US4557601A
Expired / Lapsed
US
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Elimination of ghost component in flow injection analysis method
Assignee: Hitachi Ltd
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Filing: 1982-09-22
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Granted: 1985-12-10
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Expires: 2002-09-22
Abstract
Abstract In a flow injection analysis method of injecting a predetermined amount of a sample into a continuous flow of a carrier solution and introducing a reaction zone of the sample and the carrier solution into a flow cell, signals representative of the respective absorptions of the reaction zone for a plurality of wavelengths are produced when the reaction zone is passing through the flow cell. The signals are subjected to an at least two-wavelength processing or differentiation processing, thereby providing a desired absorbance of a substance of interest for analysis free of the influence of a ghost component.
Inventors
- 👤 Tadafumi Kuroishi
- 👤 Kazuo Yasuda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 02:02
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/75; G01N21/17; G01N21/25; G01N21/31; G01N21/314; G01N21/84; G01N21/85
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
214 words
A flow injection analysis method comprising: a first step of injecting a predetermined amount of a sample into a continuous flow of a carrier solution to form a sample zone therein; a second step of bringing said sample zone into a flow cell which is irradiated with light from a light source, wherein a combination of a light dispersion means and a photodetector means is disposed behind said flow cell for spectrophotometric measurement; a third step of separating light transmitted through said sample zone in said flow cell into monochromatic light components of different wavelengths by means of said light dispersion means; a fourth step of directing aaid monochromatic light components onto said photodetector means at a predetermined time to produce electric absorption signals which are representative of the respective absorptions of said sample zone at said predetermined time for a plurality of wavelengths of light within a predetermined wavelength range; and a fifth step of producing a difference between the value of a first one of said absorption signals associated with a preselected first wavelength which substantially gives a peak level of absorption and a value related to the value of a second one of said absorption signals associated with at least one preselected second wavelength which gives a smaller level of absorption.
Claim 2
Dependent Claim
214 words
A flow injection analysis method comprising: a first step of injecting a predetermined amount of a sample into a continuous flow of a carrier solution to form a sample zone therein; a second step of bringing said sample zone into a flow cell which is irradiated with light from a light source, wherein a combination of a light dispersion means and a photodetector means is disposed behind said flow cell for spectrophotometric measurement; a third step of separating light transmitted through said sample zone in said flow cell into monochromatic light components of different wavelengths by means of said light dispersion means; a fourth step of directing aaid monochromatic light components onto said photodetector means at a predetermined time to produce electric absorption signals which are representative of the respective absorptions of said sample zone at said predetermined time for a plurality of wavelengths of light within a predetermined wavelength range; and a fifth step of producing a difference between the value of a first one of said absorption signals associated with a preselected first wavelength which substantially gives a peak level of absorption and a value related to the value of a second one of said absorption signals associated with at least one preselected second wavelength which gives a smaller level of absorption.
Claim 3
Dependent Claim
46 words
A flow injection analysis method according to claim 1, wherein in said fifth step, one wavelength is selected as said second wavelength and the difference of A 1 -A 2 is produced, A 1 and A 2 being said first and second absorption signal values respectively.
Claim 4
Dependent Claim
74 words
A flow injection analysis method according to claim 1, wherein in said fifth step, two wavelengths λ 2 and λ 3 satisfying a relation of λ 2 >λ 1 >λ 3 and having their associated second absorption signal values A 2 and A 3 respectively, λ 1 being said first wavelength having the associated first absorption signal value A 1 , are selected as said second wavelength and the difference of ##EQU3## is produced.
Claim 5
Dependent Claim
36 words
A flow injection analysis method according to claim 3, wherein said second wavelengths λ 2 and λ 3 satisfy a relation of λ 2 -λ 1 =λ 1 -λ 3 and the difference ##EQU4## is produced.
Claim 6
Dependent Claim
36 words
A flow injection analysis method according to claim 1, wherein said carrier solution includes a reagent and said sample zone formed at said first step is a zone where the injected sample reacts with the reagent.
Claim 7
Dependent Claim
169 words
A flow injection analysis method comprising: a first step of injecting a predetermined amount of a sample into a continuous flow of a carrier solution to form a sample zone therein; a second step of bringing said sample zone into a flow cell which is irradiated with light from a light source, wherein a combination of a light dispersion means and a photodetector means is disposed behind said flow cell for spectrophotometric measurement; a third step of separating light transmitted through said sample zone in said flow cell into monochromatic light components of different wavelengths by means of said light dispersion means; a fourth step of directing said monochromatic light components onto said photodetector means at a predetermined time to produce electric absorption signals which are representative of the respective absorptions of said sample zone at a predetermined time for a plurality of wavelengths of light within a predetermined wavelength range; and a fifth step of differentiating said absorption signals with respect to wavelength to produce a derivative spectrum.
Claim 8
Dependent Claim
169 words
A flow injection analysis method comprising: a first step of injecting a predetermined amount of a sample into a continuous flow of a carrier solution to form a sample zone therein; a second step of bringing said sample zone into a flow cell which is irradiated with light from a light source, wherein a combination of a light dispersion means and a photodetector means is disposed behind said flow cell for spectrophotometric measurement; a third step of separating light transmitted through said sample zone in said flow cell into monochromatic light components of different wavelengths by means of said light dispersion means; a fourth step of directing said monochromatic light components onto said photodetector means at a predetermined time to produce electric absorption signals which are representative of the respective absorptions of said sample zone at a predetermined time for a plurality of wavelengths of light within a predetermined wavelength range; and a fifth step of differentiating said absorption signals with respect to wavelength to produce a derivative spectrum.
Claim 9
Dependent Claim
36 words
A flow injection analysis method according to claim 6, wherein said carrier solution includes a reagent and said sample zone formed at said first step is a zone where the injected sample reacts with the reagent.
Claim 10
Dependent Claim
27 words
A flow injection analysis method according to claim 6, wherein the differentiation in said fifth step is carried out once to produce a 1st order derivative spectrum.
Claim 11
Dependent Claim
27 words
A flow injection analysis method according to claim 6, wherein the differentiation in said fifth step is carried out twice to produce a 2nd order derivative spectrum.
References Cited (Backward Citations)
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