Analysis method and program

Abstract

To solve the problem in which: in a conventional analysis method using a chromatograph, a component to be detected may not be determined to be detected and may be overlooked if identification of peaks and waveform processing are inappropriate.SOLUTION: An analysis method includes: analyzing a reference sample containing a predetermined quantity of predetermined component to determine a reference detection value that is a detection value of the predetermined quantity of predetermined component from an analyzer; calculating, based on the reference detection value, a determination reference value that is a standard for determination as to whether the concentration of a component to be detected in a sample to be measured is equal to or more than a reference concentration or equal to or less than the reference concentration; and analyzing the sample to be measured by the analyzer, and when a detection value exceeding the determination reference value is detected in a peak detection time zone corresponding to the component to be detected, determining that the component to be detected is detected.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to an analysis method and a program.

Background Art

[0002] For the analysis of whether a regulated substance or the like is contained in an analysis sample at a reference concentration or higher, so-called GC / MS or LC / MS analyzers, which combine a gas chromatograph, a liquid chromatograph, or those chromatographs with a mass spectrometer, are widely used (see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a chromatograph, even when the same amount of a component to be detected is analyzed, the measured amount of the component to be detected may change depending on the state of the chromatograph (change over time) during measurement. Therefore, depending on the state of the chromatograph, there is a risk of overlooking, for example, the detection that a regulated substance is present in an amount equal to or greater than a reference amount (reference concentration). In addition, in a conventional analysis method using a gas chromatograph, when the identification of a detected peak or the cut waveform processing is inappropriate, even when the component to be detected is contained at a high concentration, it may not be possible to determine this as the component to be detected and it may be overlooked.

Means for Solving the Problems

[0005] The analysis method according to the first aspect analyzes a reference sample containing a predetermined amount of a predetermined component using an analyzer equipped with a chromatograph, and obtains a reference detection value which is the detection value of the predetermined amount of the predetermined component by the analyzer. Based on the reference detection value, a determination reference value which is a criterion for determining whether the concentration of the component to be detected in the sample to be measured is equal to or higher than a reference concentration or equal to or lower than the reference concentration is calculated. When the analyzer analyzes the sample to be measured and a detection value exceeding the determination reference value is detected in the peak detection time zone corresponding to the component to be detected, it is determined that the component to be detected has been detected. The program according to the second aspect controls an analyzer equipped with a chromatograph using a computer to analyze a reference sample containing a predetermined amount of a predetermined component, obtains a reference detection value which is the detection value of the predetermined amount of the predetermined component by the analyzer, calculates a determination reference value which is a criterion for determining whether or not a component to be detected is present in a sample to be measured at a concentration equal to or higher than a reference concentration based on the reference detection value, analyzes the sample to be measured with the analyzer, and when a detection value exceeding the determination reference value is detected in the peak detection time zone corresponding to the component to be detected, causes the process of determining that the component to be detected has been detected to be performed.

Advantages of the Invention

[0006] According to the present invention, it is possible to accurately determine whether or not a component to be detected is present in an amount equal to or more than a reference amount (for example, a reference concentration) by correcting the change over time of the chromatograph.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0008] (First Embodiment of the Analysis Method) FIG. 1 is a diagram showing an example of an analyzer 100 for performing analysis by the analysis method of the first embodiment. The analyzer 100 includes a chromatograph 10, a mass spectrometry section 40, and a control section 20 for controlling these components. The chromatograph 10 is, for example, a gas chromatograph, and includes a separation column 14, a column oven 15 housing the column 14, a sample injection section 11 and a sample vaporization chamber 12 provided at the inlet of the column 14. Further, it includes a switching valve 16 provided at the outlet of the column 14, a detector 17 such as an FID detector, and a GC control section 18 for controlling each of these components.

[0009] The mass spectrometry section 40 is, for example, a quadrupole type mass spectrometer, and includes a quadrupole mass filter 45 for separating ions according to m / z and an ion detector 46. The mass spectrometry section 40 further includes a sample introduction section 41 that receives the supply of sample gas from the switching valve 16 via a transfer pipe 19, an ionization section 42, an ion optical system 44, and an MS control section 49 for controlling each of these components. The ionization section 42, the ion optical system 44, and the quadrupole mass filter 45 are housed in a vacuum vessel 47, and the vacuum vessel 47 is evacuated by a vacuum pump 48. The ionization section 42 is not limited to an electron ionization device that performs ionization by electrons (e-) from the illustrated filament 43, and other types of ionization devices can also be used.

[0010] The control unit 20 controls the chromatograph 10 and the mass spectrometer 40 via the network cable NW, obtains measurement data from the chromatograph 10 and the mass spectrometer 40, and analyzes and processes the acquired data.

[0011] The control unit 20 includes a CPU (Central Processing Unit) 22 which is a central processing unit, a memory 23, a display device (display unit) 24 composed of an LCD (Liquid Crystal Display) etc., an input unit 25 composed of a keyboard, a mouse etc., and a storage unit 30 composed of a large-capacity storage device such as a hard disk and an SSD (Solid State Drive). The storage unit 30 is provided with an OS (Operating System) 35, a control program 31 for controlling the chromatograph 10 and the mass spectrometer 40 and processing the measured data, a compound library 32, a setting storage unit 33, and a measurement data storage unit 34.

