JPS59164954A - Mass analysis device - Google Patents

Abstract

PURPOSE:To enable a quick capture of the appearance of an objective substance by discriminating the display position corresponding to the time at which a selected mass spectrum appears. CONSTITUTION:A mass spectrum signal obtained from GC-MS1 for repeatedly sweeping mass number is inputted into an arithmetic processing section 21 composed of a CPU and once memorized into a memory 22. A processing section 21 memorizes input information from a keyboard 23 into a memory 24 while an arithmetic processing is executed according to a specified program and the results thereof supplied to a display section 25. In this case, as the GC-MS1 sweeps mass number at a repetition cycle of 1sec, the processing section 21 adds up heights of spectral peaks respectively contained in mass spectrum signals and displays RIC.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mass spectrometer that can immediately determine the appearance of a target component, and is particularly suitable for use in a device that combines a gas chromatograph and a mass spectrometer.

Conventionally, GC-MS, which combines a gas chromatograph (GC) and a mass spectrometer (MS), has been widely used as a means for analyzing inorganic substances, organic substances, and the like. This Go-MS
In this method, a mixture sample is separated and developed into each component by GC, and each of the separated components is sequentially introduced into an MS.
A RIC that shows the temporal change in the total amount of ions included in a specific mass range based on the mass spectrum data obtained by performing repeated mass number sweeps at short intervals in S.
(reconstructed ion chromatogram) etc. In FIG. 1, RIC is obtained as a curve plotting the total amount of RIC. and,
The RIC is displayed on the screen of the display device with the horizontal axis as the time axis, and printed out if necessary.

By the way, when identifying a specific component in a multi-component mixture using GC-MS, conventionally it is done by focusing on the retention time (retention time) from when the sample is injected until it appears as a peak in RIC. The usual procedure was to get a rough idea from the retention time, and then refer to the mass spectrum when the peak appeared to determine the specific component. However, with this conventional method, there is a problem that when changing the GC column or measurement conditions, the retention time of each component, which should be the standard, changes itself, and it requires skill to estimate the retention time. ,
Moreover, it took a long time to identify it.

The present invention has been made in view of the above-mentioned points,
The mass number of each peak included in the mass spectrum of a substance and the intensity ratio of each peak are unique depending on the substance. For mass spectra obtained repeatedly during analysis, check whether the spectral intensity ratio at the pre-entered mass number(s) matches the ratio value entered in advance. A marker is displayed at the display screen position corresponding to the point at which a mass spectrum that meets the conditions appears, and the color and brightness of that position are changed to draw the operator's attention to the known substance. Appearance and its location (time)
It is designed to inform you.

Hereinafter, the present invention will be explained in detail based on the drawings.

FIG. 2 is a block diagram showing an embodiment of the present invention, in which a mass spectrum signal obtained from a GC-MSI in which mass number sweeps are repeatedly performed is manually inputted to an arithmetic processing unit 21 constituted by a CPU, and is stored in a memory. 22 is temporarily stored. The arithmetic processing unit 21 stores information entered manually from the input unit 23 configured with a keyboard or the like in the memory 24, and
Predetermined arithmetic processing is performed according to a pre-stored program, and the results are displayed on the display section 25.

In the above-described configuration, if the GC-MSI performs a mass number sweep at a repetition period of, for example, 1 second, the arithmetic processing unit 21 receives the mass spectrum signals So, Sl, and S2 sent from the GC-MSI every second. ．． S3. ...The heights of the spectral peaks included in each spectral signal are summed up and the total amount of ions in each spectral signal T(,,
T1 , T2 , T3 , = are calculated, and the calculated To
.

The values of Ti, T2, Th, . do.

As mentioned above, conventionally, a rough idea was obtained based on this RIC&CO, and the target component was identified by referring to the mass spectrum at that time.

By the way, if a mass spectrum consisting of the main peaks of A-F as shown in Figure 4 is obtained for a known substance X+, then the mass number Ma-Mf of peak A-F and the intensity ratio of peak A-F are is unique to the substance X. Therefore, the mass numbers Ma to Mf of the peaks A to F and the intensity ratios of the peaks A to F are memorized in advance, and the GC-MSI
For the mass spectra sent sequentially from Can be identified instantly.

At this time, it is not necessarily necessary to provide information about all peaks; if a substance can be accurately identified with a small amount of information, it is sufficient to simply specify the mass number and intensity ratio of two peaks. For example, substance X is a chlorine atom cl
In the case where CL is included in the peak A in Figure 4, using the fact that the abundance ratio of C) with an atomic weight of 35 and C1 with an atomic weight of 37 is 3:l, C/' (atomic weight 35)
(for example, mass number Ma-200) and peak A containing C (37), which is larger by mass number 2 than that (for example, mass number Ma-200)
' (quality fl & 202) mass number of two peaks 200.
202 and an intensity ratio of 3:l to specify substance X.

The information on the mass number of 200.202 and the information on the intensity ratio of 3:1 are inputted by the operator from the input section 23 and stored in the memory 24. Then, the arithmetic processing unit 21 executes the GC-M in parallel with the task of obtaining and displaying the RIC described above.
The spectral intensities of mass numbers 200 and 202 in the mass spectrum signals sequentially sent from the SI are sampled, and the intensity ratio is determined. If substance X appears at time tn in FIG.
For example, a marker Z as shown in FIG. 3 is displayed on the screen corresponding to . Therefore, the operator can immediately know that substance X has appeared at time tn.

In addition,. If the spectral intensities of mass numbers 200 and 202 sampled in the arithmetic processing section 2I are displayed as shown by broken lines in FIG.
A mass chromatographic transfer of 0.02 is obtained.

Needless to say, the marker may be displayed on the mass chromatogram, or may be displayed on both the RIC and the RIC.

Note that the present invention is not limited to the embodiments described above, and can be modified in many ways. For example, if we add information on the retention time of a substance to the information on mass number and intensity ratio, we get
Needless to say, the accuracy of identifying substances becomes even higher.

Furthermore, in the above embodiments, a marker is displayed, but it is not limited to the marker, as long as the position where it appears can be displayed distinguishably from other parts. Alternatively, a vertical line may be displayed at the position of time tn so as to cut the RIC and the mass chromatogram.

As described in detail above, according to the present invention, it is determined that the target substance has appeared based on the mass number information stored in advance and the spectral intensity ratio information, and the corresponding position of the RIC and/or mass chromatogram is determined. Since it is displayed separately from others, the appearance of the target substance can be immediately known.

[Brief explanation of drawings]

Figure 1 is a diagram for explaining R and J"C, Figure 2 is a block diagram showing an embodiment of the present invention, Figure 3 is a diagram showing the screen of the display section, and Figure 4 is a diagram for explaining the known substance X. It is a diagram showing a mass spectrum of. ■...G C-MS, 21... Arithmetic processing section 22, 24... Memory 23... Input section 25...
・Display section Patent applicant: JEOL Co., Ltd. Agent Patent attorney: Hiroo Suzuki Figure 2 Figure 3, 6 Figure 4 ′ Liao

Claims (1)

[Claims] While performing repeated mass number sweeps, information on the addition of spectral peak intensities included in mass spectra obtained by mass number sweeps and/or information on spectral peak intensities at specific mass numbers in the mass spectra is sent to a display device. A mass spectrometer configured to display the temporal change includes a means for specifying a plurality of mass numbers, a means for specifying the intensity of a peak having the plurality of mass numbers, and a means for specifying the intensity of a peak having the plurality of mass numbers, and a means for specifying the intensity of a peak having the plurality of mass numbers, and a means for specifying the intensity of a peak having the plurality of mass numbers. discriminating means for discriminating whether the ratio of spectral intensities at each of the specified mass numbers is substantially equal to the specified intensity ratio for each mass spectrum selected by the discriminating means; A mass spectrometer characterized by comprising display control means for displaying a position on the display device that corresponds to a time when a spectrum appears, distinguishing it from others.