JPS5961773A - Precise measurement of mass - Google Patents

Abstract

PURPOSE:To perform rapid and precise measurement of mass number, by performing operation treatment after the peak profile from a detector and the data signal from a mass marker are stored. CONSTITUTION:The specimen molecule ionized in the mass separation means 2 of a mass analytical apparatus 1 is separaed and detected in a detector 3 by magnetic field scanning and the detected signal is passed through an AD converter to be inputted to a peak discrimination means 6 where the peak profile of a signal equal to or more than a threshold value is stored while a rough mass number from a mass maker 5 is stored. The stored data are subjected to operation treatment by a memory operation means 7 to rapidly calculate a precise mass number. This operation is repeated at every magnetic field scanning.

Description

[Detailed description of the invention] Regarding the method.

In general, accurate mass measurement methods that use a double convergence mass spectrometer to measure the mass number of material ions with high precision are:
By scanning the ionized sample with a magnetic field, the resulting mass spectra are stored in a storage/arithmetic means such as a computer, and after measurement, specific detected peaks are extracted from these mass spectra as shown in Figure 2. In this way, changes in intensity over time are recorded, and the mass number indicated by the detected peak is calculated, and in the end, by the way, in the conventional mass measurement method mentioned above, the mass number obtained with an ion detector is calculated. peak profile data,
All mass number data obtained from mass markers are input into the memory calculation means, regardless of the presence or absence of peaks.
For this reason, unnecessary data is also stored as background data, making it impossible to make effective use of the limited storage capacity, and posing the problem of having to install one with a larger storage capacity than necessary.

The present invention has been made in view of the above problems, and includes:
It is an object of the present invention to provide an accurate mass measurement method that can effectively utilize a memory calculation means and thereby quickly calculate a mass number.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the present invention will be described below with reference to embodiments based on the drawings.

(2) is a mass separation means having an ionization chamber, a magnet, etc., (3) is a detector that detects ions, and (4) is a digital detector that converts analog detection signals detected by detector (3). An analog-to-digital converter that converts into a signal, (5) a mass marker that detects the mass number in the scanning magnetic field from the strength of the scanning magnetic field, and (6) a detection input from the analog-to-digital converter (4). Of the signals, the second
As shown in the figure, it is determined whether the intensity is above the threshold value (a) that determines peak occurrence, and the peak profile (Pi) (P2) (P3)...
. . . and in parallel with the second entry, the mass number input signal from the mass marker (5) is stored. In (7), when the mass separation means (2) completes one magnetic field scan, the peak profile (PI) (P2) (
P3)... and a data signal of a mass number, and is a storage/calculation means for processing a high-resolution mass number.

Next, a method of measuring an accurate mass number using the above-mentioned odd-minute 1,700 mass measuring device (1) will be explained.

The sample molecules ionized by the mass separation means (2) are separated and detected by the detector (3) by magnetic field scanning, and this detection signal is sent to the peak discrimination storage means (6) after passing through the analog-to-digital converter (4). is input. This peak discrimination storage means (6) discriminates whether or not the intensity data of this input signal is equal to or higher than the threshold ha (a), and if it is equal to or greater than the threshold value (a), the peak profile (Pl) (P2) ( P.I.
)... are stored as data, and at the same time, the approximate mass number input from the mass marker (5) is also stored.

At the same time as one magnetic field scan is completed, the peak discrimination storage means (6
) is inputted to the storage calculation means (7),
The storage calculation means (7) performs calculation processing and calculates the exact mass number. Then, the above operation is repeated for each magnetic field scan.

Note that even if the peak discrimination storage means (6) does not store data below the threshold (a), such as background (1)), the timer etc. necessary for data processing are operating and the mass It does not interfere with numerical measurements. Note that the peak discrimination storage means (6) is constituted by a low-level computer, and the storage calculation means (7) is constituted by a ``-''-level computer. The data may be analyzed using a high-level language or the like.

As described above, according to the present invention, the peak profile data signal inputted through the mass separation means and the detector and the mass number data signal inputted from the mass marker are once stored in the peak discrimination storage means, and At that time, instead of storing all the input data as in the past, only the necessary portion of the peak profile is stored, and after one magnetic field scan is completed, the above data stored in the peak discrimination storage means is stored. Since the data signal is output to the storage calculation means, no data signal is input while the storage calculation means is manually inputting the take signal from the peak discrimination storage means, mass separation means, or mass marker, so data analysis is performed during that time. can be performed quickly, and can also perform arithmetic processing on other data. In addition, since only necessary measurement results are input to the storage calculation means, the storage capacity can be reduced compared to the conventional method, which is an excellent advantage.

The drawings show an embodiment of the invention, and FIG. 1 shows a simultaneous curtain.

A flow diagram of the active mass spectrometer, Figure 2 is an explanation of the action (1)
... Partially disassembled mass spectrometer, (2) ... Mass separation means, (3) - Detector, (5) ... Mass marker, (6) ... Peak discrimination storage means, ( 7)...
Arithmetic storage means, (a) --Threshold value, (Pl) (
P2) (P3) - Peak profile.

Patent applicant: Shimadzu Corporation Agent: Patent attorney Kazuhide Okada Figure 1 7 Figure 2 −1←CoυNTER

Claims (1)

[Claims] (1) Ions that have been mass separated by the mass separation means are detected by a detector, the detected data signal and the data signal from the mass marker are input to the peak discrimination storage means, and the data from the mass marker is input to the peak discrimination storage means. A signal and a peak profile of a data signal from the detector that is equal to or higher than a threshold value are stored, and the data signal stored in the peak discrimination storage means is transmitted to the storage calculation means every time one magnetic field scan is completed. An accurate mass measurement method characterized in that the stored data signal is subjected to arithmetic processing by the storage calculation means to calculate an accurate mass number.