[0012] The compound library 32 stores identification information such as the name of the compound, structural formula, retention time for various columns, mass spectrum, etc. as information necessary for the analysis of various compounds. The control unit 20 further includes an interface (I / F) 21 for controlling direct connection with an external device and connection via a network such as a LAN (Local Area Network) with an external device etc. And the control unit 20 is connected to the GC control unit 18 and the MS control unit 49 via the network cable NW by the I / F 21.

[0013] The CPU 22, the memory 23, the storage unit 30, and the interface 21 constitute a computer. The memory 23 stores various information described later through the CPU 22 controlled by the control program 31. The control program 31 can control the control unit 20 including the CPU 22 to transmit and save analysis data to an external server 29 via the network cable NW.

[0014] Figure 2 shows a flowchart when the CPU 22 controls the control unit 20 to execute the analysis method of the first embodiment according to the control program 31. Hereinafter, the analysis method of the first embodiment will be described along the flowchart shown in Figure 2. Note that the CPU 22 included in the control unit 20 controls each unit by the control program 31, but the CPU 22, which is the execution subject, is omitted in the following description of each step.

[0015] (Calibration of the analyzer) In step S101, the control unit 20 causes the display unit 24 to display a message prompting the user to inject a reference sample into the sample injection unit 11 of the chromatograph 10. When the user injects the reference sample into the sample injection unit 11 and inputs information indicating that the reference sample has been injected into the input unit 25, in step S102, the control program 31 determines that the sample has been injected and proceeds to step S103.

[0016] The reference sample is a sample containing one or more known predetermined components in known predetermined amounts. By analyzing the reference sample by the analyzer 100 in step S103, the detection sensitivity of the analyzer 100 for each predetermined amount of the predetermined component can be confirmed (calibrated). A sample containing a known predetermined amount of a predetermined component is, for example, a sample obtained by collecting a sample containing the predetermined component at a known concentration in a known amount. The predetermined amount is obtained by multiplying the amount (mass or volume) by the concentration (mass concentration or volume concentration).

[0017] The reference sample injected into the sample injection unit 11 of the chromatograph 10 in step S103 is vaporized in the sample vaporization chamber 12 and moves through the column 14 together with the carrier gas. Then, the reference sample is separated by the column 14 for each component over time and reaches the branch valve 16 after a predetermined retention time. In the first embodiment, the reference sample reaches the detector 17 from the branch valve 16 and is detected by the detector 17. The detected amount detected by the detector 17 is sent to the GC control unit 18 and further sent to the control unit 20.

[0018] FIG. 3(a) is a graph showing an example of the analysis result of the reference sample in step S103. The horizontal axis of the graph represents the elapsed time (seconds) since the reference sample was injected into the sample injection unit 11 of the chromatograph 10 (or since the heating of the column oven 15 was started), and the vertical axis of the graph represents the detection amount by the detector 17. In the example shown in FIG. 3(a), the reference sample contains two known components (component A and component B), and in the detection result of FIG. 3(a), a detection peak curve Ca corresponding to component A and a detection peak curve Cb corresponding to component B appear.

[0019] In step S104, the control unit 20 causes the peak height values of the detection peak curve Ca and the detection peak curve Cb to be calculated, and stores them as the reference detection value Da for component A and the reference detection value Db for component B, respectively. In other words, the reference detection value Da and the reference detection value Db are the peak height values of the detection amounts detected by the detector 17 when known amounts of component A and component B are injected into the chromatograph 10, respectively. Therefore, in the future, when analyzing a sample containing an unknown amount of component A, the amount of component A in the analyzed sample can be accurately calculated from the ratio of the peak height value of the detection amount detected by the detector 17 to the reference detection value Da, and the amount of component A when the reference detection value Da was determined. The same applies to component B.

[0020] The identification of components A and B and the detection peak curves Ca and Cb is performed based on the elapsed time at which each peak curve appears. The time Ta1 indicated by the dashed line in FIG. 3 represents the predicted start time Ta1 of the detection peak curve Ca of component A, which is the time when the appearance start of the detection peak curve Ca of component A is expected. Also, the time Ta2 indicated by the dashed line represents the predicted end time Ta2 of the detection peak curve Ca of component A, which is the time when the appearance end of the detection peak curve Ca of component A is expected. The predicted start time Ta1 and the predicted end time Ta2 of the peak detection of component A are times that are before and after the retention time of component A (the elapsed time when the peak reaches the maximum value) by a predetermined time difference, respectively, and this time difference is specified by the user, for example. For the predicted start time Tb1 and the predicted end time Tb2 of the peak detection of component B, they may be determined in the same manner as each time of component A. The predicted start time Ta1 and the predicted end time Ta2 of the peak detection of component A, and the predicted start time Tb1 and the predicted end time Tb2 of the peak detection of component B are preferably input in advance by the user to the input unit 25 in step S101, for example. Alternatively, in step S101, the user may input the retention time of each component and the above-mentioned time difference, and the control unit 20 may calculate the predicted start time and the predicted end time of the peak detection from the retention time and the time difference. Alternatively, the user may input identification information such as the names of component A and component B to the input unit 25, and the control unit 20 may read out the predicted start time and the predicted end time of the peak detection for component A and component B from the compound library 32. In this specification, the time zones between the predicted start times Ta1, Tb1 and the predicted end times Ta2, Tb2 of the peak detection are referred to as the peak detection time zones Ta, Tb.

