formula of the target component and the isotope abundance ratio, control unit 104 calculates the mass and isotope abundance ratio of each isotope to calculate a theoretical mass spectrum. The molecular formulas and isotope abundance ratios of compounds that could be target components can be stored in a database and read by control unit 104, or calculated by control unit 104 based on the chemical formula of the target component input by the user.
[0039] Chlorinated paraffin is an alkane (molecular formula: C n H 2n+1 ) is a general term for compounds that are combined with chlorine. It is a mixture of compounds with different carbon numbers and chlorine numbers. Therefore, if x is the carbon number and y is the chlorine number, the molecular formula of chlorinated paraffin is C x H 2x+2-y Cl y Chlorine 35 Cl and 37There are two stable isotopes of Cl, and their isotope ratio is 35 Cl (75.77%) and 37 Therefore, even if x and y are the same, there are y+1 isotopes with different masses.
[0040] Figure 3 This is a theoretical mass spectrum calculated based on the mass and abundance ratios calculated for x = 14 and y = 5. The horizontal axis represents mass, and the vertical axis represents abundance ratios calculated based on the isotopic abundance ratios of chlorine. The sum of the six peaks is calculated as 1. The theoretical mass spectrum can be calculated by performing the same calculation for all combinations of x and y analyzed.
[0041] (Step S3)
[0042] Return to Figure 2 , the control unit 104 measures the object suspected of containing the target component using the mass spectrometer 100 and obtains a mass spectrum (hereinafter sometimes referred to as the "first mass spectrum"). Specifically, the control unit 104 drives the heating unit 101 and the ionization unit 102 to vaporize and ionize the target component, and receives input of a detection signal from the detection unit 103. The control unit 104 obtains the mass spectrum with mass (mass-to-charge ratio m / z) on the horizontal axis and ion intensity on the vertical axis.
[0043] (Step S4)
[0044] The control unit 104 corrects the mass of the mass spectrum obtained in step S3 based on the ionization reaction in the ionization unit 102. For example, oxygen ions (O2 - ), the control unit 104 shifts the horizontal axis of the acquired mass spectrum to the negative side by 32 Da. That is, the control unit 104 shifts the peak with the horizontal axis of 448 Da to 416 Da.
[0045] (Step S5)
[0046] The control unit 104 calculates the degree of consistency by comparing the theoretical mass spectrum calculated in step S2 with the mass spectrum obtained in step S3. In the calculation of the degree of consistency, the peaks used for comparison are only the masses of the peaks in the theoretical mass spectrum; other peaks are not used for comparison. Therefore, even if there are peaks other than the target component in the mass spectrum obtained in step S3, these peaks can be excluded from the comparison. Here, peaks other than the target component are caused by the mass spectrometer 100 itself, the container of the object to be measured, and impurities other than the target component contained in the object to be measured.
[0047] The theoretical mass spectrum of chlorinated paraffin contains y+1 peaks, but the peaks to be compared are not limited thereto. For example, all peaks may be compared, multiple peaks with relatively high intensities among the peaks in the mass spectrum obtained in step S3 may be compared, or peaks exceeding a predetermined threshold may be compared.
[0048] The method for calculating the degree of coincidence is not particularly limited, but for example, a correlation coefficient can be used.
[0049] Figure 4 This is a diagram showing an example of a peak in a mass spectrum obtained by mass analysis. Figure 4 As shown, each peak in the mass spectrum obtained by the mass analyzer generally has a certain degree of diffusion, rather than a straight line, such as a Gaussian function. Depending on the measurement, this diffusion pattern will change over time, and the position of the peak will shift. This will make the calculated consistency value unstable. Therefore, the control unit 104 calculates the average value of the ion intensity within a range of a predetermined width W on the horizontal axis for the peak of the mass spectrum obtained in step S3, and uses this to calculate the consistency, thereby stabilizing the consistency value.
[0050] (Step S6)
[0051] Return to Figure 2 , the control unit 104 determines the presence or absence of the target component based on the degree of consistency. While the determination method is not limited, for example, the control unit 104 may determine that the target component is present if the degree of consistency is above a pre-set threshold, and determine that the target component is absent if the degree of consistency is below the threshold. Alternatively, the control unit 104 may pre-set a first threshold and a second threshold greater than the first threshold, and determine that the target component is absent if the degree of consistency is below the first threshold, and determine that the target component is present if the degree of consistency is above the second threshold.
[0052] Summary of Implementation 1
[0053] As described above, in Embodiment 1, the degree of agreement between the measured mass spectrum and the theoretical mass spectrum is calculated only for the masses of peaks in the theoretical mass spectrum containing the target component, and the presence of the target component is determined based on this agreement. Thus, even if the measured mass spectrum contains peaks other than those of the target component, these peaks are not used in the agreement calculation. This effectively avoids the influence of peaks other than those of the target component, thereby preventing misjudgments in qualitative analysis.
[0054] The mass spectrometry method of this embodiment is not limited to the analysis of chlorinated paraffins described above, but can also be applied to the analysis of compounds containing elements with multiple stable isotopes at non-negligible isotope ratios. The mass spectrometry method of this embodiment can be used with organic compounds such as organic halides and organometallic compounds as analytical components. Examples of organic halides include chlorinated paraffins and organic chlorides such as dioxins, and organic bromides such as brominated flame retardants (e.g., tetrabromobisphenol A) and brominated dioxins.
[0055] [Implementation Method 2]
[0056] In embodiment 1, the method for calculating the theoretical mass spectrum of the analysis object component and the mass spectrum of the measurement object is described, and the method for calculating the consistency is described. The mass spectrum of the measurement object includes not only the peak caused by the compound contained in the measurement object, but also the peak caused by the factors other than the measurement object such as the mass spectrometer 100 itself and the container of the measurement object. In the case where the factors other than the measurement object have the same mass as the analysis object component, that is, when the peak of the factors other than the measurement object becomes the peak at the same position as the analysis object component, it will cause an adverse effect on the measurement (misjudgment). Therefore, in embodiment 2, a technology for reducing the influence of factors other than the measurement object is proposed.
[0057] The mass spectrometer of this embodiment can be the same mass spectrometer as the mass spectrometer 100 described in the first embodiment.
[0058] <Quality Analysis Method>
[0059] Figure 5 Flowchart of the mass spectrometry method of embodiment 2. Steps S1 to S6 are the same as those of embodiment 1, and therefore their description is omitted. In this embodiment, step S7 is implemented before step S5. In step S7, the control unit 104 subtracts the mass spectrum (first mass spectrum) obtained in step S3 by operating the mass spectrometer 100 in advance in the absence of the object to be measured (hereinafter sometimes referred to as the "second mass spectrum") . Specifically, the control unit 104 subtracts the ion intensity of the peak of the second mass spectrum from the ion intensity of the peak of the first mass spectrum. Here, as shown in FIG. Figure 3 As explained, the calculation in this step can be performed by taking the average of the ion intensities at the specified width W of each peak as the ion intensity of that peak. The second mass spectrum only includes peaks caused by factors other than the object being measured, such as the mass spectrometer 100 and the container containing the object being measured. Therefore, the processing in step S7 yields a mass spectrum consisting solely of the object being measured. Comparing this mass spectrum with the theoretical mass spectrum can prevent misjudgment.
[0060] Step S7 may be performed between step S3 and step S5, and the order of step S4 and step S7 is not limited. In addition, before measuring the measurement object in step S3, a mass spectrum may be acquired in a state without the measurement object.
[0061] Summary of Implementation 2
[0062] As described above, in the second embodiment, a second mass spectrum obtained without the target object is subtracted from a first mass spectrum obtained by measuring the target object, and the degree of agreement between the resulting mass spectrum and the theoretical mass spectrum of the target component is calculated. This eliminates the influence of peaks caused by factors other than the target object, thereby further improving analytical accuracy compared to the first embodiment.
[0063] [Implementation Method 3]
[0064] In Embodiments 1 and 2, techniques for analyzing components by considering the isotopic abundance ratio of elements within the target component were described. Depending on the target component, the peak positions of homologous compounds may overlap. Failure to separate the peak intensities of the individual homologous compounds can lead to erroneous determinations. Therefore, in Embodiment 3, a technique for separating the overlapping peaks of homologous compounds is proposed.
[0065] The mass spectrometer of this embodiment can be the same mass spectrometer as the mass spectrometer 100 described in the first embodiment.
[0066] <Quality Analysis Method>
[0067] Figure 6 This is a flow chart of the mass analysis method of Embodiment 3. Steps S1 to S6 are the same as those of Embodiment 1, and therefore their description is omitted. In this embodiment, Step S8 is performed before Step S5. In Step S8, when peaks are present at positions of identical mass between components (homologs) with different combinations of carbon numbers x and chlorine numbers y in the theoretical mass spectrum, the control unit 104 separates the ion intensities of the peaks in the mass spectrum obtained in Step S3. An example of a method for separating ion intensities (peak overlap) is described below.
[0068] Figure 7 This is a conceptual diagram of a method for separating ionic strengths. Here, the following description is made using as an example components A and B (chlorinated paraffins) having different combinations of carbon number x and chlorine number y. Figure 7 The mass spectra calculated based on the mass and abundance ratio of component A (component A-1 to A-5) and component B (component B-1 to B-5) are shown in FIG. 5 , each of which has 5 peaks. In addition, the numbers after the letters of each component are the number of peaks contained in each component. 37 The number of Cl. Therefore, if the number increases by 1, the mass will increase by 2. Figure 7In the example, the masses of component A-5 and component B-1 are the same, that is, the peak positions overlap. In this case, the ratio of the existence ratio (vertical axis) of the peaks that do not overlap (for example, component A-2) and the peaks that overlap (component A-5) can be calculated from the theoretical mass spectrum. Therefore, the ion intensity of component A-5 of the mass spectrum obtained in step S3 can be calculated based on the ion intensity of component A-2 and the above ratio. The ion intensity of component B-1 can be obtained from the calculation result of the ion intensity of component A-5. In this way, even if there are peaks of the same mass between component A and component B, the ion intensity can be separated. Here, as shown in reference Figure 3 As described above, the ratio in this step can be calculated by taking the average value of the ion intensities at the predetermined width W of each peak as the ion intensity of the peak.
[0069] In addition, there is no limitation on the peak used in the treatment of this step (peaks that do not overlap between homologues), and the peak with the largest ion intensity can be used, or multiple peaks can be used. Step S8 can be implemented between steps S3 and S5, and the order of steps S4 and S8 is not limited.
[0070] Summary of Implementation 3
[0071] As described above, in Embodiment 3, when components of the same mass exist among homologous series having different combinations of carbon numbers x and chlorine numbers y, the ion intensities of the components of the same mass are separated from the mass spectrum obtained by measuring the object to be measured. Thus, even when homologous series of the same mass (peaks at the same position) exist, they can be compared with the theoretical mass spectrum, thereby preventing misjudgment.
[0072] [Implementation 4]
[0073] In the fourth embodiment, a combination of the second embodiment and the third embodiment will be described.
[0074] Figure 8 4 is a flow chart of the mass analysis method of embodiment 4. The contents of each process of steps S1 to S8 are as described above. Figure 8 As shown, steps S7 and S8 can be performed between steps S4 and S5. Step S7 can be performed between steps S3 and S5, before step S4, or after step S8.
[0075] [Modification]
[0076] The present disclosure is not limited to the above-described embodiments and includes various variations. For example, the above-described embodiments are detailed descriptions for the purpose of explaining the present invention in an understandable manner, and the present invention is not necessarily limited to including all of the structures described. In addition, a portion of a certain embodiment may be replaced with a structure of another embodiment. In addition, a structure of another embodiment may be added to a structure of a certain embodiment. In addition, a portion of the structure of each embodiment may be added, deleted, or replaced with a portion of the structure of another embodiment.
[0077] Label Description
[0078] 100 Mass Analyzer
[0079] 101 Heating Unit
[0080] 102 Ionization Department
[0081] 103 Testing Department
[0082] 104 Control Department.
Claims
1. A mass analysis method using a mass analyzer, characterized in that: include: calculating, by a control unit of the mass spectrometer, the masses of the isotopes of the component to be analyzed and the abundance ratios of the isotopes of the component to be analyzed, based on the molecular formula of the component to be analyzed and the isotope abundance ratios of an element contained in the component to be analyzed and having a plurality of isotopes, thereby calculating a theoretical mass spectrum; ionizing the measurement object by the pre-processing unit of the mass spectrometer; detecting the mass of the ionized ions and the number of ions of each mass by a mass detection unit of the mass analyzer; calculating, by the control unit, a first mass spectrum based on the detection result of the mass detection unit; The control unit compares the theoretical mass spectrum with the first mass spectrum to calculate the degree of consistency only for the masses of peaks present in the theoretical mass spectrum; as well as The control unit determines whether the analyte component is present in the object to be measured based on the degree of coincidence, The quality analysis method further comprises: operating the pre-processing unit and the quality detection unit by the control unit in a state where the measurement object is not present; calculating, by the control unit, a second mass spectrum in the absence of the measurement object based on the detection result of the mass detection unit; and subtracting the second mass spectrum from the first mass spectrum by the control unit before calculating the degree of coincidence, In the judgment, the control unit compares the consistency with a first threshold and a second threshold greater than the first threshold, and judges that the analysis object component does not exist when the consistency is lower than the first threshold, and judges that the analysis object component exists when the consistency is greater than the second threshold.
2. The mass analysis method according to claim 1, wherein The component to be analyzed is an organic halide, When calculating the theoretical mass spectrum, the control unit calculates, for each combination of the carbon number x and the halogen number y of the organic halide, the mass of y+1 isotopes of the organic halide and the abundance ratio of each mass of the organic halide based on the molecular formula of the organic halide and the isotope abundance ratio of the halogen.
3. The mass analysis method according to claim 1, wherein Also includes: Before calculating the degree of coincidence, the control unit separates the ion intensities of the components having the same mass from the first mass spectrum when components having the same mass exist among the homologues of the component to be analyzed.
4. The mass analysis method according to claim 1, wherein The control unit calculates the degree of coincidence based on the ion intensity averaged within a range of a predetermined width of the first mass spectrum.
5. The mass analysis method according to claim 1, wherein The control unit calculates the degree of coincidence using a correlation coefficient of the number of ions of the mass at which the peak exists.
6. The mass analysis method according to claim 1, wherein Also includes: The control unit corrects the mass of the first mass spectrum based on the ionization reaction in the pre-processing unit.
7. The mass analysis method according to claim 1, wherein The analysis target component is an organic chloride.
8. The mass analysis method according to claim 1, wherein The component to be analyzed is an organic bromide.
9. The mass analysis method according to claim 1, wherein The ionization method of the pre-treatment section is atmospheric pressure chemical ionization.
10. A mass analysis device, characterized in that include: a pre-treatment unit for ionizing the object to be measured; a mass detection unit for detecting the mass of the ions ionized by the pretreatment unit and the number of ions of each mass; as well as a control unit that controls the pre-processing unit and the quality detection unit, The control unit performs the following processing: a process of calculating a theoretical mass spectrum by calculating the masses of the isotopes of the analysis target component and the abundance ratios of the isotopes of the analysis target component based on the molecular formula of the analysis target component and the isotope abundance ratios of an element contained in the analysis target component and having a plurality of isotopes; a process of calculating a first mass spectrum based on the detection result of the mass detection unit; a process of calculating the degree of identity by comparing the theoretical mass spectrum with the first mass spectrum only for the masses of peaks having the theoretical mass spectrum; as well as executing a process for determining the presence or absence of the analyte component in the measurement object based on the degree of coincidence, The control unit also performs the following processing: a process of operating the pre-processing unit and the quality detection unit in a state where the object is not being measured; a process of calculating a second mass spectrum in the absence of the measurement object based on the detection result of the mass detection unit; as well as subtracting the second mass spectrum from the first mass spectrum before calculating the degree of identity, In the judgment, the control unit compares the consistency with a first threshold and a second threshold greater than the first threshold, and judges that the analysis object component does not exist when the consistency is lower than the first threshold, and judges that the analysis object component exists when the consistency is greater than the second threshold.
11. The mass spectrometer according to claim 10, wherein The component to be analyzed is an organic halide, In the process of calculating the theoretical mass spectrum, the control unit calculates, for each combination of the carbon number x and the halogen number y of the organic halide, the mass of y+1 isotopes of the organic halide and the abundance ratio of each mass of the organic halide based on the molecular formula of the organic halide and the isotope abundance ratio of the halogen.
12. The mass spectrometer according to claim 10, wherein The control unit also performs the following processing: Before calculating the degree of identity, when components of the same mass exist among homologues of the component to be analyzed, ion intensities of the components of the same mass are separated from the first mass spectrum.
13. The mass spectrometer according to claim 10, wherein The control unit calculates the degree of coincidence based on the ion intensity averaged within a range of a predetermined width of the first mass spectrum.
14. The mass spectrometer according to claim 10, wherein The control unit calculates the degree of coincidence using a correlation coefficient of the number of ions of the mass at which the peak exists.
15. The mass spectrometer according to claim 10, wherein The control unit further performs a process of correcting the mass of the first mass spectrum based on the ionization reaction in the preprocessing unit.
16. The mass spectrometer according to claim 10, wherein The analysis target component is an organic chloride.
17. The mass spectrometer according to claim 10, wherein The component to be analyzed is an organic bromide.