JPH0792432B2 - Automatic chemical analyzer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Industrial field of application) The present invention splits light transmitted through a reaction solution into multiple wavelengths and measures the absorbance corresponding to each wavelength to measure a plurality of items. The present invention relates to an automatic chemical analyzer for performing chemical analysis of.

(Prior Art) For example, serum collected from a human body is used as a sample, and a desired reagent that reacts with a specific component therein is reacted therewith, and the absorbance of light of a specific wavelength in the reaction solution is compared. 2. Description of the Related Art There is known an automatic chemical analyzer that detects the concentration of the specific component by measurement by a color method and uses it for diagnosis. FIG. 4 shows an outline of such an automatic chemical analyzer. For example, a reaction vessel 2 which is intermittently fed in a constant cycle in a direction indicated by an arrow by a drive source (not shown) is arranged in a circular constant temperature bath 1. A sample dispensing device 3 for dispensing a sample to be analyzed is placed in a reaction container 2 in an opposite position at a position A around the constant temperature bath 1, and a reaction is performed between the sample in a reaction container 2 in an opposite position at a position B. A reagent dispensing device 4 for dispensing the reagent to be used is disposed, and a stirrer 5 for stirring the reaction liquid of the sample and the reagent in the reaction container 2 at the opposite position is disposed at the position C. . Further, at a position D of the constant temperature bath 1 through which the reaction container 2 of the reaction solution sufficiently stirred passes, an absorbance measuring section 8 including a light source 6 and a photodetector 7 arranged with the reaction container 2 interposed is provided. A desired item is measured by injecting light into the reaction solution, measuring the amount of the light transmitted, and measuring the absorbance A ₀ corresponding to the specific wavelength λ ₀ on the absorption spectrum as shown in FIG. As described above, when performing a chemical analysis of a desired item with an automatic chemical analysis device, recently, a photodiode array is used as a photodetector to split the light transmitted through the reaction solution into multiple wavelengths to obtain the absorbance corresponding to each wavelength. A multi-wavelength photometric system for measuring is established. FIG. 5 shows such a photometric system, in which the light emitted from the light source 6 enters the optical fiber 10a through the condenser lens 9 and is branched into a plurality of optical paths by the optical fiber 10a. , Is incident on the reaction container 2 via each optical path prism 11a. The light that has passed through the reaction liquid in the reaction container 2 is incident again on the optical fiber 10b via the prism 11b, and is then incident on the optical switch 12 that selectively allows incident light from a plurality of optical paths n to pass. One selected optical path is guided to the slit 14 via a pair of mirrors 13a and 13b,
It is incident on the diffraction grating 15. Incident light is split into multiple wavelengths by the diffraction grating 15, and light of each wavelength is detected as a current by a photodetector 16 including a photodiode array. The current detected in this way is guided to the amplifier and subsequent stages, and the absorbance is calculated for each wavelength by the CPU or the like. FIG. 6 shows the absorption spectrum thus obtained, and the corresponding absorbance A ₀ can be obtained by specifying the wavelength λ ₀ .

(Problems to be Solved by the Invention) By the way, in the conventional automatic chemical analyzer, in case of measuring the absorbance by multi-wavelength photometry, it is necessary to prepare a plurality of corresponding reaction vessels in order to measure a plurality of items. There is a problem of inefficiency. Further, when performing such a measurement, when the absorption spectrum of the measurement target at the specific wavelength for which the absorbance is to be measured is overlapped with the absorption spectrum of serum color such as chyle, the true absorption to be measured is the absorbance corresponding to the absorption due to this serum color. Since it is added, there is a problem that the measurement error becomes large.

