JPS61114158A - Analysis instrument - Google Patents

Abstract

PURPOSE:To obtain an instrument which is small-sized and with which a sample suction nozzle is surely cleaned to permit analysis with high accuracy by providing the suction nozzle of which the top end can be moved in an arc shape, an electrode for measuring the sucked sample, an arithmetic unit for processing the signal from the electrode, a system for cleaning the suction nozzle, etc. to said instrument. CONSTITUTION:The sample is sucked by a suction pump 4 in the position shown by the dotted line by the sample suction nozzle 1 having a movable mechanism 1a in such a manner that the top end thereof can be moved in the arc shape as shown by an arrow. The sucked sample is passed through a measuring electrode 5. The sample is measured in a measuring part 6 and the result thereof is arithmetically processed in the arithmetic unit 7 and thereafter the result is displayed on a display part 8. A notch 2a through which the top end of the nozzle 1 ending the sample suction can pass through is provided to a cylindrical vessel 2 having the inside diameter larger than the outside diameter of the nozzle 1. The nozzle 1 is positioned as shown by the full line after suction and measurement of the sample, and the washing liquid is fed from a washing liquid vessel 9 to the vessel 2 by a liquid feed pump 13 and is made to overflow from the top end of the vessel 2 so as to flow through a liquid receiving part 3 into a waste liquid vessel 10. The inside diameter of the vessel 2 is suitably selected according to the outside diameter and length of the nozzle so that the cleaning liquid arrives at the top end of the notch 2a. The cleaning of the outside surface of the nozzle is made possible as well. The simple cleaning with the small size is thus made possible.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an analysis device using an electrochemical electrode for measuring the concentration of components in a sample liquid.

[Technical background of the invention and its problems]

In recent years, with the development of various technologies for biochemical testing of blood and urine, various analytical devices have been developed. By making full use of these various analytical devices, it has become possible to appropriately understand pathological conditions.

However, in order to reduce the influence of each measurement liquid and increase measurement accuracy, conventional analyzers use pumps equipped with large torque motors that can draw liquids at high speed, standard calibration liquids, cleaning liquids, etc. In order to inhale liquids, a flow path system with a large number of switching valves is installed, and in order to inhale various liquids, a liquid suction nozzle is required to perform complicated operations. The analyzer has become complicated and large in size, and its complicated mechanism has disadvantages such as failures and difficult maintenance.

Therefore, there is currently a demand for a compact, highly accurate analyzer that does not take up much space when installing various analyzers in limited facilities, and that can be easily maintained and inspected. However, in such miniaturized devices, it is not easy to clean the sample liquid suction nozzle, and if cleaning is incomplete, not only will the reliability of measured values be significantly reduced, but also contamination between samples may occur. There were many problems such as problems such as the following.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to provide a compact and highly accurate analyzer having a mechanism that allows easy and reliable cleaning of a sample nozzle.

[Summary of the invention]

The present invention provides a suction nozzle whose tip moves in an arc shape by a movable mechanism, a suction pump that suctions a sample liquid from the suction nozzle, a measurement electrode that measures the sample liquid sucked by the suction pump, and a signal from the measurement electrode. a measurement system consisting of a measurement calculation process that processes;

A cylindrical container having a through hole into which the tip of the suction nozzle is inserted and having an inner diameter larger than the outer diameter of the suction nozzle to house the tip of the suction nozzle; A cleaning system consisting of a liquid receiver for receiving the flowing liquid;
An analysis apparatus comprising: a cleaning liquid container; and a liquid feeding system comprising a cleaning liquid container and a liquid feeding pump that supplies the cleaning liquid from the cleaning liquid container to the cylindrical container.

A schematic diagram showing the configuration of the analyzer according to the present invention is shown in FIG.
A) and a perspective view of the cleaning system are shown in FIG. 1(b).

The tip of the sample liquid suction nozzle (1) is normally housed and protected in a cylindrical container (2) as shown in the figure. When measuring a sample, the suction nozzle is moved by a movable mechanism (1a
), so the through hole (
From 2a), pull out in the direction shown by the arrow and move in an arc to the position shown by the dotted line.

The sample liquid is then pumped through the suction nozzle (1) by the suction pump (4).
) and passes through the pole (5) for measurement, and then passes through the measuring section (6
), and the measurement result is displayed on the display section (8)I, which is subjected to arithmetic processing by the arithmetic section (7).

These measurement section (6), calculation section (7), and display section (8) constitute a measurement calculation processing section. Further, the suction nozzle that has finished suctioning returns to its normal position and its tip is stored in the cylindrical container (2) again.