[0021] Note that the reference sample may contain only one of components A or B, and in this case, since there is also only one detection peak curve, the identification of the detection peak curve is not necessary. The reference sample may contain three or more known predetermined components. In the analysis process, in step S104, when the reference detection values Da and Db are calculated and stored, the process proceeds to step S105. At this time, in step S104, the control program 31 causes the control unit 20 to store time information such as the date and time when the reference sample was analyzed in the measurement data storage unit 34 or the memory 23 in the storage unit 30. This time information is not limited to the date and time, and may be, for example, the elapsed time after the operation of the analyzer 100 or the elapsed time since the maintenance of the analyzer 100.

[0022] (Confirmation of the elapsed time since the previous calibration) In step S105, the control program 31 causes the control unit 20 to determine whether or not a predetermined time has elapsed since the analysis of the reference sample in steps S101 to S104 based on the above-mentioned time information stored in the measurement data storage unit 34 or the memory 23 in the storage unit 30 in step S104. If a predetermined time has elapsed, the process returns to step S101, and the control unit 20 causes the reference sample to be analyzed again and the reference detection values Da and Db to be calculated. If a predetermined time has not elapsed, the process proceeds to step S106.

[0023] In step S106, the control unit 20 causes the display unit 24 to display a message prompting the user to input whether to analyze the sample to be measured. When the user inputs to analyze (Yes), the process proceeds to step S107. On the other hand, if the user does not input to analyze (Yes), the process returns to step S105.

[0024] (Calculation of the judgment reference value) In step S107, the control unit 20 calculates a judgment reference value, which is a criterion for determining whether a component assumed to be contained in the sample to be measured is actually contained in the sample to be measured. The judgment reference value is determined based on, for example, environmental standards defined by laws and the like. For example, when the environmental standard for component A is Sa [g / L], the volume of the sample to be measured is V [L], and the mass of component A when the reference detection value Da is calculated in step S104 is Ma [g], the judgment reference value Ja is: Ja = Da×(Sa×V) / Ma ···(1) It is represented by.

[0025] Similarly for component B, when the environmental standard for component B is Sb [g / L], and the mass of component B when the reference detection value Db is calculated in step S104 is Mb [g], the judgment reference value Jb is: Jb = Db×(Sb×V) / Mb ···(2) It is represented by. Note that the volume V [L] of the sample to be measured is common to component A and component B. Note that the calculation of the judgment reference values Ja and Jb does not necessarily have to be performed based on the values of the environmental standards Sa and Sb themselves as described above, and it may be calculated based on values (smaller values) that are more stringent than the environmental standards Sa and Sb.

[0026] When calculating the judgment reference values Ja and Jb, the volume V of the sample to be measured, and the environmental standards Sa and Sb of components A and B may be input by the user to the input unit 25. Note that when the volume of the sample to be measured is always set to a fixed amount, the input of the volume V by the user can be omitted. Also, for the environmental standards Sa and Sb of components A and B, the control program 31 can control the control unit 20 to read them from the compound library 32 based on the identification information of components A and B that has already been input. Note that when the sample to be measured is solid, instead of the above-mentioned volume V, the mass Mv [g] of the sample is used, and for the environmental standard, the content mass per unit mass Sm [g / g] is also used to calculate the above-mentioned judgment reference values Ja and Jb. Specifically, instead of Sa, S, and V in formulas (1) and (2), Mv [g] and Sm [g / g] are used to calculate the judgment reference values Ja and Jb. After calculating the judgment reference value in step S107, proceed to step S108.

[0027] (Analysis of the sample to be measured) In step S108, the control unit 20 causes the display unit 24 to display a message prompting the user to inject the measurement target sample into the sample injection unit 11 of the chromatograph 10. When the user injects the measurement target sample into the sample injection unit 11 and inputs information indicating that the injection of the measurement target sample has been performed to the input unit 25, in step S109, the control program 31 determines that the sample has been injected and proceeds to step S110. The process of analyzing the measurement target sample in step S110 is the same as the process of analyzing the reference sample in step S103 described above, so the description is omitted.

[0028] FIG. 3(b) is a diagram showing a graph of an example of the analysis result of the measurement target sample in step S110. The horizontal axis and the vertical axis of the graph are the same as those in FIG. 3(a) described above. In the example of FIG. 3(b), the measurement target sample also contains component A and component B contained in the above-mentioned reference sample as the target components to be detected (detection target components). In step S111, the control unit 20 calculates the peak height value of the detection peak curve Ga as the reference detection value of component A, which is the detection target component, and the peak height value of the detection peak curve Gb as the reference detection value of component B, which is the detection target component, based on the instruction of the control program 31. Then, in step S112, the control unit 20 determines whether the peak height value of the detection peak curve Ga is greater than the above-mentioned determination reference value Ja based on the instruction of the control program 31.

[0029] When there are a plurality of detection peak curves Ga and Gb, the identification of which peak corresponds to component A or component B is performed based on the above-mentioned peak detection time zone. That is, if the detection peak curve Ga is within the period from the predicted peak detection start time Ta1 of component A to the predicted peak detection end time Ta2 of component A, that is, within or near the peak detection time zone Ta of component A, the detection peak curve Ga is determined to be the peak of component A. The same applies to component B.

