JPS60205346A - Flow-through type analysis device - Google Patents

Abstract

PURPOSE:To enable exact control of specimen concn. with a simple operation by injecting a specimen into a buffer soln. at the flow rate which is made inversely proportional to the concn. of a component in order to analyze a specified amt. of specimen. CONSTITUTION:A specimen is uniformly diffused with a specified flow rate of a buffer soln. during passage through a coil 8 for diffusing sample and arrives at glucose oxidase 11b immobilized to an electrode 11 after dilution to a specified rate when the specimen is injected into a pipe 5 at a specified rate Q0 per unit time at a discharge flow rate V1 from a sample injector 1 while the buffer soln. is fed into said pipe by operating a pump 6. The glucose oxidase generates the hydrogen peroxide proportional to the concn. of glucose while consuming the dissolved oxygen of the buffer soln. by receiving the effect thereof and the signal proportional to said concn. is emitted from the sensitive surface 11a of the electrode formed integrally therewith. When the flow rate is decreased to V2 by decreasing the frequency of an oscillator 2 in the stage of analyzing the specimen at a high concn., the amt. of the specimen decreases and the concn. of the glucose decreases in proportion as well. The specimen is thus detected with high linearity without inducing saturation.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Application of the Technology The present invention relates to a flow-through type analyzer using immobilized enzymes.

2. Description of the Related Art Immobilized enzyme electrodes, in which enzymes are immobilized on the electrode surface, are often used as detectors in flow-through type analyzers because they are easy to maintain and manage.

However, since the immobilized enzyme electrode detects the target component via a component generated by reaction with a specific component contained in the buffer solution, it exhibits linearity only in a limited concentration range. For this reason, the sample is stopped and diluted before being injected into the analyzer, or the sample is injected into the hemp flow path in a small field and detected while being diluted with a buffer solution, but in the former method, A pretreatment step is required to dilute the sample prior to analysis, which poses an obstacle to automation.
Furthermore, the latter method has the problem that the measurement of the sample is likely to include errors due to the difficulty of measuring small acids, which reduces the reliability of the analysis results.

C. Objectives In view of the above-mentioned problems, an object of the present invention is to provide a flow-through type analyzer that can obtain high analysis accuracy using an immobilized enzyme electrode.

The structure of the present invention, that is, the feature of the present invention is that a fixed amount of the sample is injected into the buffer solution at a flow rate that is inversely proportional to the concentration of the component to be analyzed.

E. Embodiments The details of the present invention will be explained below based on illustrated embodiments.

FIG. 1 shows an embodiment of the present invention, in which reference numeral 1 indicates a sample injection device, and a pulse motor 1a that is rotationally driven by the output from a pulse oscillator 2, and a pulse motor 1a that is driven to rotate by the output from a pulse oscillator 2. It consists of a syringe lb that discharges at a proportional flow rate, and a branch pipe is connected to the discharge port, and one valve 1c and one valve 1 are connected to the discharge port.
d to test sample 111 population 3 and sample liquid tank 4,
By adjusting the frequency of the pulse oscillator 2, the discharge flow rate, that is, the amount of sample injected per unit time can be changed. 5 is a buffer liquid transfer pipe whose one end is connected to the buffer γ liquid tank 7' via the pump 6 and the other end is connected to the sample diffusion coil 8; Injections 1-13 are provided. Reference numeral 9 denotes a flow cell whose one end communicates with the outflow side of the sample diffusion coil 8 and the other end communicates with the waste liquid tank 10. As shown in FIG. It is configured by providing a glucose detection 1rL pole 11 formed by immobilizing llb.

In this embodiment, while the pump 6 is operated to feed the buffer solution into the vibrator 5 at a constant wave rate, a constant skewer of the sample Qo is discharged from the sample injection device 1 at a flow rate v1 and Ql per unit time. When the sample is injected (Fig. 3), the sample is uniformly diffused into the Pant's γ liquid while passing through the sample diffusion coil 8, and is aliquoted at a constant ratio, and then transferred to the glucose oxidase Ilb immobilized on the electric J4i11. Reach 41. Glucose in the sample that has reached glucose oxidase 1lb is acted upon by glucose oxidase, which consumes dissolved oxygen in the buffer solution and generates hydrogen peroxide in proportion to the glucose concentration. The sensitive surface 11a of the electrode outputs a signal proportional to the glucose concentration.

Next, when analyzing a sample containing a high concentration of glucose, try lowering the oscillation frequency of the pulse oscillator 2;] lower the wave velocity of the sample ejected from the injection device 1 to 2; As a result, the amount of sample per unit volume of Yatsufa liquid decreases (Fig. Detected by

Although this example has been explained using the analysis of glucose as an example, the same effect can be applied to the analysis of urea using other fixed oxygen, such as urea, with high linearity. can do. In addition, in this embodiment, the discharge flow rate was adjusted by controlling the rotation speed of the motor, but a continuously variable transmission mechanism may be used, or even a rotary pump may be used to achieve the same effect. Needless to say, it plays.

As described above, according to the present invention, when a sample is injected into the conduit for supplying the buffer solution to the flow cell, a fixed amount of the sample is discharged at a flow rate inversely proportional to the concentration of the analyte component. Since it was made to be discharged into the Yatsufa liquid flow,
Specimen coupling can be accurately controlled at IF by adjusting the pump outlet, and analysis using enzymatic reactions can be performed with high reliability.

[Brief explanation of drawings]

Fig. 1 is a configuration diagram of a device constituting an embodiment of the present invention;
The figure is a cross-sectional view showing an example of the detection electrode, Figure 3 (I) (T
I) is an explanatory diagram showing the operation of the two devices, respectively. ■...Sample injection device 3...Test sample 1 lower entry point
...Buffer 11 9...Flow cell 11...
・Immobilized enzyme electrode applicant Shimadzu Corporation Representative Patent attorney Haruto Nishikawa Katsuhiko Kimura

Claims (1)

[Claims] In a flow-through type analyzer in which a sample is injected into a channel equipped with an immobilized enzyme electrode and transferred while being diluted with a buffer solution, the sample is injected into the channel using a sample 4 injection means that can adjust the discharge wave speed. A flow-through type analyzer characterized by: