JPS5847261A - Method and device for analyzing liquid sample - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the analysis of samples swamped in flow channels. The method and device according to the invention are particularly suitable for use in the automated analysis of clinically relevant specimens, but also in the automated analysis of agricultural, pharmaceutical and industrial specimens.

Various analytical devices are known. Among them is what is known as a Discrete Analyzer, which consists of two separate containers.
A book is placed, but the specimen typically remains in the container during the analysis process. This device has the advantage that each specimen can be separated separately, thus minimizing the possibility of mixing up specimens.

Another type of analyzer is one in which the sample under test and the reagent are injected into one chamber, the two are allowed to mix, and the reaction mixture is passed from that chamber to the measuring chamber. The time during which the mixture is placed in the measurement chamber is a short period of time during which measurements, such as photometric measurements, are being carried out.

In other analytical devices, the specimens are continuously moved through a carrier stream that follows a narrow channel designed to isolate each specimen from adjacent specimens.

In that example, air parcels are used to separate specimens in a moving carrier stream from each other. In another example,
This includes what is known as flow injection analysis, in which the reagents with which each sample reacts are used as transport vehicles. In this case, a precisely measured sample is injected into the reagent stream at a predetermined point. The injection means can be, for example, a syringe through the septum or a rotary valve. In the latter rotary valve, the holes provided in the valve all constitute a measuring device, and when a somewhat larger sample is injected through the hole,
The hole rotates to direct the injectate into the reagent stream.

Even though the injection sample becomes elongated as it passes through the narrow tube forming the flow path, it remains in one piece without dispersing.

The swatch mixes with the reagent by being diffused radially from the boundary layer. For this flow injection analysis to be successful, it is therefore necessary to avoid the occurrence of turbulence. This device has the advantage of allowing specimens to be tested more quickly without adversely affecting the results of an analysis compared to devices in which the specimens are separated by air. But at the same time
It also has the disadvantage of increasing the amount of reagents used, which are often expensive requisites.

According to one aspect of the invention, in an analyzer for a liquid sample to be conveyed to the analyzer through a flow path.

9- Inject the sample and reagent into separate branches of the channel that meet at the rear, and use a single pump to pump the sample and reagent mixture into the channel; There is provided an analytical device characterized in that by introducing a carrier liquid into a flow path by a pump, a substance in the flow path is transported in a continuous liquid phase.

According to another aspect of the present invention, in a method for analyzing a liquid sample transported by a carrier liquid through a flow path, a predetermined sample and a selected reagent are each extracted from separate containers in fixed amounts and separated into separate analysis streams. introducing the extraction sample and the extraction reagent in a common channel; moving the sample-reagent mixture through the channel as a separating liquid arm inserted into the flow of the carrier liquid; and sending the sample to the measuring chamber of the analyzer.

In contrast to the prior art, the method of the present invention does not inject the sample and reagent (either separately or together) into a carrier liquid that is already introduced into the flow path.

The sample and reagent are injected into separate channels that merge or combine with each other at the rear. Therefore, the method of the present invention does not require the prior introduction of any liquid into the channel during sample and reagent injection.

The method of the invention can also be used to analyze a series of specimens in succession. Analysis can be performed even when a plurality of specimens are present at different positions within the flow path at the same time, or when one specimen is present within the flow path at any given time.

The method of the invention does not require the use of air bubbles to disrupt the carrier liquid. Therefore, the substance in the channel is a series of liquids, and the liquid isolate (hereinafter referred to as the "active zone") consisting of a mixture of sample and reagent is sandwiched between front and back by the carrier liquid. It exists. If distilled water is used as the carrier liquid, it is convenient because there is no need to use a carrier liquid that is difficult to mix with the active region.

The method of the present invention is carried out under conditions where laminar flow exists within the flow path, and relatively low pressure is required for the movement of substances within the flow path.

It is preferable that the flow path is constructed of a tube with an inner diameter of 1 mm or less and no obstructions inside. Commercially available polyethylene 17 tubing has been found to be sufficient.

Preferably, the sample, reagent, and drug are extracted from their respective containers by extraction needles or dip tubes connected to small diameter tubing connected to a screw pump. The extraction needle can remain in the reservoir of carrier liquid until the active zone is introduced into the flow path.

The extraction needles are then transferred from the carrier fluid reservoir to the sample and reagent storage containers.

The helical pump is preferably driven by a stepper motor under microprocessor control so that the stepper motor can make precisely controlled angular movements. By doing so, it becomes possible to accurately control the ratio of the active region passing through the flow path and the carrier liquid.

