JPH04184166A - Component purity measuring device for chromatogram peak - Google Patents

Abstract

PURPOSE:To easily judge if the measured peak of a chromatogram contains the single component or two or more components, or judge the range of the single component, by measuring the component purity at each point of the peak from the degree of accordance of the spectrum at one position, having the spectrum at the apex of the chromatogram peak as standard. CONSTITUTION:Data is taken in from a detector 20, and memorized in a data memory part. The data is the three-dimensional data which represents the spectrum of the component separated by a column 12 at each time. The data having a specific wave length is selected from the memorized data, and a chromatogram is prepared from the variation through the lapse of time of the light absorbance for the wave length, and displayed on a CRT. The peak is detected from the prepared chromatogram, and the starting point, apex, and the end point of the peak for which the component purity is to be obtained are obtained. Then, the component purity at each point is calculated, and the results of the calculation are assorted according to a previously set purity.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an apparatus for measuring the component purity of a measured peak in liquid chromatography or flow injection analysis.

(Prior art) In liquid chromatography and flow injection analysis, chromatograms are obtained over time, but
Even if the obtained peak has a single shape,
The component contained in that peak is not necessarily single, but two
In some cases, the above components may be included without being separated.6 As a method of measuring whether the obtained chromatogram peak is only a single component, the chromatogram is measured at two different wavelengths using an optical detector. However, a ratio chromatogram method is used in which the purity of the peak component is measured by taking the ratio of the two chromatograms. When a peak is detected and the peak consists of a single component, the wavelength characteristics do not change at any location on the peak, so the ratio of the chromatograms of the two wavelengths is a constant value at any location on the peak. become. On the other hand, if the peak contains two or more components, the proportions of the components will differ depending on the location of the peak, so the wavelength characteristics of the spectrum will differ depending on the location of the peak, and the ratio in the chromatogram will change depending on the location of the peak. do.

(Problems to be Solved by the Invention) When component purity is measured using a specific chromatogram method, it is possible to determine whether the peak is a single component or contains two or more components. However, it is difficult to judge how likely a certain range is to be a single component in the range from the start point to the end point of a peak, and therefore, for example, when performing preparative separation, It is difficult to use specific chromatogram methods to determine the

The present invention can display component purity over the range from the start point to the end point of a chromatogram peak. For example, when performing preparative separation, it is possible to easily know the range suitable for the preparative separation. The object of the present invention is to provide a component purity measuring device.

(Means for solving problems) FIG. 1 shows a block diagram of the present invention.

2 is a data storage unit that stores detection signals from a multi-wavelength detector of the chromatograph; 4 is a chromatogram creation unit that creates a chromatogram for a specific wavelength from the data stored in the data storage unit 2; and 6 is a chromatogram creation unit that creates a chromatogram for a specific wavelength. 8 is a peak detection unit that detects the peaks of the chromatogram, and 8 calculates the degree of coincidence between the spectrum at the peak apex and the spectrum at other positions of the peak for the chromatogram peak, and calculates the component purity at each position of the peak. component purity calculation unit, 10
is a display section that displays the calculated component purity.

(Function) When a chromatogram is created for a certain wavelength from the data obtained by measuring spectra at each time using liquid chromatography or flow injection analysis, one peak will appear as shown in Figure 2 (A), for example. can get. The spectrum at the apex T0 of the peak is shown in the same figure (
B) is 80 (λ). On the other hand, let S(λ) be the spectrum at another arbitrary position T of the peak. Based on the spectrum at the peak apex T, the component purity at any position T of that peak is the spectrum S, (λ) and S(λ)
It can be determined by calculating the degree of matching. For example, the formula for the degree of coincidence representing the component purity is expressed as follows.

For example, the degree of matching can be displayed on a display device in color-coded ranges, or as numerical values on a display device or printer.

(Example) FIG. 3 shows an example of a liquid chromatograph to which the present invention is applied.

12 is a column, and an eluent 14 is sent to the column 12 by a liquid sending pump 16. Eluent pump 16 and column 1
A sample injection section 18 is provided between the columns 1 and 2, and the injected sample is sent to the column 12 together with the eluent.
2 and detected by a detector 20. The eluate that has passed through the detector 20 is discharged to the drain.

The detector 2o is an optical detector capable of measuring a chromatogram and a spectrum at each time point, such as an ultraviolet/visible spectrophotometer. The detection signal of the detector 20 is sent to the data processing device 22 and processed.

Each section in FIG. 1 is realized by a data processing device 22.

The operation of one embodiment will be explained with reference to FIGS. 4 and 5.

Data from the detector 20 is captured and stored in the data storage section. This data is three-dimensional data representing the instantaneous spectra of the components separated in column 12. A specific wavelength is selected from the stored data, and a chromatogram is created from changes in absorbance over time for that wavelength. The chromatogram is displayed on a display unit such as a CRT.

A peak is detected from the created chromatogram, and the starting point T□, apex T0, and ending point T2 of the peak whose component purity is to be determined are determined.

Based on the spectrum of To, the component purity at each point in the range of T□ to T2 is calculated based on the calculation formula (1). The calculation results are classified according to preset purity levels, for example, color-coded according to the range. The color classification is 1. For example, depending on the purity of the ingredients, 0-0.5 ... Red 0.5-0.7 ... Orange 0.7-0.8 ... Yellow 0 .8~1.0 ・・・・・・Green, and so on.

This operation is performed for one peak from the starting point T1 to the ending point T2, and the results are displayed on a display unit such as a CRT in different colors as shown in FIG. 5, for example.

The above operation is repeated for all peaks whose component purity is to be determined.

It is easier to see component purity when it is displayed in different colors as shown in Figure 5, but it is not always necessary to do so; other display methods may be used, such as plotting component purity values over time. .

(Effects of the Invention) In the present invention, the component purity at each point of the chromatogram peak is measured based on the degree of coincidence of spectra at other positions using the spectrum at the apex of the chromatogram peak as a reference, so W! 4. It becomes possible to easily determine whether a determined peak is a single component or contains two or more components, and which range is a single component. As a result, for example, when performing fractionation, it becomes possible to set the fractionation range based on the measurement results of the component purity.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the present invention, FIG. 2 (A) is a diagram showing chromatogram peaks, (B) is a diagram showing an example of the spectrum at the apex and other points, and FIG. 3 is a diagram showing the present invention. FIG. 4 is a flowchart showing the operation of the embodiment, and FIG. 5 is a diagram showing an example of displaying measured component purity in different colors. 2...Data storage unit, 4...Chromatogram creation unit, 6...Peak detection unit, 8...
... Purity calculation section, 10 ... Display section, 20 ...
. . . Detector, 22 . . . Data processing device. Patent applicant: Shimadzu Corporation

Claims (1)

[Claims] (1) A data storage unit that stores detection signals from a multi-wavelength detector of a chromatograph, a chromatogram creation unit that creates a chromatogram for a specific wavelength from the data stored in the data storage unit, and a chromatogram creation unit that creates a chromatogram for a specific wavelength from the data stored in the data storage unit; A peak detection unit that detects the peak of the chromatogram, and a component purity unit that calculates the component purity at each position of the peak by calculating the degree of coincidence between the spectrum at the peak apex and the spectrum at other positions of the peak for the chromatogram peak. A component purity measuring device for chromatogram peaks, comprising a calculation section and a display section that displays the calculated component purity.