JPH04282453A - Data processing apparatus for chromatograph - Google Patents

Abstract

PURPOSE:To prevent the generation of a gap in the signal level of a chromatogram at the time of the alteration in the setting of a measuring condition. CONSTITUTION:When the setting of a measuring condition is altered (ST3), the present signal level is stored in a memory and signal output is held to the level (ST4). Then, the measuring condition is altered (ST5) and, thereafter, a signal level is set to the level stored in the memory (ST6) to reopen the renewal of signal output (ST7).

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data processing device for a chromatograph such as a liquid chromatograph.

0002

[Prior Art] A chromatogram output from a liquid chromatograph has many peaks in time series, but the optimal measurement conditions differ depending on the eluted separated components. For example, the wavelength at which each peak is optimally extracted is different. differ. Therefore,
Automatic settings are made in advance to switch measurement conditions such as wavelength and sensitivity at a predetermined timing (point in time), and when a chromatogram is output, the measurement conditions are changed at that timing. Conventionally, when changing the measurement condition settings, an auto-zero function is executed to forcibly set the signal level to zero.

0003

[Problem to be Solved by the Invention] Since the baseline of a chromatogram fluctuates around zero due to drift and noise, the conventional auto-zero function described above, which forcibly sets the signal level to zero, has problems at the point in time when it is executed, that is. When changing the measurement conditions, a gap occurs in the chromatogram, as shown at t in FIG. 4. This gap is
Not only does it make the chromatogram look bad, but the gap can be mistaken for a peak during data processing.

The present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to provide a data processing device for chromatography in which a gap does not occur in the signal level of a chromatogram when changing the settings of measurement conditions. The purpose is

[0005]

[Means and effects for solving the problems] The chromatograph data processing device of the present invention converts a signal from a chromatograph into a digital signal using an A/D converter and captures the digital signal.
and means for changing the settings of the optimal measurement conditions on the detector at a predetermined timing, means for storing the signal value immediately before the setting change when changing the settings of the measurement conditions, and means for changing the signal output to the signal value when changing the measurement conditions. and means for setting the signal level to the stored signal value level and restarting updating of the signal output after changing the setting of the measurement conditions.

In this chromatographic data processing device, when the timing for changing measurement condition settings such as wavelength switching comes while outputting a signal, the signal value immediately before the setting change is stored, and when the measurement condition setting is changed, The signal value is held, and after the setting is changed, the signal level is set to the stored signal value level, and the update of the signal output is restarted. Since the signal value level is the same before and after the measurement condition settings are changed, a gap in the chromatogram does not occur when the settings are changed, as shown at t in FIG. 3.

[0007]

[Examples] The present invention will be explained in more detail with reference to Examples below. FIG. 1 is a block diagram of a chromatographic data processing apparatus in which the present invention is implemented. The data processing device 1 includes an A/D converter 11 that converts a chromatogram applied from the liquid chromatograph 2 into a digital signal;
A floppy disk 12 for storing captured chromatogram data, and a floppy disk 12 for storing captured chromatogram data.
A CPU 13 that executes peak detection, peak area calculation, and other analytical processing operations according to a predetermined program, a ROM 14 that stores the programs of this CPU 13, and a RAM 15 that is used for calculations and temporary storage of data, etc.
Key input section 1 for inputting various parameters and numerical values
6, and a display 1 that displays chromatograms, etc. and analysis results.
7 and a printer 18. However, the configuration of such a data processing device itself is not particularly new.

FIG. 2 is a flow diagram for explaining the operation of an embodiment of the present invention in the data processing apparatus. Every time the operation starts and the data acquisition timing arrives, the determination in step ST1 becomes YES, and data acquisition is performed. The data is memorized and the display 1
7, etc., and returns to step ST1, and thereafter continues to capture data at each data capture timing. on the other hand,
In a state where the data import timing has not arrived, it is determined whether or not it is time to change the conditions during that time (step ST
3). Normally, data is captured by repeating steps ST1 and ST2, but for example, as shown in FIG.
If the wavelength is switched to a predetermined wavelength at time t1 shown in , this determination becomes YES, and then the current signal level is stored in memory and the signal output is held at that value (
Step ST4). In this state, switching conditions such as wavelength and sensitivity are changed (step ST5). In the switched state, that is, after the condition has been changed, the signal level is set to the level previously stored in step ST4 (step ST6). Therefore, the same level is maintained before and after the condition setting is changed. Thereafter, the update of the signal output is restarted (step ST7), and the original step ST1 is resumed.
, and will continue to import data in the same way.

In this example, no gap appears before and after changing the conditions at t, and a good-looking chromatogram can be obtained. In this embodiment, even if the baseline is no longer 0 due to drift, signal acquisition after the change is resumed according to that level, so the continuity of the baseline is maintained and no gaps occur. do not have.

0010

[Effects of the Invention] According to the present invention, the signal level is memorized before setting or changing, and after the setting is changed, the output is adjusted to the signal level value and the signal output is continued thereafter. There will be no gaps and it will look better. Furthermore, there is an effect that the data processing device no longer mistakenly recognizes a gap as a peak.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a data processing device in which the present invention is implemented.

FIG. 2 is a flowchart showing processing performed by the data processing device when data is taken in and measurement conditions are changed.

FIG. 3 is a chromatogram waveform diagram when changing measurement conditions in the data processing apparatus of the embodiment.

FIG. 4 is a diagram showing a chromatogram waveform when changing measurement condition settings of a conventional chromatographic data processing device.

Claims (1)

[Claims] 1. A data processing device for a chromatograph, which converts a signal from a chromatograph into a digital signal using an A/D converter and captures the digital signal, and is capable of changing the settings of a detector to set optimal measurement conditions at a predetermined timing. means for storing the signal value immediately before the setting change when changing the setting of the measurement condition; means for holding the signal output at the signal value when changing the measurement condition; 1. A chromatographic data processing device, comprising means for setting a signal value level and restarting updating of the signal output.