FIGS. 7 (a) and 7 (b) show this state. As shown in FIG. 7 (a), chyle or the like occurs at a specific wavelength (first wavelength) λ ₁ on the absorption spectrum S ′ of the measurement object. When the absorption spectra S'of the serum color tone of the above exist, the absorption spectra S'to be measured are added by this amount due to the influence of the spectra S'and the apparent absorbance increases. , The absorption spectrum S is obtained. Therefore, the absorbance corresponding to the wavelength λ ₁ on each spectrum S, S ′, S ″ becomes A ₁ , A ′ ₁ , A ″ ₁ , respectively, and the true absorbance to be measured is A ′.
Even though it is ₁ , the wrong A ₁ will be measured. In order to prevent this adverse effect, as shown in FIG. 7 (b), the wavelength λ _c for correction is set at the position where the spectrum is distant by l from the specific wavelength λ ₁ , and the absorbance A corresponding to this λ _c is set. _{By finding c} , the difference in absorbance between these two wavelengths ΔA ′ = A ₁
Although correction is performed by obtaining −A _c , strictly speaking, the effect of serum color tone cannot be avoided because A ″ ₁ −A ″ _c causes an error. This is particularly the case when 1 is set to a large value when an assay with poor measurement sensitivity such as an immunoassay is performed, and this tendency becomes remarkable.

The present invention has been made in response to a situation such as an abnormality,
It is an object of the present invention to provide an automatic chemical analyzer that improves measurement efficiency and reduces the influence of serum color tone.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention relates to a sample dispensing means for dispensing a sample to be measured into a reaction container, and the reaction container to influence each other. Reagent dispensing means for dispensing a plurality of reagents not included, measuring means for injecting light into the reaction liquid of the sample and a plurality of reagents dispensed into the reaction container, and measuring transmitted light for each of a plurality of wavelengths, First and second at least corrections for photometric results of a plurality of specific wavelengths set corresponding to each of the plurality of reagents and one side of the specific wavelengths
The absorbance corresponding to each wavelength from the photometric results corresponding to the wavelength of, and based on them, the error due to the serum color tone is corrected based on the analysis means for analyzing the items corresponding to the plurality of reagents. To do.

(Operation) According to the present invention having the above configuration, a plurality of reagents that do not affect each other are dispensed into a reaction container in which a sample is dispensed, light is incident on the reaction solution, and transmitted light is transmitted at each of a plurality of wavelengths. And a photometric result of a plurality of specific wavelengths set corresponding to each of the plurality of reagents and a photometric result corresponding to at least the first and second wavelengths for correction set on one side of the specific wavelengths. It is possible to obtain the absorbance corresponding to each wavelength from the result, correct the error due to the serum color tone based on the absorbance, and simultaneously analyze a plurality of items corresponding to a plurality of reagents.

Embodiments Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of an automatic chemical analyzer according to the present invention, which is a photodetector as a measuring means for measuring transmitted light.
Reference numeral 16 is a photodiode array for detecting multiple wavelengths dispersed by the diffraction grating 15 as shown in FIG. 5. The detected currents are output to the amplifiers 17 and converted into voltages, respectively, and then the multiplexer 18 Only one wavelength is selected by and added to the A / D converter 19. The A / D converter 19 converts an input signal into a digital signal, and this digital signal is passed through an interface 20 to a CPU as an analysis means.
(Central processing element) 21.

Based on the digital signal, the CPU 21 sets at least λ ₁ , λ _c , and λ ₂ on the spectrum to be measured as shown in FIG. ₂ , and combines the absorbances at each of these wavelengths to perform two arithmetic operations. It has the function of measuring D ₁ and D ₂ . Of these, λ ₁ and λ ₂ are two items D ₁ and D ₂
Is set to a position corresponding to, and λ _c is set to a position where there is little change in absorbance between λ ₁ and λ ₂ . That is, λ ₁ , λ _c
The absorbances A ₁ and A _c are obtained from the above, the absorbance corresponding to the item D ₁ is measured, and the absorbances A ₂ and A _c are obtained from λ ₂ and λ _c , and the item D ₂ is obtained.
The absorbance corresponding to is measured. The absorbance data processed by the CPU 21 is stored in the memory incorporated therein.

Further, when there is an absorption spectrum S'to be measured and the apparent absorption spectrum S overlaps with the absorption spectrum S "of the serum color tone of milky milk etc. and the apparent absorption spectrum is S, the CPU 21 corrects as shown in FIG. The first wavelength λ _c1 and the second wavelength λ _c2 for correction are set to one side of the wavelength λ ₁ corresponding to the measurement item D ₁ , and these wavelengths λ ₁ , λ _c1 , and λ _c2 are set. It has a function of correcting the absorbance from the corresponding absorbance based on the following equation: The second wavelength λ _c2 for the correction is such that the absorbance of the absorption spectrum S ′ of the measurement target is reduced to approximately O. Selected to the position.

As shown in FIG. 3, the absorption spectrum S ′ of the measurement object, the absorption spectrum S ″ of the serum color tone, the apparent absorption spectrum S
, The absorbance corresponding to the wavelength λ ₁ is A ₁ , A ′ ₁ , A ″
_1. Absorbances corresponding to the first wavelength λ _c1 for correction are A _c1 , A ′ _c1 and A ″ _c1 , respectively, and absorbances corresponding to the second wavelength λ _c2 for correction are A _c2 and A ′, respectively. _{If c2} , A ″ _c2 , then the following equation holds.

A " ₁ = A ₁ -A ' ₁ A" _c1 = A _c1 -A' _c1 A " _c2 = A _c2 -A ' _c2 A _c2 = A" _{c2 A'c2} = 0 Also, k ₁ = A " ₁ / _{a "c2 k 2 = a"} c1 / a: " coefficient for correcting the _1, k _2: λ _c2 absorbance a for" the _{c2 'c2} k ₁ absorbance a of lambda _c2 "absorbance a of lambda _{1 c2} of lambda _c1 From the coefficient for correcting the absorbance A ″ _c1 and the apparent absorption spectrum S at λ ₁ , λ _c1 , and λ _c2 , the absorbance difference ΔA ″ can be obtained by the following equation.

ΔA ″ = (A ₁ −A _c1 ) − {(k ₁ −1) A _c2 − (k ₂ −1) A
_c2 } (1) The CPU 21 corrects the calculation based on the absorbance difference ΔA ″.

At this time, in the reaction container 2, in addition to the sample to be analyzed, the first reagent and the second item corresponding to the _first item D ₁ to be measured.
The second reagent corresponding to D ₂ is mixed, and those which can coexist without affecting each other are selected. These first and second items D ₁ and D ₂ can be measured simultaneously from the same reaction vessel by specifying different wavelengths λ ₁ and λ ₂ .

The operation panel 22 is provided with a keyboard and is used for inputting data required for analysis, and is used, for example, for inputting a wavelength corresponding to a measurement item. The display 23 is composed of a well-known CRT or the like and displays the results calculated by the CPU 21 based on the data input from the operation panel 22, and these display results can be output from the printer 24.

The operation of this embodiment will be described below.

In addition to the sample to be analyzed in the reaction container 2, a first reagent corresponding to the _first item D ₁ to be measured and a second reagent corresponding to the second item D ₂ are mixed and then added to these reaction solutions. The light transmitted by the light from the light source 6 is incident on the diffraction grating 15 through the optical switch 12 and is split into multiple wavelengths. After the current corresponding to each wavelength is detected by the photodetector 16, necessary processing is performed and each absorbance is calculated by the CPU 21 and stored in the memory. At this time, wavelength data set via the operation panel 22, for example, the wavelength λ ₁ corresponding to the _first item D ₁ , the wavelength λ ₂ corresponding to the _second item D ₂ , and λ ₁ ,
Three wavelengths λ _c for correction are set at positions where they are located between λ ₂ and have little change in absorbance. This makes CPU21
As shown in FIG. 2, the absorbance corresponding to item D ₁ is measured from the absorbances A ₁ and A _c of λ ₁ and λ _c , and at the same time, the absorbances A ₂ and A _{c of} λ ₂ and λ _c are changed to item D ₂ . Measure the corresponding absorbance. These measurement results are displayed on the display 23 and output from the printer 24 as needed.

