JPH0526144B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention utilizes a reaction line for colorimetry also for electrodes, dispenses a sample, etc. in the same operation, and selectively adds electrolyte according to the analysis item. The present invention relates to an automatic chemical analyzer that can also perform analysis.

[Technical background of the invention and its problems]

As is well known, an automatic chemical analyzer has a large number of reaction tubes arranged in a reaction line on an endless belt, and dispenses a certain amount of sample taken by a patient from a certain set point, and another. A specific reagent according to the analytical measurement item is dispensed from a location, this mixed solution is reacted, and this is analyzed by colorimetric or electrochemical analysis during the reaction (rate method) or after the reaction is completed (end method). This is done automatically.

By the way, in conventional automatic chemical analyzers, separate reaction lines for colorimetric analysis and electrode lines for electrochemical analysis are used, and predetermined lines are used for each on separate lines. Samples and reagents were being dispensed. This results in an increase in the size and cost of the device, problems with the location of its installation, and complication in the configuration and operation of the device.

On the other hand, in an electrolyte analyzer using an ion-selective electrode, the influence of the sample temperature on the ion electrode causes a large measurement error. Conventionally, therefore, the accuracy of measurements has been ensured by preheating the sample or by measuring the sample temperature and making temperature corrections.

However, when a sample is preheated, a temperature difference occurs between the preheat section and the electrode section, or a temperature change of the sample occurs while leaving the preheat section and reaching the electrode section. Also,
For temperature-corrected data, the correction calculation becomes complicated.

[Purpose of the invention]

The present invention was made based on the above circumstances, and
An object of the present invention is to provide an automatic chemical analyzer that can prevent the device from becoming larger and more complex by incorporating an electrolyte analyzer using an ion-selective electrode into a colorimetric reaction line, and can accurately measure electrolytes. purpose.

[Summary of the invention]

To achieve the above object, an automatic chemical analyzer according to the present invention is an automatic chemical analyzer capable of colorimetric analysis by photometrically measuring a liquid to be measured contained in reaction tubes arranged in a row. a suction nozzle that is movable up and down on the reaction tube array to selectively suck the liquid to be measured from the reaction tube array in which the liquid is stored; a pump connected to the suction nozzle via a pipe line; It is equipped with an electrode device that is installed in this conduit and integrates a constant temperature part that heats the solution to be measured to a predetermined temperature and an electrode part that measures the electrolyte of the solution to be measured heated by this constant temperature part. It is characterized in that it can be switched so that both or either one of the electrolyte items can be measured.

[Embodiments of the invention]

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

Fig. 1 is a schematic explanatory diagram showing an embodiment of the automatic chemical analyzer according to the invention, Fig. 2 is an explanatory diagram showing the electrolyte analyzer which is the main part of the present invention, and Fig. 3 is an explanatory diagram of the electrolyte analyzer. The cross-sectional views in FIGS. 4a, b, c, d, and e showing our electrode device are explanatory diagrams showing the operation up to the time of measurement with the electrodes.

In FIG. 1, 1 is an endless reaction line that sequentially moves a large number of reaction tubes 2 in the X direction. Further, 3 indicates a sample dispensing device having a sampling nozzle for dispensing a sample (for example, serum, etc.), 4 indicates a reagent dispensing device having a reagent nozzle for dispensing a reagent, and 5 The reference numeral 6 indicates a photometry section that performs colorimetric analysis by measuring light after mixing and reacting the sample and reagent, and the reference numeral 6 indicates a cleaning section that cleans the reaction tube 2 after photometry. It is arranged along line 1.

10 is an electrolyte analyzer having a suction nozzle arranged along the reaction line 1;
As shown in FIG. 2, this electrolyte analyzer 10 includes a suction nozzle 11 for suctioning the liquid in the reaction tube 2, a suction pump 12 for sucking and discharging, and a suction nozzle 11 and the suction pump 12 connected together. It consists of a tube 13 and an electrode device 14 interposed in the middle of the tube 13. The suction nozzle 11 is equipped with a vertical movement mechanism 11a for selectively sucking only the reaction liquid in a predetermined reaction tube 2 moving on the reaction line 1.
Further, the electrode device 14 is connected to a heat block 14A around which the tube 13 is wound, as shown in FIG.
and an electrode section 1 for performing electrolyte measurement with an ion-selective electrode through the solution to be measured in the tube 13.
4B, and a heat insulating case 14C that houses a heat block 14A and an electrode section 14B. Furthermore, the second
In the figure, 15 is a three-way pot for switching between suction and discharge, and 16 is a drainage tube.