Microprocessor control of the stepper motor not only allows for precise control of the material in the flow path, but also makes the method of the invention extremely versatile and can be tested continuously. The dimensions of the specimens, the spacing between them, and the time selected for analyzing and measuring the specimens can also be varied individually.

It is desirable that the amount of extraction reagent be greater than the amount of extraction sample. For example, a Y-shaped piece of plastic pipe or a T-piece.
When the swatch and reagent meet at the point formed by the strip, the active area thereby formed will ensure good mixing of the swatch and reagent and will reduce the amount of reagent used. It is also economical.

The pump tube connected to the extraction needle used for reagent extraction can be formed to have a larger diameter than the other pump tube. This way, for a given square turn of the screw pump, more reagent will be drawn up than the sample being tested.

Typically, the flow path comprises a coiled small diameter tube of sufficient length to allow the sample and reagent to remain in contact with each other for the desired amount of time. The flow path is also provided with an analysis point, for example a flow chamber in a colorimeter.

According to still another aspect of the present invention, in an analyzer for a liquid sample transported in a flow path by a carrier liquid, a predetermined sample extracted from one individual container and a selected reagent are separated into separate branches by a predetermined amount. means for direct and simultaneous introduction into the flow path; a helical pump for moving the fluid along said flow path; connected or connectable to said helical pump for precise angular movement; An apparatus is provided having: a stepper motor that can be controlled in a controlled manner; a means for introducing an extraction sample and an extraction reagent into a common flow path; and means for analyzing and measuring substances in the flow path.

The analytical measuring means may be, for example, a spectrophotometer.

It is convenient to control the step motor with a microprocessor. This is because the microprocessor can also be used to control an analytical device, such as a spectrophotometer, and to process data generated by the device.

The apparatus further includes a turntable for receiving and holding specimens to be analyzed. The turntable is preferably controlled by a number display activated directly or indirectly by a stepper motor and controlled by a microprocessor.

The method and apparatus according to the invention are particularly useful for clinical analysis. The method and apparatus of the present invention can be used to obtain data from instantaneous reactions between samples and reagents. For example, when measuring the amount of calcium in serum, the sample is mixed with a reagent consisting of a cresol phthalene binding solution. A blue color develops immediately, and the intensity of the blue color is proportional to the calcium concentration in the sample. In this type of instantaneous reaction, the active mass can pass through the flow chamber of the colorimeter without stopping, and the maximum signal emitted by the spectrophotometer indicates the calcium concentration of the sample in question. There is.

The method and apparatus of the present invention can also be used to collect data from samples that react slowly with reagents. For example, when measuring the amount of glucose in serum, a sample of the serum to be tested is mixed with the enzyme glucose dehydrogenase. The mixture is typically incubated at 30C;
As a result of the reaction, the coenzyme nicotinimide-adenine dinucleotide is reduced and absorbs ultraviolet light in the spectrum. In this type of test, the active mass is drawn up into the flow chamber of the colorimeter, at which point the pump is stopped and the signal emitted by the colorimeter is observed for a predetermined period of time, such as 15 seconds. The rate of change in the colorimeter signal during observation is therefore proportional to the concentration of glucose contained in the serum sample.

Next, one embodiment of the device according to the present invention will be described below along with the accompanying drawings.

In the drawing, a pair of extraction needles 1.2 are inserted into a container S containing a sample to be analyzed and a container R containing a reagent reacting with the sample.

An extraction needle control mechanism 3 operated by a step motor 5 via a number display device 4 is provided. This extraction needle control mechanism 3 functions to transfer the extraction needle from the sample and reagent container to a third container C which serves as a reservoir source for an inert carrier liquid 1, such as distilled water. The position of the extraction needle within container C is indicated by dotted lines 1' and 2'.

The sample container S is placed on a rotating table (not shown) 17- on which a series of samples are successively analyzed by one analyzer. The step motor 5 is controlled by a microprocessor 6. The device according to the invention also has a screw pump 7. The operation of this screw pump is carried out by a stepper motor 5 under the control of a microprocessor 6. The substance in the extraction needle 1.2 is transferred to the conduits 8, 9 (formed by small diameter plastic tubing) by the movement of the screw pump.
are sucked up along respectively f3a and 9a respectively.
The flow passes through the pump at 1 and reaches the Y-shaped section 10, where the two flows respectively flow into the tubular section Bh.

They are merged together via 9h. An elongated flow path 11 connected to a measurement chamber 12 of the spectrophotometer is provided downstream of the Y half piece 1o. The output 13 from the spectrophotometer is sent to the microprocessor 6 and one or more analysis parameters obtained from the output 13 are displayed on a display unit 14. After the fluid passes through the measurement chamber 12 of the spectrophotometer,
It is sent to the processing unit 1518-. A flow path extending inside the analyzer includes extraction needles 1 and 2. Conduits 8 and 8α, 9 and 9α.

