Shimadzu Corporation

Yasuhiro Mito

Toshinobu Yanagisawa

Kenichi Mishima

Etsuho Kamata

Hiroshi Miura

Akira Noda

Katsuhiro Nakagawa

Hideo Iwasaki

Hideki Minegishi

A chromatogram data processing system having an impurity detector including a differential chromatogram creator, a purity curve creator and a determiner. The differential chromatogram creator calculates a differential coefficient of an absorbance spectrum with respect to wavelength at a local maximum or local minimum absorption wavelength of the target component, and creates a differential chromatogram which shows a temporal change of the differential coefficient. The purity curve creator creates a purity curve which shows a temporal change of the difference between the degree of similarity of a spectrum on the target peak to a reference spectrum and a threshold of the degree of similarity which is determined taking into account the influence of noise components. The differential chromatogram and the purity curve are displayed on a display unit in a superposed form on a wavelength chromatogram created by a wavelength chromatogram creator.

Chromatogram data processing system

A system for creating a chromatogram based on a temporal change of a spectrum obtained within a predetermined wavelength range including a target wavelength, the system including a post-correction chromatogram display section for displaying a post-correction chromatogram obtained by multiplying a chromatogram at the designated wavelength by a sensitivity factor obtained by dividing the intensity of the designated-time spectrum at the target wavelength by the intensity of the designated-time spectrum at the designated wavelength, and for changing the display to a post-correction chromatogram corresponding to the latest values of the designated time point and the designated wavelength when one or both of the designated time point and the designated wavelength are changed.

Data processing system and data processing method for chromatograph

Regarding a chromatogram data processing device configured to process three-dimensional chromatogram data collected on a target sample in which dimensions are made up of time, wavelength, and absorbance, and the chromatogram data processing device includes a differential spectrum generating means configured to generate a differential spectrum that represents a change in a wavelength differential coefficient, which is a differential coefficient in a wavelength direction in a predetermined wavelength range, based on the three-dimensional chromatogram data, with respect to an absorbance spectrum representing a relation of the wavelength and the absorbance at each time in an entire temporal range or a predetermined temporal range, and a determination means configured to determine whether or not one or plural other components are included in a peak of a target component, based on a temporal change in a waveform of the differential spectrum, so that the determination on whether or not a target sample includes impurities can be performed with high accuracy without the requirement of complicated computation processing.

Chromatogram data processing device and processing method

For vector A which expresses an absorption spectrum of a target component, vector F orthogonal to vector A is designated as a filter for extracting an impurity superposed on the target component on a chromatogram. For vector I which expresses a measured spectrum obtained by a chromatographic analysis performed on a sample, the inner product of vectors I and F is defined as an index value u of the amount of impurity. If an impurity is present, a peak-like waveform appears on a graph which shows a temporal change in the index value u for the measured spectrum obtained at each point in time of the measurement. By detecting this waveform, the presence or absence of the impurity can be correctly determined. The direction of vector F may be determined so that, when vector B which expresses a spectrum of the impurity is decomposed into vector Ba parallel to vector A and vector Bo orthogonal to vector A, vector F becomes nearly parallel to vector Bo (i.e. the cosine similarity index is maximized).

A data processing system for a chromatograph has an impurity detector including a differential chromatogram creator and a determining section. The differential chromatogram creator calculates a wavelength differential coefficient by differentiating an absorbance spectrum with respect to the wavelength at each point in time of the measurement and creates a differential chromatogram which shows a temporal change in the wavelength differential coefficient. Based on a shape of the thus created differential chromatogram, the determining section determines whether or not a peak of a target component contains an impurity. By this method, whether or not the peak of the target component contains an impurity can be determined with high accuracy, without requiring complex calculations.

System and method for processing chromatogram data

There are provided a data processing device for chromatograph and a data processing method for chromatograph which allow a peak to be desirably checked. A peak (correction target peak (P)) whose intensity exceeds a predetermined threshold in a chromatogram at a target wavelength (&#x3bb;) is corrected based on correction reference values (height (H) and area (A) of a peak (P)) and a sensitivity coefficient (R=I/I), and the chromatogram after correction is displayed or printed. Therefore, even if the correction target peak (P) is saturated, display or printing may be performed in a state where correction has been performed so that the chromatogram at the peak (P) is not cut off in the middle. Accordingly, at the time of display or printing of the chromatogram, a fine peak may be prevented from becoming too small, and also the correction target peak (P) may be prevented from being cut off in the middle, and thus the peaks may be desirably checked.