Next, the operation of the automatic chemical analyzer configured as above will be explained.

A sample is dispensed by a sample dispensing device 3 into a reaction tube 2 that moves sequentially through a reaction line 1, a reagent is dispensed by a reagent dispensing device 4, the mixed liquid is reacted, and the reaction is carried out in a photometer 5. The reaction solution in tube 2 is photometered for colorimetric analysis. Reaction tube 2 after photometry
The dirt is washed away by the cleaning section 6, and the tube moves on the reaction line 1 again as a reaction tube for accommodating the reaction solution.

The reaction line 1 for colorimetric analysis described above is also used for electrolyte analysis based on the operation described below.
That is, a sample for electrolyte analysis, a calibration solution, and a reagent are selectively dispensed from a sample nozzle and a reagent nozzle into a reaction tube 2 that sequentially moves on a reaction line 1 according to a preset input. .
That is, first, a calibration solution stock solution is dispensed into the first reaction tube 2a using the sample dispensing device 3, and then a reagent is dispensed and diluted using the reagent dispensing device 4. This becomes the calibration solution for electrode calibration. Serum, which is a sample, is dispensed into the next reaction tube 2b using the sample dispensing device 3, and then a reagent is dispensed using the reagent dispensing device 4 to dilute the serum. This becomes the measurement solution to be analyzed. Similarly, the sample dispensing device 3 and the reagent dispensing device 4 are respectively used in the last reaction tube 2c to dispense the stock solution of the calibration solution and dilute it with the reagent. This becomes the electrode cleaning calibration solution. The above dispensing operation completes dispensing for one sample. The reagents used here are:
Calibration solution stock solution is a buffer solution for diluting serum 10 times.

In this way, only when the reaction tubes 2a, 2b, 2c containing electrode samples are stopped at the position of the suction nozzle 11 after sampling and dispensing for electrolyte analysis, the suction nozzle 11 is selectively moved up and down by the vertical movement mechanism 11a. The reaction solution in the reaction tube is sequentially sucked out. That is, as shown in FIG. 4a, first, the calibration solution A for electrode calibration (indicated by diagonal lines) that has entered the reaction tube 2a is sucked from the suction nozzle 11 by the suction pump 12, and then the calibration solution A for electrode calibration (indicated by diagonal lines) is sucked out from the suction nozzle 11 for a predetermined period of time. After (e.g. 18 seconds), as shown in Figure 4b,
The diluted serum B (indicated by diagonal lines) in the reaction tube 2b is sucked from the suction nozzle 11, and at this time, the calibration solution A for electrode calibration is transferred to the heat block 14.
It stops at A and is heated to a constant temperature. Then 18
Seconds later, as shown in FIG. 4c, the electrode cleaning calibration solution C (indicated by diagonal lines) that has entered the reaction tube 2c is sucked out from the suction nozzle 11, and the diluted serum B is transferred to the heat block 14A. The calibration solution A for electrode calibration is heated to a constant temperature.
moves to the electrode section 14B and is measured there. Further, after 18 seconds, as shown in FIG. 4d, the calibration liquid C for electrode cleaning is transferred to the heat block 14A by the suction operation of the suction pump 12 and heated to a constant temperature, and the diluted serum B moves to the electrode section 14B, where the electrolyte is measured. Finally, after 18 seconds, as shown in FIG. 4e, the electrode cleaning calibration solution C is transferred to the electrode part 14B by the suction pump 12, cleaning the electrode part 14B, and the next sample is measured. be prepared for. The calibration solution A for electrode calibration, the diluted serum B, and the calibration solution C for electrode cleaning, which have flowed into and out of the electrode section 14B in this way, are sequentially pumped by the suction pump 12 via the three-way tank 15. It is pushed out into the drainage tube 16. The length of the tube 13 from the suction nozzle 11 to the electrode section 14B is set so that it can hold two samples, and all of the operations described above are based on control signals from a control section (not shown). It is being done.

The liquid to be measured, which is kept at a constant temperature in the electrode device 14 in this way, is used as an ion-selective electrode.
Measurements can be performed according to the measurement items of Na ⁺ , K ⁺ , and Cl ^- .