[0030] As shown in FIG. 3(b), since the peak height value of the detection peak curve Ga is greater than the determination reference value Ja, the process proceeds to step S113, and it is output that component A has been detected from the sample to be measured. On the other hand, when the peak height value of the detection peak curve Ga is smaller than the determination reference value Ja, the process proceeds to step S114, and it is output that component A has not been detected from the sample to be measured. The output destination in these cases is any one or more of the display unit 24, the memory 23, the measurement data storage unit 34, or the external server 29.

[0031] Note that in this example, since detection is performed on two types of components to be detected (component A and component B), it is preferable that steps S112 to S114 described above are repeatedly performed for component A and component B. As shown in FIG. 3(b), since the peak height value of the detection peak curve Gb is smaller than the determination reference value Jb, for component B, the process proceeds from step S112 to step S114, and it is output that component B has not been detected from the sample to be measured.

[0032] After steps S113 and S114 are completed, the process proceeds to step S115, and the control unit 20 causes the display unit 24 to display a message prompting the user to input whether to continue the analysis. When the user inputs Yes (indicating analysis), the process moves to step S105, and the control unit 20 outputs instructions to each unit to repeat the analysis of the sample to be measured. On the other hand, when the user inputs No (indicating not to analyze), the process ends.

[0033] In the first embodiment described above, the predetermined time in step S105 varies depending on the required accuracy of the analysis (detection). In order to perform more accurate detection, it is necessary to set the predetermined time to about several hours in order to minimize the change over time of the analyzer 100. On the other hand, if a certain degree of change over time is allowed, it may be set to about one month or the cycle of the regular maintenance of the analyzer 100. The change over time refers to changes in the contamination of the device, aging deterioration, changes in the stable state of the device due to differences in the elapsed time since the device was started, differences in the device calibration state, and the like.

[0034] Also, in step S105, not only can it be determined based on the elapsed time after the analysis of the reference sample, but it may also be determined based on the time and day of the week or date at that time, or based on both the time and day of the week or date and the elapsed time. As an example, it can be determined as Yes at a predetermined time every day, or it can be determined as Yes at a predetermined time on a predetermined day or a predetermined day of the week every month. In this case, even if it is the predetermined time, if the reference sample is analyzed within that predetermined time, it can also be determined as No.

[0035] (Modification example of the analysis method) In the above first embodiment, analysis (calibration) is performed using a reference sample containing component A and component B, and analysis of a measurement target sample expected to contain component A and component B is performed. On the other hand, this modification example performs highly accurate analysis for correcting the change over time of the analyzer 100 for the detection target components other than the components used for calibration. Since many parts of the configuration of this modification example are common to the above first embodiment, the description of the parts common to the first embodiment will be omitted as appropriate below.

[0036] FIG. 3(c) is a diagram showing a graph of an example of the analysis result for a measurement target sample containing component C other than component A and component B contained in the reference sample. The horizontal axis and vertical axis of the graph are the same as those in FIG. 3(a) described above. In FIG. 3(c), a detection peak curve Gc of component C is shown at a position corresponding to the peak detection time zone Tc~ (between the predicted peak detection start time Tc1 and the predicted peak detection end time Tc2) of component C on the horizontal axis. Note that the predicted peak detection start time Tc1 and the predicted peak detection end time Tc2 of component C are also determined in the same manner as the predicted peak detection start time Ta1 and the predicted peak detection end time Ta2 of component A described above.

[0037] The broken line Jc in Fig. 3(c) is a judgment reference value Jc that serves as a criterion for determining whether component C is contained in the sample to be measured. In this modified example, the judgment reference value Jc is calculated using the relative response factors Ra, Rb, and Rc of components A, B, and C with respect to the analyzer 100. The relative response factor represents the relative value of the detected amount when a certain amount of each component is analyzed by the analyzer 100. Therefore, for component C, without performing the analysis (calibration) of the reference sample in steps S101 to S104, the change over time of the analyzer 100 can be corrected based on the calibration result of component A or component B.

[0038] As an example, the judgment reference value Jc of component C is determined by Equation (3) or Equation (4) using the volume V [L] of the above-mentioned sample to be measured, the mass Ma [g] of component A during calibration, the mass Mb [g] of component B, the reference detection value Da of component A, the reference detection value Db of component B, and the environmental standard Sc [g / L] of component C. Jc = Da×(Sc×V)×(Rc / Ra) / Ma ···(3) Jc = Db×(Sc×V)×(Rc / Rb) / Mb ···(4) Regarding component C, the calculation of the judgment reference value Jc does not necessarily need to be performed based on the value of the environmental standard Sc itself as described above, and it may be calculated based on a value (a smaller value) that is stricter than the environmental standard Sc. When the sample to be measured is a solid, similar to the cases of Equations (1) and (2) above, instead of V [L] and Sc [g / L] in Equations (3) and (4), the mass Mv [g] of the target sample and the environmental standard Sm [g / g] expressed as the contained mass per unit mass are used to calculate the judgment reference value Jc.

[0039] In this modification example, in step S107 in the flowchart shown in FIG. 2, the control unit causes the display unit 24 to display a prompt for the user to input the identification information of component C, the peak detection time zone Tc, and the value of the environmental standard Sc. In response to this warning display, the user can input these values into the input unit 25. Alternatively, when the user inputs the identification information of component C into the input unit 25, the control program 31 can command the control unit 20 to read out the peak detection time zone Tc of component C and the value of the environmental standard Sc from the compound library 32.

[0040] Also in this modification example, in step S112, it is determined whether the peak height value of the detected peak curve Gc is greater than the reference value Jc. If it is greater, the process proceeds to step S113; if not, the process proceeds to step S114. In the above description, the measurement target sample in this modification example has been described as containing only component C. However, the measurement target sample may contain one or more detection target components in addition to component C. In that case, regarding the peak detection time zone and environmental standard of each detection target component, similar to the values for component C described above, the user can input them into the input unit, or based on the identification information input by the user, the control unit 20 can read out the information stored in the compound library 32.

[0041] Further, the measurement target sample in this modification example may contain component A or component B when calibrated in steps S101 to S104. In that case, the reference values Ja and Jb for component A or component B may be determined by the method described in the above first embodiment.

[0042] In any of the above first embodiment and modification examples, instead of the above peak height value, a so-called area value (integral value) may be used as the reference detection values Da and Db of a predetermined component. The area value is the integral of the detected amount within the range of the peak detection time zone Ta (the range from Ta1 to Ta2) for a detection peak curve such as the detected peak curve Ca in FIG. 3(a). In this case, the judgment reference values Ja, Jb, and Jc are also calculated using the reference detection values Da and Db based on the area values. For the detected amount of the component to be detected in the sample to be measured, instead of the peak height value, the area value is used to compare with the judgment reference values Ja, Jb, and Jc.

[0043] By adopting the area value as the reference detection value of the detection peak curve, it is possible to make a more accurate judgment that is less affected by the noise components contained in the signal of the detected amount. On the other hand, by adopting the peak height value as the reference detection value of the detection peak curve, the reference detection value can be calculated using a simpler processing system. Also, in the above formulas (1) to (4), etc., the judgment reference values Ja, Jb, and Jc are calculated using the masses Ma and Mb of the respective components. However, the calculation can be performed not only using the mass but also using the number of moles.

[0044] Also, when analyzing the reference sample, if the elapsed time when component A or component B in the reference sample is actually detected is different from the peak detection time zone that has been input and stored, it is preferable to re-store the actually measured peak detection time zone from the actually detected peak as the new peak detection time zones Ta and Tb of component A or component B. This is to correct for the possible variation in the retention time due to the aging of the analyzer 100 and the like. However, if the stored peak detection time zone and the detected elapsed time are significantly different (for example, by 10% or more), it is not preferable to re-store them as the peak detection time zones Ta and Tb. The control program 31 preferably displays an error message on the display unit 24 to warn the user of the possibility of an error.

[0045] As shown in FIG. 4, the measured value of the detected amount may have a background BG added. In this case, regardless of whether the peak height value or the area value is adopted as the reference detection value of the detection peak curve Ca2, it is desirable to remove the background BG and calculate the reference detection value.

[0046] As an example, as shown in FIG. 4, when the background BG increases with time, the reference detection value is calculated based on the function BGa obtained by interpolating the background BG at the position (time) of the detection peak curve Ca2. When adopting the peak height value, the peak height value may be the true peak height value Da3 obtained by subtracting the value of the function BGa at that time from the apparent peak height value Da2 of the detection peak curve Ca2. Also, when adopting the area value, the value obtained by subtracting the value of the function BGa from the value of the detection peak curve Ca2 may be integrated between the peak detection time zones Ta (from Ta1 to Ta2), and this integrated value may be used as the area value of the detection peak curve Ca2. In any of the above-described first embodiment and the modification, the chromatograph 10 is not limited to the above-described gas chromatograph, and may be a liquid chromatograph.

[0047] (Effects of the First Embodiment and the Modification) (1) The analysis methods of the above-described first embodiment and the modification analyze a reference sample containing predetermined components A and B in predetermined amounts Ma and Mb using an analyzer 100 using a chromatograph, and obtain reference detection values Da and Db which are the detection values of the predetermined components A and B in the predetermined amounts Ma and Mb by the analyzer 100. Based on the reference detection values Da and Db, determination reference values Ja, Jb, and Jc are calculated as the criteria for determining whether the concentrations of the detection target components A, B, and C in the sample to be measured are equal to or higher than the reference concentration or equal to or lower than the reference concentration. The analyzer 100 analyzes the sample to be measured, and when detection values exceeding the determination reference values Ja, Jb, and Jc are detected in the peak detection time zones Ta, Tb, and Tc corresponding to the detection target components A, B, and C, it is determined that the detection target components A, B, and C are detected. With this configuration, the analyzer 100 can be calibrated by analyzing the reference sample, and the change over time of the analyzer 100 can be corrected. Therefore, it is possible to accurately determine whether or not the detection target components A, B, and C are present in an amount (reference concentration) equal to or higher than the reference amount.

