Back to results
US 5,670,379 AGranted
Chromatograph system and method of use
AssigneesHitachi, Ltd., Hitachi Instruments Engineering Co., Ltd.
InventorsMasahito Ito, Junkichi Miura, Yoshio Fujii, Hiroshi Satake, Mitsuo Ito, Fuminori Umesato, deceased
Life of this patent
Estimating the term…
Abstract
A chromatograph system with improved automation is provided. In the chromatograph system of one embodiment, a regression line is set between retention times of predetermined peaks measured at each run in the past for a standard sample having known components. Referring to this regression line, the peak identifying condition, i.e., time window, is corrected. In another embodiment, there is provided a chromatograph apparatus having a function of estimating a limited life time of a system component. The analyzed results of the chromatograph system can thus be improved.
Claims29
A method for automatically correcting a measurement condition of a chromatograph system comprising steps of:
- a) chromatographically separating and measuring a plurality of runs of samples with the chromatograph system, each run of samples including, first a standard sample followed by unknown samples, to obtain a chromatogram of each of said samples, said chromatogram of each sample having a main peak and a subsidiary peak, said main peak appearing within a first time window defined by a first retention time and a first allowable width, and said subsidiary peak appearing within a second time window defined by a second retention time which is represented by a linear function of said first retention time of said main peak and a second allowable width;
- b) determining a main retention time of said main peak and a subsidiary retention time of said subsidiary peak of each sample;
- c) setting a regression line between points each represented by the main retention time on an abscissa and by the subsidiary retention time on an ordinate, for the samples of at least one of said runs;
- d) basing said first and second time windows for each of said plurality of runs on a set of preceding runs;
- and
- d) correcting said linear function by fitting said linear function to said regression line so that said second time window is updated.
3 more elements
A method for measuring a chromatograph of samples including glycated hemoglobin comprising steps of:
- a) chromatographically separating and measuring a plurality of runs of samples with the chromatograph, each run of samples including, first a standard sample followed by unknown samples, to obtain a chromatogram of each of said samples, said chromatogram of each sample having a main peak corresponding to a component A.sub.1c of the glycated hemoglobin and a subsidiary peak corresponding to at least one of components of F, 1-A.sub.1c and A.sub.1b, said main peak appearing within a first time window defined by a first retention time and a first allowable width, and said subsidiary peak appearing within a second time window defined by a second retention time which is represented by a linear function of said first retention time of said main peak and a second allowable width;
- b) determining a main retention time of said main peak and a subsidiary retention time of said subsidiary peak of each sample;
- c) setting a regression line between points each represented by the main retention time on an abscissa and by the subsidiary retention time on an ordinate, for the samples of at least one of said runs;
- d) basing said first and second time windows for each of said plurality of runs on a set of preceding runs;
- e) correcting said linear function by fitting said linear function to said regression line so that said second time window is updated and
- f) obtaining chromatograms of subsequent ones of said samples by employing the second time window updated.
3 more elements
A chromatograph system, comprising:
- a) a measuring column, having a pressure, to which samples to be measured may be supplied;
- b) means for analyzing a number of samples supplied to said column to obtain a chromatogram for each sample, said chromatograph including a retention time and a peak width for each sample measured;
- c) means for monitoring at least one monitored parameter selected from a group consisting of said pressure of said column, said retention times and said peak widths;
- d) first means for storing a function based on a change in said at least one parameter and said number of said samples analyzed;
- e) second means for storing a reference parameter at which said column should be changed;
- f) means for correcting said function to fit a set of said monitored parameters to said function;
- g) means for calculating a number of samples which can be analyzed before said at least one parameter becomes said reference parameter by referring to the monitored parameters and the function corrected;
- and
- h) means for indicating said calculated number of samples.
6 more elements
A chromatograph system, comprising:
- a) means for analyzing a sample in a column to obtain a chromatogram;
- b) means for monitoring a pressure (P) of said column and a number (S.sub.0) of samples analyzed;
- c) means for storing an upper limit pressure (P.sub.max) of said column at which said column should be changed;
- d) means for obtaining a first order differential value (dP/dS) and a second order differential value (d.sup.2 P/dS.sup.2);
- e) means for calculating a number (S.sub.max) of samples at which a pressure of said column becomes to said upper limit pressure (P.sub.max) in accordance with the following formula,
- P.sub.max =P(S.sub.0)+(dP/dS).sub.S=S.sbsb.0 (S.sub.max -S.sub.0)+k(d.sup.2 P/dS.sup.2).sub.S=S.sbsb.0 (S.sub.max -S.sub.0).sup.2
- wherein k is a constant;
- and
- f) means for indicating said number (S.sub.max) of samples thus calculated or a difference between said number (S.sub.max) calculated and said number (S.sub.0) monitored.
6 more elements
A method for measuring a chromatograph of a sample, comprising steps of:
- a) analyzing a number of samples supplied to a column, having a pressure, to obtain a chromatogram for each sample, said chromatograph including a retention time and a peak width for each sample measured;
- b) monitoring at least one monitored parameter selected from a group consisting of said pressure of said column, said retention times and said peak widths;
- c) storing a function based on a change in said at least one parameter and said number of said samples analyzed;
- d) storing a reference parameter at which said column should be changed;
- e) correcting said function to fit a set of said monitored parameters to said function;
- f) calculating a number of samples which can be analyzed before said at least one parameter becomes said reference parameter by referring to the monitored parameters and the function corrected;
- and
- g) indicating said calculated number of samples.
5 more elements
A method for measuring a chromatograph of a sample, comprising steps of:
- a) analyzing a sample to obtain a chromatogram;
- b) monitoring a pressure (P) of a column and a number (S.sub.0) of samples analyzed;
- c) storing an upper limit pressure (P.sub.max) of said column at which said column should be changed;
- d) obtaining a first order differential value (dP/dS) and a second order differential value (d.sup.2 P/dS.sup.2);
- e) calculating a number (S.sub.max) of samples at which a pressure of said column becomes to said upper limit pressure (P.sub.max) in accordance with the following formula,
- P.sub.max =P(S.sub.0)+(dP/dS).sub.S=S.sbsb.0 (S.sub.max -S.sub.0)+k(d.sup.2 P/dS.sup.2).sub.S=S.sbsb.0 (S.sub.max -S.sub.0).sup.2
- wherein k is a constant;
- and
- f) indicating said number (S.sub.max) of samples thus calculated or a difference between said number (S.sub.max) calculated and said number (S.sub.0) monitored.
6 more elements
A chromatograph system comprising:
- a chromatographic column for separating a sample to obtain a chromatogram having a plurality of peaks, including a first peak and a second peak;
- means for storing at least past information relating to said first peak and past information relating to said second peak;
- means for correlating between said past information relating to said first peak and said past information relating to said second peak;
- means for renewing said correlation based on successively obtained information of said first peak and successively obtained information of said second peak;
- and
- means for obtaining information relating to one of said plurality of peaks from detected information relating to another one of said plurality of peaks based on said correlation.
3 more elements
A method for obtaining a chromatogram with a plurality of peaks, including a first peak and a second peak by separating in time a sample through a column, comprising steps of:
- storing at least past information relating to said first peak and past information relating to said second peak;
- correlating between said past information relating to said first peak and said past information relating to said second peak;
- renewing said correlation based on successively obtained information of said first peak and successively obtained information of aid second peak;
- and
- obtaining information relating to one of said plurality of peaks from detected information relating to another one of said plurality of peaks based on said correlation.
2 more elements
Dependencies are inferred from the claim text.