Next, calculations in actual measurements will be explained with reference to FIGS. 5 to 7.

Two types of standard solutions are used during calibration: an abnormally low range concentration C _L and an abnormally high range concentration C _H in contrast to the calibration solution stock solution CN with a normal range concentration.
The response electromotive force at that time is as shown in Figure 5.
The potential gradient of the calibration curve is determined from ΔE _L and ΔE _H , which are each measured as a difference with respect to the electromotive force of the calibration solution, as shown in FIG. In other words, the potential gradient S is as follows:
Indicated by (1).

S=(△E _L −△E _H )/log (C _L /C _H )...(1) The electromotive force response when measuring a sample such as serum after cavitation is as shown in Figure 7. Measure the electromotive force difference ΔE between the calibration solution and the sample. Then, the unknown concentration Ci can be determined by the following equation (2) using S and ΔE determined during calibration.

Ci=CL・10 ⁽⁽ △ ^E- △ ^EL)/S) ...(2) In the above measurements, colorimetric tubes were placed before and after the three reaction tubes 2a, 2b, and 2c containing the electrode samples. The reaction tube 2 containing the sample is sequentially transferred on the reaction line 1, and each colorimetric item is measured in an 18 second cycle, while the three items for electrodes (Na ⁺ ,
K ⁺ , Cl ^- ) is measured in 54 second cycles, that is, 18 second cycles per item, so it is equivalent to colorimetric measurement.

It goes without saying that the present invention is not limited to the embodiments described above, and can be implemented with modifications within the scope of the gist of the present invention. For example, in an electrode device, it is possible to simultaneously measure not only Na ⁺ , K ⁺ , Cl ^- but also other ion-selective electrode items such as Ca ⁺⁺ . In addition, the flow path from the suction nozzle to the electrode section is set so that it can hold two samples including the electrode section, and the sample sucked from the suction nozzle is first heated to a constant temperature with a heat block. It is also possible to perform measurement at the electrode section during the next suction operation. Furthermore, the flow path from the suction nozzle to the electrode section is set to hold four or more samples, and before the sample flows into the electrode section, it is heated to a constant temperature with a heat block to stabilize the temperature of the sample. You can also do that.

〔Effect of the invention〕

As explained above, the present invention includes an electrolyte analyzer attached to a colorimetric reaction line, and also integrates a constant temperature section (heat block) and an electrode section, thereby reducing the size of the device. It is possible to provide an automatic chemical analyzer that can freely perform colorimetric measurements and electrode measurements with one device without requiring complicated operations, and can also perform precise measurements using the electrode section. Furthermore, since the length of the tube from the electrode suction nozzle to the electrode can be freely set, the location of the electrode device can be freely determined.

[Brief explanation of the drawing]

Fig. 1 is a schematic explanatory diagram showing one embodiment of an automatic chemical analyzer according to the present invention, Fig. 2 is an explanatory diagram showing an extracted electrolyte analyzer which is the main part of the present invention, and Fig. 3 is an electrolyte analysis diagram thereof. A cross-sectional view showing the electrode device of the device; Figures 4a, b, c, d, and e are explanatory diagrams showing the operation up to the point where measurements are taken with the electrodes; Figure 5 shows the electromotive force during calibration. FIG. 6 is an explanatory diagram showing the response; FIG. 6 is a diagram showing the relationship between the recorded power of the ion electrode and the concentration; FIG. 7 is an explanatory diagram showing the electromotive force response during sample measurement. 11... Suction nozzle (suction nozzle),
11a... Vertical movement mechanism, 12... Suction pump (pump), 13... Tube (pipe line), 14...
...Electrode device, 14A... Heat block (constant temperature section), 14B... Electrode section.

Claims (1)

[Claims] 1. In an automatic chemical analyzer capable of colorimetric analysis by photometrically measuring a liquid to be measured stored in reaction tubes arranged in a row, the liquid to be measured is selectively extracted from the row of reaction tubes containing the liquid to be measured. a suction nozzle that can be moved up and down on the reaction tube array to aspirate it; a pump that is connected to this suction nozzle via a pipeline; and a constant temperature controller that is installed in this pipeline and heats the solution to be measured to a predetermined temperature. and an electrode unit that measures the electrolyte of the solution to be measured heated by the thermostatic part, and can be switched to measure both or either of the colorimetric items and the electrolyte items. An automatic chemical analyzer featuring: