Multiple sample analysis method

Abstract

To provide a multiple sample analysis method which enables efficient analysis of multiple samples having a main constituent in common.SOLUTION: A multiple sample analysis method includes: a first analysis step in which first chromatography analysis is conducted under a condition allowing mutual separation of multiple components, a three-dimensional chromatogram of a sample is acquired, and spectral data of the multiple components respectively is extracted from the three-dimensional chromatogram; a second analysis step in which second chromatography analysis is conducted under a condition that a chromatogram can be obtained in shorter time than in the first chromatography analysis, for other samples with the same main constituent as the sample mentioned above, in order to acquire three-dimensional chromatograms of the other samples; and a peak separation step for applying peak separation processing based on the spectral data extracted in the first analysis step, to the three-dimensional chromatograms of the other samples that were acquired in the second analysis step, in order to acquire peak separation data for the other samples in which peaks of the multiple components contained in the other samples are mutually separated.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a multiple sample analysis method for obtaining chromatogram data for multiple samples having a common main component, in which the peaks of the components are separated from each other. [Background technology]

[0002] In the pharmaceutical industry and the like, it is sometimes necessary to quantify the concentrations of impurities contained in multiple samples that share a common main component. Liquid chromatography analysis is a common method for quantifying multiple components contained in a sample (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6260709 Summary of the Invention [Problem to be solved by the invention]

[0004] In order to quantify each of a plurality of components contained in a sample using liquid chromatography analysis, it is necessary to separate the peaks of the plurality of components from each other. When a sample contains a mixture of a plurality of components with similar properties, in order to completely separate the peaks of those components, it is necessary to adjust the analytical conditions, such as adjusting the packing material packed in the analytical column, lengthening the overall length of the analytical column, or narrowing the inner diameter of the analytical column to extremely reduce the flow rate of the mobile phase. As a result of performing the analysis under such analytical conditions, it takes a long time for all the components in the sample to elute from the analytical column, and it takes a long time to complete the analysis of one sample. However, when the number of samples to be analyzed is huge, it is not realistic to perform such a long analysis of all of those samples because of the huge financial, time, and human costs.

[0005] The present invention has been made in consideration of the above problems, and has an object to provide a multiple sample analysis method that can efficiently analyze multiple samples that have a common main component. [Means for solving the problem]

[0006] The multiple sample analysis method of the present invention includes a first analysis step of performing a first chromatography analysis using a photodiode array for at least one sample under conditions capable of separating a plurality of components contained in the at least one sample from one another to obtain a three-dimensional chromatogram of the at least one sample, and extracting spectral data of each of the plurality of components contained in the at least one sample from the three-dimensional chromatogram of the at least one sample; a second analysis step of performing a second chromatography analysis using a photodiode array for another sample having the same main component as the at least one sample under conditions that allow a three-dimensional chromatogram to be obtained in a shorter time than the first chromatography analysis to obtain a three-dimensional chromatogram of the other sample; and a peak separation step of applying a peak separation process based on the spectral data extracted in the first analysis step to the three-dimensional chromatogram of the other sample obtained in the second analysis step to obtain peak separation data for the other sample in which peaks of a plurality of components contained in the other sample are separated from one another.

[0007] That is, in the present invention, for some of a plurality of samples that share a common main component, a long-term first chromatographic analysis that provides a high degree of separation is performed to obtain spectral data for the plurality of components, and for the remaining samples, a second chromatographic analysis is performed that provides a three-dimensional chromatogram at high speed but with a lower degree of separation than the first chromatographic analysis, and peak separation data for the remaining samples is obtained by applying a peak separation process based on the spectral data obtained by performing the first chromatographic analysis to the three-dimensional chromatogram with a relatively low degree of separation obtained by the second chromatographic analysis. Effect of the Invention

[0008] As described above, according to the multiple sample analysis method of the present invention, among multiple samples having a common main component, a first chromatographic analysis that takes a long time to obtain a high degree of separation is performed only on some of the samples, and a second chromatographic analysis that obtains a three-dimensional chromatogram at high speed is performed on the remaining samples, although the degree of separation is lower than that of the first chromatographic analysis. This makes it possible to obtain high-precision peak separation data for all samples without having to perform the first chromatographic analysis that takes a long time for all of the multiple samples having a common main component. Therefore, it is possible to efficiently analyze multiple samples having a common main component. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram showing a configuration example of a liquid chromatography analysis device. [Diagram 2] FIG. 1 is a conceptual diagram illustrating an example of a multiple sample analysis method. [Diagram 3] 4 is a flowchart showing an example of a procedure according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] An embodiment of the multiple sample analysis method according to the present invention will now be described with reference to the drawings.

[0011] First, a configuration example of a liquid chromatography analyzer used to carry out a multiple sample analysis method will be described with reference to FIG.

[0012] The liquid chromatography analyzer includes a liquid delivery pump 2, an injector 4, an analytical column 6, a PDA detector 8, an oven 10, and a processor 12. The liquid delivery pump 2 delivers a mobile phase. The injector 4, the analytical column 6, and the PDA detector 8 are connected downstream of the liquid delivery pump 2, in this order from the upstream. The injector 4 is for injecting a sample into the mobile phase delivered by the liquid delivery pump 2. The analytical column 6 is for separating components in the sample injected into the mobile phase by the injector 4. The analytical column 6 is housed inside the oven 10, and is controlled to a temperature according to the analysis conditions. The PDA detector 8 measures the time change in absorbance of the eluate from the analytical column 6 for each wavelength band. That is, the PDA detector 8 acquires analysis data including chromatogram information representing the time change in absorbance in each measurement wavelength band, and spectrum information representing the spectrum at each time during the analysis.

[0013] The arithmetic processing device 12 is realized by a computer device equipped with a CPU (Central Processing Unit), a data storage device, and the like. The arithmetic processing device 12 receives the analysis data output from the PDA detector 8. The arithmetic processing device 12 has a function of performing various analysis processes using the analysis data output from the PDA detector 8. The analysis process functions of the arithmetic processing device 12 include a function of creating a three-dimensional chromatogram having both chromatographic information and spectral information about the sample, a function of extracting spectral data of each of the components separated from each other in the analytical column 6 based on the created three-dimensional chromatogram, and a function of performing peak separation process on the three-dimensional chromatogram using the extracted spectral data. That is, the arithmetic processing device 12 has a function of performing an analysis process once, storing the spectral data extracted from the three-dimensional chromatogram in a database, and using the spectral data stored in the database for peak separation process on another three-dimensional chromatogram.

[0014] Next, the concept of the multiple sample analysis method will be explained with reference to FIG.

[0015] Assume that there are multiple samples 1 to n to be analyzed. These samples 1 to n have a common main component. The purpose of the analysis is to quantify the concentration of each of the multiple components contained in the samples 1 to n, and the analysis is performed using a liquid chromatography apparatus having the configuration shown in Figure 1.

[0016] For sample 1, high-resolution conditions that can obtain high peak resolution between the main component peak and the peaks of nearby components are searched for, and analysis is performed under those high-resolution conditions (first chromatographic analysis). The analysis conditions include elements such as the inner diameter and length of analytical column 6, the type of packing material of analytical column 6, the set temperature of oven 10, the composition of the mobile phase delivered by delivery pump 2, the delivery flow rate of delivery pump 2, and the injection conditions of injector 4. These elements are determined so that at least the peak of the main component of sample 1 and the peaks of other components appearing near the main component are each isolated, and preferably so that all components contained in sample 1 are isolated.

[0017] The first chromatographic analysis produces a three-dimensional chromatogram in which the peaks of multiple components contained in sample 1 are separated from one another, and also produces spectral data for each of the components isolated in the first chromatographic analysis from the three-dimensional chromatogram.

[0018] Generally speaking, an analysis under conditions optimized to completely separate the peaks of multiple components in a sample, such as the first chromatographic analysis, takes a relatively long time to elute all the components from the analytical column 6. Therefore, if such a high-resolution analysis is performed on all of the multiple samples 1 to n, it will take an enormous amount of time to obtain the analysis results for all of the samples 1 to n.

[0019] Therefore, each of samples 2 to n other than sample 1 is analyzed under conditions such that all components are eluted from analytical column 6 in a shorter time than in the first chromatographic analysis (second chromatographic analysis). In the second chromatographic analysis, an analytical column different from that used in the first chromatographic analysis can be used. That is, the first analytical column used in the first chromatographic analysis and the second analytical column used in the second chromatographic analysis may differ from each other in inner diameter, length and / or type of packing material.

[0020] In the three-dimensional chromatogram obtained by the second chromatographic analysis, the intervals between the peaks are shorter and the degree of resolution is lower than that in the first chromatographic analysis, and the peaks of multiple components may overlap. In this case, each analytical data obtained by the second chromatographic analysis is incomplete and cannot be used as it is to quantify the components contained in samples 2 to n.