Data processing device for chromatograph and data processing method for chromatograph

A preparative separation chromatograph system having a column for temporally separating components in a sample and for discharging an eluate fluid with the components, a detector for obtaining an absorbance spectrum of the eluate fluid, and a fraction collector for continuously creating a chromatogram. The system further includes: a peak section determiner; a differential value determiner for calculating a differential spectrum value and for determining whether or not the absolute value of the differential spectrum value is equal to or less than a predetermined value; and a fraction collector controller for controlling the fraction collector so as to fractionate the eluate fluid during a period of time for which it is determined that the chromatogram peak of the target component is present and for which it is also determined the absolute value of the differential spectrum value is equal to or less than the predetermined value.

Preparative separation chromatograph system

A data processing system for a chromatograph including a standard sample data storage section; a standard sample sensitivity factor calculator; a post-correction standard sample chromatogram strength calculator; a specific designated retention time and specific designated wavelength setter; a measurement sample data storage section; a measurement sample sensitivity factor calculator; and a post-correction measurement sample chromatogram creator.

Data processing system and method for chromatograph

An apparatus and a method for chromatogram peak purity determination are provided, where the chromatogram's dimensions consist of retention time, wavelength and absorbance. The apparatus or method accumulates, at each retention time, absorbance in the wavelength direction for all or a part of a wavelength range in a predetermined retention time range; extracts a plurality of groups where, for each group, the absorbance accumulation value is the same for one point on a rising slope and one point on a falling slope regarding a peak that exists on a chromatogram that is prepared based on a 2-dimensional data whose dimensions are absorbance accumulation value and retention time; calculates similarities between absorption spectrum pattern at one point on the rising slope and at one point on the falling slope for each group; and determines from the plurality of groups, whether the peak consists of a single component based on similarity.

Chromatogram peak purity determination apparatus

In a system of this invention, an inquiring computer supplies a host computer with inquiry information indicated open or closed to third parties. The host computer applies inquiry information indicated open to a wide range of inquiring and answering computers, but does not apply inquiry information indicated closed to third party inquiring computers. Inquiry information indicated closed is applied to a small range including only the inquiring computer having inputted the inquiry information and answering computers. When answer search information is transmitted from the inquiring computer to the host computer, answer information supplied from an answering computer may be received through communication lines. Thus, the answer information for the inquiry information may be obtained efficiently while taking the security protection for the inquiry information presenting party into account.

Scientific information inquiry-answer system, and a host computer and an inquiring computer therefor

An uploading computer, a host computer and a viewing computer are interconnected through communication lines. The host computer hierarchizes software information received from the uploading computer by field, category and software product to be stored in software information memory. In response to search information inputted from the viewing computer, the software information is displayed as search results on the viewing computer. The software information hierarchized in the order of field, category and software product is retrieved quickly and displayed immediately to browsed efficiently.

Scientific information viewing system, and a host computer and a viewing computer therefor

A detection signal from a multi-wavelength detector provided in a liquid chromatograph is stored in a data storage part, and a chromatogram is formed from the stored data with respect to a specific wavelength, to detect a peak from the chromatogram. The spectrum at a top of the peak to be identified or a known spectrum of a component to be identified is used as a reference spectrum, to calculate the degree of coincidence between the spectrum at each position of the chromatogram peak and the reference spectrum as fraction purity at each position of the chromatogram peak. The calculated fraction purity values are classified in colors, for example, and displayed on a display part. Thus, it is possible to readily decide whether the measured peak consists of a single component or at least two components, and which time range consists of a single component.

Fraction purity measuring apparatus for chromatogram peak

It is judged whether a part of a peak section of a chromatogram corresponding to a component of a sample is pure by comparing a similarity value of the absorbance spectrum of the part to a threshold value. The similarity value r and the threshold value t are calculated as follows. a) A series of absorbance spectra of a sample effluent from a column of the chromatograph are obtained repeatedly at a plurality of time points of short intervals. An absorbance spectrum is composed of a set of absorbance data with respect to wavelengths of light passing through the sample. b) A chromatogram of the sample is constructed using the series of absorbance spectra. c) A peak section including an object component of the sample is detected in the chromatogram. d) A similarity value is then calculated as a cosine of the angle between an absorbance spectrum vector and a standard spectrum vector. e) The threshold value is calculated by a cosine of the angle between two outermost tangential lines of an n-dimensional sphere centering an end of the absorbance spectrum vector and another n-dimensional sphere centering an end of the standard spectrum vector.

Apparatus for and method of determining purity of a peak of a peak of a

Spectrum images of chromatograph column effluent are formed on a photodiode array (7). The photodiode array (7) is scanned to produce plural detection data for predetermined plural wavelengths. The data are analytically processed and recorded to provide data ratios wherein the numerators are processed data from individual wavelengths, and the denominator in each of the ratios is the square root of the sum of the square of the processed data for the individual wavelengths. A plot of ratios versus time provides a curve which indicates completeness of chromatographic separation.

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Kyotanabe, Japan

Yasuhiro Mito