[0048] In a conventional analysis method using a gas chromatograph, even when the detected peak is highly concentrated with the component to be detected, if the identification of the detected peak and the waveform processing are inappropriate, it may not be possible to determine that this is the component to be detected, and it may be overlooked. On the other hand, in the analysis methods of the first embodiment and the modified example, it is determined whether the component to be detected is detected or not based on whether the component to be detected is equal to or higher than the reference concentration, or equal to or lower than the reference concentration, in the peak detection time zone. Therefore, in the analysis methods of the first embodiment and the modified example, it is possible to determine whether the component to be detected is detected or not regardless of the peak identification process and the waveform processing.

[0049] (2) By outputting that the component to be detected is detected or not detected in the peak detection time zone corresponding to the component to be detected, not only the fact that the component to be detected is detected but also the fact that the component to be detected is not detected can be made clear. (3) The reference sample contains a plurality of predetermined components A and B, and by setting the components to be detected A and B to be the same substance as one of the plurality of predetermined components, calibration can be performed using the same components as the components to be detected A and B in the sample to be measured, and a more accurate judgment can be made.

[0050] (4) Assuming that the component to be detected C is a substance different from the predetermined components A and B contained in the reference sample, and the judgment reference value Jc is calculated based on the reference detection values Da and Db of the predetermined components A and B, the reference concentration of the component to be detected C, and the relative response factors Ra, Rb, and Rc between the predetermined components A and B and the component to be detected C, it is possible to make an accurate judgment in which the change over time of the analyzer 100 is corrected even for a component C different from the predetermined components A and B contained in the reference sample used during calibration. (5) By storing time information regarding the time when the reference sample is analyzed in the storage device, information regarding the time when the reference sample is analyzed, that is, calibrated, can be used in subsequent analyses. Based on the time information stored in the memory device, it is determined whether or not a predetermined time has elapsed since the analysis of the reference sample. If a predetermined time has elapsed, the analysis of the reference sample is performed again, thereby further improving the accuracy of the analysis of the sample to be measured.

[0051] (Second Embodiment of the Analysis Method) In the analysis methods of the above-described first embodiment and the modification, the analysis of the reference sample and the analysis of the sample to be measured are performed based on the detection amount obtained by the detector 17 of the chromatograph 10. On the other hand, in the analysis method of the second embodiment described below, the analysis of the reference sample and the analysis of the sample to be measured are performed based on the detection amount obtained by the ion detector 46 of the mass spectrometry unit 40. That is, the detection amount detected by the ion detector 46 is sent to the MS control unit 49 and further sent to the control unit 20. For other configurations of the second embodiment, since they are the same as the analysis methods of the above-described first embodiment and the modification, detailed description thereof is omitted.

[0052] In the analysis method of the second embodiment, the switching valve 16 is set so that the sample output from the column 14 is supplied to the sample introduction unit 41 of the mass spectrometry unit 40. The sample supplied to the sample introduction unit 41 is ionized by the ionization unit 42 as described above, and reaches the quadrupole mass filter 45 that separates ions according to m / z through the ion optical system 44. Then, only ions having a predetermined m / z are selectively transmitted by the quadrupole mass filter 45 and detected by the ion detector 46.

[0053] In accordance with the control program 31, the CPU 22 controls the mass spectrometry unit 40 via the MS control unit 49 so that ions having m / z corresponding to the detection target components A, B, and C are selectively detected during the analysis of the reference sample in step S103 and the analysis of the sample to be measured in step S103. Specifically, in each peak detection time zone Ta, Tb, and Tc of each detection target component A, B, and C, the conditions of the RF voltage applied to the quadrupole mass filter 45 are set so that the quadrupole mass filter 45 selectively transmits ions having m / z corresponding to the detection target components A, B, and C. The ions corresponding to the components A, B, and C to be detected may be so-called quantification ions or confirmation ions for each component.

[0054] (Effect of the analysis method of the second embodiment) (7) In addition to the analysis method of the first embodiment and the analysis methods of the modified examples, the analysis method of the second embodiment uses an analyzer 100 including a mass spectrometry unit 40 at the subsequent stage of the chromatograph 10, and performs analysis of a reference sample and analysis of a sample to be measured based on a detection signal detected by the mass spectrometry unit 40. With this configuration, since the detected amount in which only ions having a predetermined m / z (mass-to-charge ratio) are selected and detected is used, even when the sample to be measured contains components other than the components A, B, and C to be detected, the detected amounts of the components A, B, and C to be detected can be measured with higher accuracy. Thereby, it is possible to more accurately determine whether or not the components A, B, and C to be detected are present in an amount equal to or greater than a reference amount (reference concentration).

[0055] (Embodiment of the program) As described above, in each of the above embodiments and each modification, the above analysis using the analyzer 100 may be performed by recording a program (control program 31) for realizing the above functions on a computer-readable recording medium, reading the program recorded on this recording medium into a computer system, and executing it. Here, the "computer system" is assumed to include an OS (Operating System) and the hardware of peripheral devices. Further, the "computer-readable recording medium" refers to a portable recording medium such as a flexible disk, a magneto-optical disk, an optical disk, a memory card, etc., and a storage device such as a hard disk built in a computer system. Furthermore, the "computer-readable recording medium" refers to something that dynamically holds a program for a short time, like a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line, and may include something that holds a program for a certain time, like a volatile memory inside a computer system that serves as a server or a client in that case. Also, the above program may be for realizing a part of the functions of the control program 31 described above, and may further be realized by a combination with a program already recorded in the computer system for the functions described above.