Since the sample liquid suction nozzle, which has been measured by the measuring system, has sample liquid adhering to both its inner and outer surfaces, cleaning to wash away the sample liquid is carried out by the cleaning system and the liquid feeding system as follows. That is, the cleaning liquid sent from the cleaning liquid container (9) by the liquid feeding pump (13) through the cleaning liquid feeding pipe (1)) is injected from the lower end of the cylindrical container and overflows from the through hole on the side surface and the upper end. Here, the through hole need only have a size that allows the tip of the suction nozzle to be inserted therein, and the inner diameter of the cylindrical container, the outer diameter and length of the sample suction nozzle, the flow rate of the cleaning liquid flowing in, etc. By adjusting the amount, it is possible to cause a sufficient amount of cleaning liquid to overflow not only from the through hole but also from the upper end of the cylindrical container. In this way, the outer surface of the suction nozzle tip is especially cleaned. The waste liquid used for cleaning flows through the liquid receiving part (3) and is further sent to the waste liquid container through the cleaning waste liquid discharge pipe α3.

On the other hand, during this cleaning, the sample liquid suction pump (4) suctions the cleaning liquid injected from the cleaning liquid supply pump to mainly clean the inner surface of the suction nozzle and the measurement system through which the sample liquid has passed. At this time, it is preferable that the amount of suction by the sample liquid suction pump is equal to or less than the amount of cleaning liquid delivered by one cleaning liquid feeding pump. This is because if the suction amount of the sample liquid suction pump is larger than the cleaning liquid output amount of the cleaning liquid supply pump, air mixed with the cleaning liquid will be sucked in through the sample liquid suction nozzle and further flow through the measurement system. This is because air impairs the stability of the measuring electrode, and it takes a considerable amount of time to return to a steady state, resulting in a lack of reliability of the measured value. In addition, considering the case where air may be mixed in due to disturbances such as pump pulsation when the suction amount and delivery amount are the same, the outer surface of the suction nozzle should be sufficiently cleaned so that the cleaning liquid overflows from the upper end of the cylindrical container. For this reason, it is preferable that the amount of cleaning liquid delivered by the cleaning liquid feeding pump is larger than the suction amount.

Furthermore, by using the cylindrical container having the through-hole as described above, the surface tension of the liquid allows the cylindrical container to be filled with liquid up to the upper end while the suction nozzle is housed in the normal state after measurement and cleaning is completed. This allows the measurement system through which the sample liquid flows to be completely filled with liquid, which is preferable for preservation and stability of the measurement electrode. Furthermore, it is preferable to use this liquid as a standard calibration liquid that also serves as the cleaning liquid, since there is no need for a switching mechanism between the cleaning liquid and the standard calibration liquid, and the apparatus is further simplified. On the other hand, if the suction nozzle is stored with the liquid filled to the top of the cylindrical container, the liquid level of the standard calibration liquid, etc. that filled the cylindrical container must be lowered to the tip of the suction nozzle during measurement. By moving the suction nozzle from the suction nozzle, it is possible to prevent contamination of the sample liquid caused by the standard solution adhering to the outer surface of the tip of the suction nozzle, and to improve the reliability of the measured values, which is preferable.

5. Electrodes that can be used in the present invention are conductivity electrodes;
pH, Na+, Ni+, NH4+, Ca", C1-
Ion selective electrodes such as Ox, Co1, NH
gas-sensitive electrodes such as s; enzyme electrodes and microbial electrodes sensitive to glucose, uric acid, urea, pyruvic acid, lactic acid, etc.;

〔Effect of the invention〕

Since the analyzer of the present invention has the simple structure described above, it is compact, the inner and outer surfaces of the tip of the suction nozzle can be easily cleaned, and highly reliable measurements can be performed.

[Embodiments of the invention]

An analysis device having the structure shown in FIG. 1(a), which is detailed in the summary of the present invention, was manufactured. The measurement electrodes used were a combination of ion-selective electrodes that measured Na'', Ni+, and Ct- ions, respectively. In addition, small peristaltic pumps were used as the suction pump and liquid delivery pump, and the rotation speed was adjusted. The amount of suction and amount of liquid delivered were controlled.Furthermore,
A cleaning solution that also served as a standard calibration solution was used as the cleaning solution. The operation of the analyzer will be explained below in order.

(1) Before measurement, the tip of the suction nozzle is inserted into the cylindrical container through the through hole. The liquid level of the cleaning liquid, which also serves as the standard calibration liquid, in the cylindrical container is lowered to the tip of the suction nozzle due to the short-time operation of the suction pump.

(ll) The tip of the measuring suction nozzle is moved by the movable mechanism out of the through hole of the cylindrical container to the sample liquid suction position. Next, inhale the sample solution. In this example, blood was used as the sample liquid.

The single inhalation amount is approximately 200 μt.

After suction has been completed, the tip of the suction nozzle is placed back into the through hole of the cylindrical container, and the sample that has been suctioned has sufficiently reached the installed ion-selective electrode, where it is measured. The value is stored in a temporary calculation unit.

Cl1l) The inner surface and outer surface of the distal end of the suction nozzle, which has been cleaned and housed, as well as the measurement electrode and the flow path for the sample liquid, are contaminated due to adhesion of blood in the sample liquid.

Therefore, first, a cleaning liquid that also serves as a standard calibration liquid is injected from the lower end of the cylindrical container so that it sufficiently overflows from the upper end of the cylindrical container, and in particular, the outer surface of the tip of the suction nozzle inserted through the through hole is cleaned.

The used cleaning liquid flows into the liquid receiving section and is further disposed of into a waste liquid container. After this washing continues for 0.5 to 2 seconds, the suction pump is activated to suck out the washing liquid while injecting the washing liquid in the same manner. In this way, any sample remaining on the inner surface of the suction nozzle or the measuring system is washed away. At this time, the pump was controlled so that the suction amount of the suction pump was slightly smaller than the injection amount of the infusion pump for the reasons described above. Therefore, at this time, cleaning was performed with the cleaning liquid flowing out little by little from the through holes on the sides and from the top end.

On the other hand, the cleaning waste liquid accumulated in the scattering/receiving part (3) is disposed of into the waste liquid container On through the discharge pipe 04. This device uses natural drainage by gravity, but forced drainage using a pump may also be used. For example, when a peristaltic pump is used as the liquid sending pump a, it is also possible to connect two tubes to one pump so that it can serve both as liquid feeding/draining.

(1v) Calibration The ion-selective electrode used determines the ion concentration contained in the sample by comparing and calculating the measured value of the sample liquid and the measured value of the standard calibration liquid. In this apparatus, since the cleaning liquid that also serves as the standard calibration liquid reaches the ion electrode during the (lull) cleaning, measurements for calibration are performed at that point.

(■) The measured value of the sample stored at the time of measurement of display (1)) and (
The ion concentration of the sample is determined by comparison and calculation with the measured value of the standard calibration solution measured at the time of calibration in IV) and is displayed.

After this, when measurements were to be continued, the liquid level of the cleaning liquid, which had filled to the top of the cylindrical container, was lowered to the tip of the suction nozzle to maintain the state before the measurement in (1).

In this way, the series of operations required for one measurement was completed, and the time required for this was approximately 40 seconds. or,
When a predetermined period of time or more elapses until the next measurement (for example, overnight), the cylindrical container is filled to the top with cleaning liquid to protect the suction nozzle and the like. In that case, when measuring again, the liquid level was lowered to state (1) by reversing the liquid pump, and then the measurement was performed.

On the other hand, in order to protect this, in addition to the method described above, forced cleaning is performed at regular intervals to constantly fill the measuring system, etc. with cleaning liquid to prevent drying due to evaporation from the tip of the suction nozzle. You can do it like this.

Alternatively, in addition to the series of operations described above, it is of course also possible to perform cleaning once before measuring the sample, perform measurements for calibration if necessary, and then measure the sample.

In this way, 50 consecutive measurements were performed using blood as a sample using the analyzer according to the present invention, and each measurement was thoroughly cleaned and calibrated to eliminate the influence of previous measurements. This also made it possible to extremely reduce contamination between samples. The Cv values at this time are Na'', K+, C
L- each was 1% or less.

Furthermore, we conducted 300 consecutive analyzes and measurements, and were able to achieve the same accuracy as above.

The suction nozzle and the cylindrical container having a through hole on the side surface in the analyzer of the present invention are such that the tip of the suction nozzle can be accommodated in the cylindrical container through the through hole provided on the side surface of the cylindrical container, and The drawn-out suction nozzle may have any shape as long as it can suck the sample liquid. For example, Figure 2a.

As shown in b, c, d, and e, the tip of the suction nozzle may be straight or bent. Further, the cylindrical container does not need to be upright; it may be inclined and have a through hole provided therein.

[Brief explanation of the drawing]

FIG. 1(a) is a schematic diagram showing an analysis device according to the present invention,
FIG. 1(b) is a perspective view showing the cleaning section of the analyzer according to the present invention, FIG. 2(a), (b), (C),
(d) and (e) are schematic cross-sectional views showing other embodiments of the cleaning section of the analyzer according to the present invention. 1... Suction nozzle, 1a... Movable mechanism, 2...
- Cylindrical container, Qa...through hole, 3...liquid receiving part, 4...suction pump. 5... Measuring electrode, 6... Measuring section, 7... Calculating section, 8... Display section, 9... Cleaning liquid container,
10... Waste liquid container, 1)... Cleaning liquid feeding pipe, 12
...Cleaning waste liquid discharge pipe, 13...Liquid pump.

Claims (2)

[Claims] (1) A suction nozzle whose tip moves in an arc shape by a movable mechanism, a suction pump that suctions the sample liquid from the suction nozzle, a measurement electrode that measures the sample liquid sucked by the suction pump, and a signal from the measurement electrode. a measurement system comprising a measurement calculation processing unit for processing; and a measurement system having a through hole on a side surface into which the tip of the suction nozzle is inserted, and having an inner diameter larger than an outer diameter of the suction nozzle; a cleaning system consisting of a cylindrical container for storing the liquid and a liquid receiving part for receiving the liquid flowing out from the cylindrical container; and a cleaning liquid container and a liquid sending pump for supplying the cleaning liquid from the cleaning liquid container to the cylindrical container. An analysis device comprising: a liquid feeding system; (2) The analyzer according to claim 1, wherein the cleaning liquid also serves as a standard calibration liquid.