Therefore, the first item D ₁ and the second item from the same reaction vessel
Since D ₂ can be measured at the same time, the measurement efficiency can be improved, and the number of reaction vessels can be reduced when measuring the same number of items. Further, the wavelengths to be set are not limited to three wavelengths and may be four wavelengths or more.

Next, the absorption spectrum S'of the measurement object at a specific wavelength (wavelength to be measured) is added to the spectrum S "of serum color tone such as chyle.
, The λ ₁ , as shown in Fig. 3,
From the absorbances A ₁ , A _c1 and A _{c2 of} λ _c1 and λ _c2, the CPU 21 obtains the absorbance difference ΔA ″ according to the above equation (1) and corrects the calculation accordingly. Therefore, the absorption spectrum S ′ of the measurement target is obtained.
Since it is possible to obtain the true absorbance based on, it is possible to reduce the influence of the serum color tone. The serum color tone can be similarly applied to hemolysis, jaundice, etc. in addition to chyle.

[Effects of the Invention] As described above, according to the present invention, a sample is reacted with a plurality of reagents that do not affect each other, and the transmitted light of a plurality of wavelengths of the reaction solution is measured to support a plurality of reagents. Determining the absorbance corresponding to each wavelength from the photometric result of the specific wavelength and the photometric result corresponding to at least the first and second wavelengths for correction set on one side of the specific wavelength,
Based on them, the error due to the serum color tone was corrected to analyze the items corresponding to a plurality of reagents, so that it is possible to measure a plurality of items in the same reaction container at the same time, so that the measurement efficiency can be improved, Moreover, since the correction is performed to eliminate the error due to the serum color tone, the analysis can be performed while reducing the influence of the serum color tone.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the automatic chemical analyzer of the present invention, FIGS. 2 and 3 are absorbance characteristic diagrams for explaining the operation of the apparatus of the present embodiment, and FIG. 4 is an example of the automatic chemical analyzer. FIG. 5 is a schematic diagram showing a configuration example, FIG. 5 is a configuration diagram showing a multi-wavelength measuring system of an automatic chemical analyzer, FIG. 6 is a characteristic diagram showing absorbance measurement, and FIGS. 7 (a) and 7 (b) are according to serum color tone. It is a characteristic view explaining influence on absorbance measurement. 2 ... Reaction vessel, 12 ... Optical switch, 15 ... Diffraction grating,
16 ... Photo detector, 21 ... CPU (central processing unit).

 ─────────────────────────────────────────────────── --- Continuation of the front page (56) Reference JP-A-54-84781 (JP, A) JP-A-48-94492 (JP, A) JP-A-57-106843 (JP, A) JP-A-63- 66466 (JP, A) JP 63-129998 (JP, A) JP 63-148166 (JP, A)

Claims (1)

[Claims] 1. A sample dispensing means for dispensing a sample to be measured into a reaction container, a reagent dispensing means for dispensing a plurality of reagents that do not affect each other into the reaction container, and a reagent dispensed into the reaction container. In addition, light is incident on the reaction liquid of the sample and a plurality of reagents, and a measuring unit that measures transmitted light for each of a plurality of wavelengths, and a photometric result of a plurality of specific wavelengths set corresponding to each of the plurality of reagents and The absorbances corresponding to the respective wavelengths are obtained from the photometric results corresponding to at least the first and second wavelengths for correction set on one side of the specific wavelength, and the error due to the serum color tone is corrected based on the absorbances. An automatic chemical analysis device comprising: an analysis unit that analyzes items corresponding to the plurality of reagents.