[0056] Also, the above program can be provided through a recording medium such as a CD-ROM or a data signal such as the Internet. For example, the control unit 20 including the CPU 22, the memory 23, and the storage unit 30 in FIG. 1 receives program provision via a CD-ROM inserted into the disk drive 26. Also, the control unit 20 has a connection function with the network cable NW. The server 29 connected to the network also functions as a server computer that provides the above program and transfers the program to a recording medium such as the storage unit 30. That is, the program is carried by a carrier wave as a data signal and transmitted via the network cable NW. Thus, the program can be supplied as various forms of computer-readable computer program products such as a recording medium and a carrier wave. Note that not all steps of the flowchart shown in FIG. 2 are necessarily required to be executed.

[0057] (Effects of Program Embodiments) (8) The program 31 of the embodiment controls the analyzer 100 using the chromatograph 10 with the control unit (computer) 20 to analyze a reference sample containing a predetermined component in a predetermined amount, obtains a reference detection value which is a detection value of the predetermined amount of the predetermined component by the analyzer, calculates a determination reference value which is a determination reference for whether or not a detection target component exists in a measurement target sample at a reference concentration or higher based on the reference detection value, analyzes the measurement target sample with the analyzer 100, and when a detection value exceeding the determination reference value is detected in the peak detection time zone corresponding to the detection target component, determines that the detection target component has been detected, and causes the processing to be performed. With this configuration, the analyzer 100 can be calibrated by analyzing the reference sample, and the change over time of the analyzer 100 can be corrected. Therefore, it is possible to accurately determine whether or not detection target components A, B, and C exist in the analyzer 100 in an amount (reference concentration) equal to or higher than the reference amount. (9) By adopting a configuration in which the determination reference value is calculated based on the reference detection value of the predetermined component, the reference concentration of the detection target component, and the relative response factor between the predetermined component and the detection target component, it is possible to make an accurate determination in which the change over time of the analyzer 100 is corrected even for a component C different from the predetermined components A and B contained in the reference sample used at the time of calibration.

[0058] In the above, various embodiments and modifications have been described, but the present invention is not limited to these contents. Also, each embodiment may be applied alone or in combination. Other aspects conceivable within the scope of the technical idea of the present invention are also included in the scope of the present invention.

[0059] The disclosure content of the following priority basis application is incorporated herein by reference. Japanese Patent Application No. 2018-220328 (filed on November 26, 2018)

Description of Reference Numerals

[0060] 100… Analyzer, 10… Chromatograph, 11… Sample injection unit, 14… Column, 16… Branch valve, 17… Detector, 18… GC control unit, 20… Control unit, 30… Memory unit, 31… Control program, 40… Mass spectrometry unit, 45… Quadrupole mass filter, 46… Ion detector, 49… MS control unit, Da, Db… Reference detection values, Ja, Jb, Jc… Judgment reference values

Claims

1. An analytical method for determining whether a component to be detected is detected in a sample to be measured, comprising: analyzing a reference sample containing a predetermined amount of a predetermined component, which is a substance different from the component to be detected, using an analytical apparatus equipped with a chromatograph, and obtaining a reference detection value which is the detection value of the predetermined amount of the predetermined component by the analytical apparatus; calculating a determination reference value, which is a determination reference for whether the concentration of the component to be detected in the sample to be measured is equal to or higher than a reference concentration or equal to or lower than the reference concentration, based on the ratio of the reference concentration of the component to be detected to the predetermined amount of the predetermined component in the reference sample, the reference detection value of the predetermined component, the volume or mass of the sample to be measured, and the relative response factor between the predetermined component and the component to be detected; analyzing the sample to be measured using the analytical apparatus, and when a detection value exceeding the determination reference value is detected in the peak detection time zone corresponding to the component to be detected, determining that the component to be detected having a concentration equal to or higher than the reference concentration is detected, and when a detection value exceeding the determination reference value is not detected in the peak detection time zone corresponding to the component to be detected, determining that the component to be detected having a concentration equal to or higher than the reference concentration is not detected.

2. The analytical method according to claim 1, wherein: an output is provided indicating that the component to be detected is detected or not detected in the peak detection time zone corresponding to the component to be detected.

3. The analytical method according to claim 1 or claim 2, wherein: the detection value is the peak height value of the detection signal detected by the analytical apparatus.

4. Analyzing a reference sample containing a predetermined amount of a predetermined component using an analytical apparatus equipped with a chromatograph, and obtaining a reference detection value which is the detection value of the predetermined amount of the predetermined component by the analytical apparatus; Calculating a determination reference value, which is a determination reference for whether the concentration of the component to be detected in the sample to be measured is equal to or higher than a reference concentration or equal to or lower than the reference concentration, based on the ratio of the reference concentration of the component to be detected to the predetermined amount of the predetermined component in the reference sample, the reference detection value of the predetermined component, and the volume or mass of the sample to be measured. When the analysis device analyzes the measurement target sample and a detection value exceeding the determination reference value is detected in the peak detection time zone corresponding to the detection target component, it is determined that the detection target component having a concentration equal to or higher than the reference concentration is detected. When a detection value exceeding the determination reference value is not detected in the peak detection time zone corresponding to the detection target component, it is determined that the detection target component having a concentration equal to or higher than the reference concentration is not detected, and The detection value is an integrated value obtained by integrating a detection signal detected by the analysis device over the peak detection time zone of the predetermined component or the detection target component. The analysis method.