[0021] In order to eliminate the incompleteness of the analysis data obtained by the second chromatographic analysis, a peak separation process is applied to each analysis data. The peak separation process is a process for estimating the shape and size of each of the peaks of multiple components that overlap each other on a chromatogram. In the peak separation process, in addition to an algorithm that estimates each chromatogram of each component by applying a model function (peak model) such as an EMG (Exponential Modified Gaussian) function to the actual chromatogram waveform (see, for example, International Publication No. 2016 / 035167), an algorithm that mathematically estimates the chromatogram of each component by applying matrix decomposition such as NMF (Non-negative Matrix factorization) to the original three-dimensional chromatogram data without using a model function, and a principal component analysis algorithm such as PCA (principal component analysis) can be used.

[0022] In the above-mentioned peak separation process, it is possible to estimate the number, shape, and size of overlapping peaks on the three-dimensional chromatogram data even when there is no information on the components contained in the sample. However, if there is spectrum data for at least one of the components whose peaks overlap, the accuracy of estimating the number, shape, and size of the overlapping peaks can be improved by using the spectrum data as basic information for the peak separation process.

[0023] In this embodiment, in the peak separation process applied to each analysis data obtained in the second chromatography analysis, at least a part of the spectrum data extracted from the analysis data of the first chromatography analysis is used. Since the samples 1 to n have a common main component, the spectrum data of the main component extracted from the analysis data of the first chromatography analysis can be used in the peak separation process, thereby improving the accuracy of the estimation result obtained by the peak separation process for the analysis data of the samples 2 to n. Note that, when the components contained in the samples 1 to n are all the same, the spectrum data of all the components isolated in the first chromatography analysis can be used in the peak separation process to obtain highly accurate peak separation data for the samples 2 to n.

[0024] An example of the procedure of the multiple sample analysis method of this embodiment will be described with reference to the flow chart of FIG.

[0025] Of the many samples to be analyzed, a high-resolution analysis (first chromatographic analysis) is carried out on some of the samples (which may be one or more samples) such that at least the main component peak is completely separated from the peaks of other components (step 101). The analysis data obtained in the first chromatographic analysis is analyzed using the processor 12 to extract spectral data for each component isolated in the high-resolution analysis (step 102). For some of the samples, peak separation data required for quantifying each component is obtained by the first chromatographic analysis.

[0026] Next, for the remaining samples excluding the part of the samples that have been subjected to the first chromatographic analysis, a low-resolution analysis (second chromatographic analysis) is performed (step 103) in which the resolution between peaks is lower than that of the first chromatographic analysis, but analytical data can be obtained in a shorter time than that of the first chromatographic analysis. As a result, a three-dimensional chromatogram for the remaining samples is obtained (step 104).

[0027] A peak separation process based on the spectral data extracted in step 102 is applied to the three-dimensional chromatogram obtained by the second chromatography analysis (step 105). This peak separation process separates multiple peaks that overlap with each other in the initially incomplete analysis data with high estimation accuracy, resulting in peak separation data that can be used to quantify each component contained in the sample. In other words, by performing the peak separation process in step 105, it is possible to obtain analysis results equivalent to those obtained by performing a long-term high-resolution analysis on all samples.

[0028] As described above, in this embodiment, even if there are a huge number of samples to be analyzed, a first chromatographic analysis is performed for at least one of the samples over a long period of time (and in some cases at high cost) under analytical conditions set to isolate the main component from other components, but the remaining samples are simply subjected to a second chromatographic analysis in a short period of time (and in some cases at low cost), thereby obtaining analytical results equivalent to those obtained by performing a long, high-resolution analysis on all of the samples, thereby significantly reducing the time required to obtain peak separation data for all of the samples.

[0029] The above-described examples merely exemplify the embodiments of the multiple sample analysis method according to the present invention. The embodiments of the multiple sample analysis method according to the present invention are as follows.

[0030] In one embodiment of the multiple sample analysis method according to the present invention, the method includes a first analysis step of performing a first chromatography analysis using a photodiode array under conditions capable of separating a plurality of components contained in at least one sample from one another to obtain a three-dimensional chromatogram of the at least one sample, and extracting spectral data of each of the plurality of components contained in the at least one sample from the three-dimensional chromatogram of the at least one sample; a second analysis step of performing a second chromatography analysis using a photodiode array under conditions capable of obtaining a three-dimensional chromatogram of another sample having the same main component as the at least one sample, thereby obtaining a three-dimensional chromatogram of the other sample; and a peak separation step of applying a peak separation process based on the spectral data extracted in the first analysis step to the three-dimensional chromatogram of the other sample obtained in the second analysis step, thereby obtaining peak separation data for the other sample in which peaks of a plurality of components contained in the other sample are separated from one another.

