JPH05154194A - Continuous measuring instrument for biochemical material - Google Patents

Abstract

PURPOSE:To enable the continuous measurement of the concn. change of a biochemical material. CONSTITUTION:A buffer soln. and a standard soln. of specified concn. of the biochemical material to be measured are accumulated respectively in bottles 8, 9. A sample contg. the biochemical material to be measured flows through a tube from a direction (g) at all times into the bottle 10. A control section 6 injects respectively the specified volumes of the liquids accumulated in the respective bottles into a reaction section 1 by controlling selector valves 4, 5 and a liquid feeder 2. The output signal level of a sensor 12 rises when the standard liquid or sample liquid is injected into the reaction section 1. The control section 6 calculates the concn. in accordance with the value of the output signal when the rising speed is maximized. Namely, the specified volume of the sample liquid is automatically injected into the reaction section 1 and the concn. is determined by the changing speed of the sensor output signal with the device. Then, the continuous measurement is possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for measuring biochemical substances, and more particularly to an apparatus for continuously measuring the concentration change of one sample.

[0002]

2. Description of the Related Art When measuring the concentration of a biochemical substance with a conventional biochemical measuring device, a measurer measures the sample liquid containing the biochemical substance to be measured with a pipette and injects the measured sample liquid into a reaction tank. To do. A sensor is installed in the reaction tank, and the biochemical substance contained in the sample is detected by the sensor. Then, the concentration of the biochemical substance is calculated based on the output signal of the sensor.

[0003]

However, in such a conventional biochemical measuring device, since it is necessary for the measurer to weigh the sample, the change in the concentration of the biochemical substance is continuously changed at sufficiently short time intervals. It could not be measured. Moreover, the reaction time of the sensor was long, and continuous measurement was impossible in that respect as well. As a result, the conventional biochemical measuring device could not know the fluctuation of the urea concentration in the dialysate during artificial dialysis and the fluctuation of the glucose concentration in the blood of the patient during surgery.

An object of the present invention is to solve the above problems and to provide a biochemical substance continuous measuring apparatus capable of continuously measuring a change in biochemical substance concentration at sufficiently short time intervals.

[0005]

DISCLOSURE OF THE INVENTION The present invention relates to a device for measuring the concentration of a biochemical substance, a biosensor for detecting a biochemical substance in a liquid, a sensor reaction section in which this sensor is installed, and this sensor. A first injection device for injecting a fixed amount of buffer solution into the reaction part, a second injection device for injecting a fixed amount of a standard solution containing a biochemical substance into the sensor reaction part at a fixed amount, and the sensor reaction A third injection device for injecting a fixed amount of the sample solution into the section, and a signal processing section for obtaining the concentration of the sample solution based on the speed at which the output signal of the biosensor changes.

[0006]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 shows an example of an apparatus for continuously measuring biochemical substances according to the present invention. The sensor reaction unit 1 has a biosensor 12 installed therein, and has a structure in which the sensor 12 is immersed in the liquid injected into the reaction unit 1. The liquid feeding device 2 is
The liquid is sucked from the h direction via the syringe pump 3,
Pull in the direction. Then, the drawn liquid is weighed, a fixed amount of the liquid is discharged in the j direction, and is injected into the reaction part 1 through the tube 11. The syringe pump 3 is always h → i
The structure is such that the liquid flows only in the direction of → j.

A buffer solution and a standard solution having a constant concentration of the biochemical substance to be measured are accumulated in the bottles 8 and 9, respectively. The bottle 10 is for accumulating a sample solution containing a biochemical substance to be measured, and the sample solution constantly flows in from the g direction through the tube. Bottle 7 is reaction part 1
It is for accumulating liquid discharged from.

The switching valve 4 includes a bottle 8 and a syringe pump 3.
It is possible to set either a flow path between a and b that connects to and a flow path between a and c that connects the switching valve 5 and the syringe pump 3. The switching valve 5 can set either a flow path between d and e that connects the bottle 9 and the switching valve 4 or a flow path between d and f that connects the switching valve 4 and the bottle 10.

The control unit 6 controls the switching valves 4 and 5 to set a flow path, and controls the liquid delivery device 2 so that a certain amount of liquid is injected into the reaction unit 1. Further, it receives a signal from the sensor 12 and processes it to calculate the concentration of the biochemical substance. The calculated concentration is displayed on the display unit 13.

Next, the operation will be described with reference to the flowchart of FIG. The control unit 6 sets the flow path of the valve 4 to the flow path between a and b (step S1), controls the liquid sending device 2 and sends the constant amount of the buffer solution of the bottle 8 to the sensor reaction section 1. Sensor 1
2 is immersed in the buffer solution (step S2). At this time, the control unit 6 takes in the signal output from the sensor 12 (step S3) and stores the value as a value in a state in which the biochemical substance to be measured is not included.

Next, the controller 6 sets the flow path of the valve 5 to the flow path between ed and the flow path of the valve 4 to the flow path between a and c (step S4). After that, the liquid sending device 2 is caused to suck the standard liquid from the bottle 9, and a certain amount thereof is discharged to the reaction part 1 (step S5). As a result, the standard solution is mixed with the buffer solution, and the output signal level of the sensor 12 rises. Control unit 6
Captures the output signal of the sensor 12 (step S
6) The differential value of the output signal is calculated to check whether the differential value is maximum (step S7), and the value of the sensor output signal when the differential value is maximum is stored. This means that the output value of the sensor 12 when the liquid having a constant concentration of the biochemical substance to be measured is injected into the reaction section 1 is known.

Next, the control unit 6 sets the flow path of the valve 4 to the flow path between a and b (step S8), sends the buffer solution to the reaction section 1 and cleans the sensor 12 (step S9). ), Prepare for the next measurement. After that, the flow paths of the valves 5 and 4 are respectively d-
It is set to the flow path between f and a-c (step S1).
0). Then, the control unit 6 causes the liquid feeding device 2 to feed a fixed amount of the sample liquid from the bottle 10 to the reaction unit 1 (step S
11). As a result, the buffer solution in the reaction section 1 and the sample solution are mixed, and the output signal level of the sensor 12 rises. The control unit 6 fetches this sensor output signal (step S1
2) As in the case of the measurement of the standard solution, the differential value of the sensor output signal is calculated, and it is checked whether or not the differential value is the maximum (step S13), and the output signal when the differential value is the maximum. Get the value of. Then, the value is compared with the value at the time of measuring the standard solution to obtain the concentration of the sample liquid, and the obtained concentration is displayed on the display unit 13.

Thereafter, the control unit 6 sets the flow path of the valve 4 to the flow path between a and b (step S15), and the buffer solution is added to the reaction unit 1.
And the sensor 12 is washed (step S16).

Thereafter, the control unit 6 repeats the operation of feeding the sample liquid from the bottle 10 to the reaction unit 1 and measuring the concentration at predetermined time intervals, and displays the concentration obtained on each occasion on the display unit 13 ( Steps S10 to S16). By looking at the display, the measurer can know the change in the concentration of the biochemical substance to be measured.

[0015]

As described above, in the continuous biochemical substance measuring apparatus of the present invention, a fixed amount of the sample liquid containing the biochemical substance to be measured is automatically injected into the reaction section by the third injection device. To be done. Further, since the concentration of the sample liquid is obtained by the signal processing unit based on the changing speed of the output signal of the biosensor, even if the reaction time of the sensor is long, the concentration can be measured in a short time. Therefore, the concentration can be measured at sufficiently short time intervals, and the change in concentration can be continuously measured. As a result, it becomes possible to know the fluctuation of the urea concentration in the dialysate during artificial dialysis and the fluctuation of the glucose concentration in the blood of the patient under operation.

[Brief description of drawings]

FIG. 1 is a block diagram showing an example of an apparatus for continuously measuring biochemical substances according to the present invention.

FIG. 2 is a flow chart for explaining the operation of the biochemical substance continuous measurement apparatus of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sensor reaction part 2 Liquid feeding device 3 Syringe pump 4,5 Switching valve 6 Control part 7-10 Bottle 11 Tube 12 Biosensor 13 Display part

Claims (3)

[Claims] 1. A device for measuring the concentration of a biochemical substance, a biosensor for detecting a biochemical substance in a liquid, a sensor reaction part in which the sensor is installed, and a fixed amount of buffer solution in the sensor reaction part. A second injection device for injecting a fixed amount of a standard solution containing a biochemical substance into the sensor reaction section at a fixed amount, and a fixed amount of sample solution to the sensor reaction section. A continuous measuring device for biochemical substances, comprising: a third injecting device for injecting; and a signal processing unit for obtaining the concentration of the sample solution based on the speed at which the output signal of the biosensor changes. 2. The signal processing unit obtains the concentration of the sample liquid from the value of the sensor output signal when the rate of change of the sensor output signal is maximized. Continuous measuring device for biochemical substances. 3. The first injection device comprises a first injection port into which the buffer solution is injected, a second injection port, and the liquid injected from the first and second injection ports. A first valve having a discharge port for controlling the valve, and a first control unit for controlling the valve, the second injection device having a first injection port for injecting the standard solution, A second valve having two inlets and an outlet for discharging the liquid injected from the first and second inlets; and a second controller for controlling the valve, The continuous measuring device for biochemical substances according to claim 1, wherein the third injection device includes the second valve, and the sample solution is injected into the second injection port.