5. In the analysis method according to any one of Claims 1 to 4, The analysis device includes a mass spectrometer downstream of the chromatograph, Based on a detection signal detected by the mass spectrometer, the reference sample is analyzed and the measurement target sample is analyzed. The analysis method.

6. Analyze a reference sample containing a predetermined amount of a predetermined component with an analysis device using a chromatograph, and obtain a reference detection value that is a detection value of the predetermined amount of the predetermined component by the analysis device. Calculate a determination reference value, which is a criterion for determining whether the concentration of the detection target component in the measurement target sample is equal to or higher than the reference concentration or equal to or lower than the reference concentration, based on the ratio of the reference concentration to the predetermined amount of the predetermined component of the reference sample, the reference detection value, and the volume or mass of the measurement target sample. When the analysis device analyzes the measurement target sample and a detection value exceeding the determination reference value is detected in the peak detection time zone corresponding to the detection target component, it is determined that the detection target component having a concentration equal to or higher than the reference concentration is detected. When a detection value exceeding the determination reference value is not detected in the peak detection time zone corresponding to the detection target component, it is determined that the detection target component having a concentration equal to or higher than the reference concentration is not detected, and Store time information regarding the time when the reference sample is analyzed in a storage device. The analysis method.

7. In the analysis method according to Claim 6, Based on the time information stored in the storage device, determine whether a predetermined time or more has elapsed since the analysis of the reference sample. The analysis method.

8. In the analysis method according to any one of Claims 4, 6, and 7, The reference sample contains a plurality of the predetermined components, and An analysis method in which the component to be detected is the same substance as one of the plurality of predetermined components.

9. A program used to determine whether a component to be detected has been detected from a sample to be measured, Controlling an analyzer using a chromatograph with a computer to Analyze a reference sample containing a predetermined amount of a substance different from the component to be detected, Obtain a reference detection value, which is the detection value of the predetermined amount of the predetermined component by the analyzer, Calculating a criterion value, which is a criterion for determining whether the component to be detected is present in the sample to be measured at a concentration equal to or higher than the reference concentration, based on the ratio of the reference concentration of the component to be detected to the predetermined amount of the predetermined component in the reference sample, the reference detection value of the predetermined component, the volume or mass of the sample to be measured, and the relative response factor between the predetermined component and the component to be detected, Analyzing the sample to be measured with the analyzer, and when a detection value exceeding the criterion value is detected in the peak detection time zone corresponding to the component to be detected, determining that the component to be detected at a concentration equal to or higher than the reference concentration has been detected; when a detection value exceeding the criterion value is not detected in the peak detection time zone corresponding to the component to be detected, determining that the component to be detected at a concentration equal to or higher than the reference concentration has not been detected. A program for causing the above processing to be performed.

10. Controlling an analyzer using a chromatograph with a computer to Analyze a reference sample containing a predetermined amount of a predetermined component, Obtain a reference detection value, which is the detection value of the predetermined amount of the predetermined component by the analyzer, Calculating a criterion value, which is a criterion for determining whether a component to be detected is present in a sample to be measured at a concentration equal to or higher than a reference concentration, based on the ratio of the reference concentration to the predetermined amount of the predetermined component in the reference sample, the reference detection value, and the volume or mass of the sample to be measured, Analyzing the sample to be measured with the analyzer, and when a detection value exceeding the criterion value is detected in the peak detection time zone corresponding to the component to be detected, determining that the component to be detected at a concentration equal to or higher than the reference concentration has been detected; when a detection value exceeding the criterion value is not detected in the peak detection time zone corresponding to the component to be detected, determining that the component to be detected at a concentration equal to or higher than the reference concentration has not been detected. A program for causing the above processing to be performed, and In the program, A program in which the detected value is an integrated value obtained by integrating a detection signal detected by the analyzer over the peak detection time zone of the predetermined component or the component to be detected.

11. Controlling an analyzer using a chromatograph with a computer to analyze a reference sample containing a predetermined amount of a predetermined component, obtain a reference detection value which is a detection value of the predetermined amount of the predetermined component by the analyzer, calculate a criterion value which is a criterion for determining whether or not a component to be detected is present in a sample to be measured at a concentration equal to or higher than a reference concentration, based on the ratio of the reference concentration to the predetermined amount of the predetermined component of the reference sample, the reference detection value, and the volume or mass of the sample to be measured, analyze the sample to be measured with the analyzer, and when a detection value exceeding the criterion value is detected in the peak detection time zone corresponding to the component to be detected, determine that the component to be detected at a concentration equal to or higher than the reference concentration has been detected, and when a detection value exceeding the criterion value is not detected in the peak detection time zone corresponding to the component to be detected, determine that the component to be detected at a concentration equal to or higher than the reference concentration has not been detected, which is a program for causing such processing to be performed, In the program, A program for further causing a storage device to store time information regarding the time when the reference sample was analyzed.

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