[0031] In a first aspect of the above embodiment, the first analytical column used in the first chromatographic analysis and the second analytical column used in the second chromatographic analysis are different from each other in inner diameter, total length, and / or packing material. For example, in the first chromatographic analysis, a relatively expensive analytical column can be used as the first analytical column to obtain high peak separation, and in the second chromatographic analysis, an analytical column less expensive than the first analytical column can be used. This can reduce the cost required to analyze all of the multiple samples.

[0032] In a second aspect of the above embodiment, a mobile phase flow rate in the second chromatographic analysis is greater than a mobile phase flow rate in the first chromatographic analysis. This second aspect can be combined with the first aspect.

[0033] In the third aspect of the above embodiment, when there are two or more samples that have a common main component, the first analysis step is performed on one of the two or more samples to extract spectral data of each of the components contained in the one sample, the second analysis step is performed on the remaining samples of the two or more samples to obtain a three-dimensional chromatogram for each of the remaining samples, and the peak separation step is performed on the three-dimensional chromatogram for each of the remaining samples to obtain peak separation data for each of the remaining samples. With this aspect, the first chromatographic analysis, which requires a long time for analysis, is performed only on one sample, and the second chromatographic analysis, which is completed in a relatively short time, is performed on the remaining samples, so that the time required to complete the analysis of all samples can be significantly reduced. This third aspect can be combined with the first aspect and / or the second aspect.

[0034] In a fourth aspect of the above embodiment, the first chromatographic analysis and the second chromatographic analysis are liquid chromatographic analyses. Note that the "chromatographic analysis" in the present invention can include not only liquid chromatographic analysis but also gas chromatographic analysis. This fourth aspect can be combined with the first, second and / or third aspects.

[0035] In a fifth aspect of the above embodiment, the peak separation process uses an algorithm that estimates a peak of each component by fitting a model function, or an algorithm that mathematically estimates a peak of each component by matrix decomposition without using the model function. This fifth aspect can be combined with the first, second, third, and / or fourth aspects. [Explanation of symbols]

[0036] 2. Liquid delivery pump 4 Injectors 6 Separation column 8. PDA Detector 10. Oven 12 Processing Unit

Claims

1. a first analysis step of performing a first chromatographic analysis using a photodiode array for at least one sample under conditions capable of separating a plurality of components contained in the at least one sample from each other to obtain a three-dimensional chromatogram of the at least one sample, and extracting spectral data of each of the plurality of components contained in the at least one sample from the three-dimensional chromatogram of the at least one sample; a second analysis step of acquiring a three-dimensional chromatogram of another sample having the same main component as the at least one sample by performing a second chromatographic analysis using a photodiode array under conditions that allow a three-dimensional chromatogram to be acquired in a shorter time than the first chromatographic analysis; a peak separation step of acquiring peak separation data for the other sample, in which peaks of a plurality of components contained in the other sample are separated from one another, by applying a peak separation process based on the spectral data extracted in the first analysis step to the three-dimensional chromatogram of the other sample acquired in the second analysis step.

2. The multiple sample analysis method according to claim 1 , wherein a first analytical column used in the first chromatographic analysis and a second analytical column used in the second chromatographic analysis have different inner diameters, total lengths, and / or packing materials.

3. The multiple sample analysis method according to claim 1 or 2, wherein a mobile phase flow rate in the second chromatographic analysis is greater than a mobile phase flow rate in the first chromatographic analysis.

4. In the case where there are two or more samples that share a common principal component, performing the first analysis step on one sample of the two or more samples to extract spectral data of each of a plurality of components contained in the one sample; 4. The multiple sample analysis method according to claim 1, further comprising: performing the second analysis step on remaining samples of the two or more samples to obtain a three-dimensional chromatogram for each of the remaining samples; and performing the peak separation step on the obtained three-dimensional chromatogram for each of the remaining samples to obtain peak separation data for each of the remaining samples.

5. The multiple sample analysis method according to claim 1 , wherein the first chromatographic analysis and the second chromatographic analysis are liquid chromatographic analyses.

6. The multiple sample analysis method according to any one of claims 1 to 5, wherein the peak separation process uses an algorithm that estimates the peak of each component by fitting a model function, or an algorithm that mathematically estimates the peak of each component by matrix decomposition without using the model function.

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