8h and 9h, Y half piece 10. It consists of an elongated flow path 11° and a passageway to a processing section 15.

This channel can be formed entirely of small diameter polyethylene tubing. It is preferable that the inner diameter of the tube forming the flow path is one inch or less. Portions 8a and 9a of the flow path are known as pump tubes. Since the screw pump 7 operates so that the roller exerts uniform linear driving motion on its two pump tubes, the volume of liquid pumped out by one revolution of the pump roller is proportional to the inner diameter of the pump tube. There is.

Therefore, by using pump tubes 8a and 9α with different inner diameters, the volume ratio of the sample and reagent extracted from the containers S and R, respectively, can be freely changed.

The device according to the invention, which is diagrammatically shown in the accompanying drawings, operates as follows.

At the beginning of the analysis, the two extraction needles are in the position indicated by the dotted lines, ie, immersed in a reservoir source of carrier liquid, such as distilled water. If the screw pump is operated in this state, distilled water will be introduced into the device, which will also perform a purifying function. When the screw pump 7 is deactivated, there is no fluid flow within the flow path of the device. The extraction needle control mechanism 3 is then started by a step motor 5 and a number display device to move the container C.
Lift up the extraction needle from above and insert the extraction needle 2 into the reagent using the extraction needle 1 as a sample. The microprocessor then starts the stepper motor 5 to operate the screw pump 7. The helical pump delivers precise amounts of sample (e.g. serum) and reagents to the extraction needles 1 and 2 by performing predetermined angular movements.
Introduce each into the Since the inner diameter of pump tube 9α is larger than the inner diameter of pump tube 8α, it is ensured that the amount of reagent drawn up by a given angular movement of pump 7 is greater than the amount of sample drawn up by the same movement of the pump. I can do it. Subsequently, the operation of the screw pump is stopped, and the extraction needle control mechanism 3 returns the extraction needles 1 and 2 to the storage source CVC of the carrier liquid. Next, by starting the screw pump 7 again, the sample and reagent that have been sucked into the extraction needles 1 and 2 are introduced into the pump 7, and distilled water is sucked up from the container C into the flow path. The substances in the channel form a continuous liquid phase as they immediately follow the introduced sample/reagent. With continued operation of the pump, each mass of sample and reagent joins at Y-half 10 into a single active mass that migrates along the remaining flow path within the analyzer. It is self-evident to design the length and inner diameter of tubular parts 8b and 9b to ensure that sample and reagent reach single-piece part 10 at the same time.

Further, the turntable that holds the samples is rotated so that one sample 21 to be analyzed next is in a position to receive the extraction needle 1. After a certain period of time has elapsed, the operation of the screw pump I is stopped once again, and the substance flowing in the flow path of the analyzer 1 is also stopped.

Next, the extraction needle control mechanism 3 moves the extraction needles to the containers S and R, so that the sample to be analyzed first can be introduced into the analyzer together with the corresponding reagent.

It will be appreciated that continued operation in accordance with the method described above will result in a series of active masses passing through the flow path of the analyzer. Depending on the selected operating method, it may be possible for a plurality of active masses to exist simultaneously in the flow path while being separated from each other by a columnar carrier liquid 1 of a predetermined length, such as distilled water. Alternatively, the device could be controlled such that a previous sample passes through the channel and reaches the processing section before the next sample is introduced into the channel.

22- Each active mass consists mostly of pure reagent at both ends;
A central portion sandwiched by the ends can consist of a mixture of sample and reagent. As each active mass passes through the elongated channel 11, a reaction occurs between the sample and the reagent. The length of the channel 11 is set to be sufficient to ensure complete mixing of the sample and reagent. When the active mass reaches the measurement chamber 12 of the spectrophotometer, optical measurements are taken and the results are sent as output 13 to the microprocessor 6. This output may be displayed directly on the display unit 4, or a microprocessor may be used to calculate one or more analytical variables obtained by optical measurement.

Which of the above methods is employed will be determined by the respective properties of the specimens/reagents used in a particular analysis.

Optical measurement using a spectrophotometer may be performed with the active mass flowing through the spectrophotometer without interruption, or may be performed with the active mass stationary within the measurement chamber 12. The former method is adopted when the reaction between the sample and the reagent is instantaneous, or when both reactions are complete by the time the active mass reaches the measurement chamber 12, while the latter method is used when the reaction between the sample and the reagent is instantaneous or complete by the time the active mass reaches the measurement chamber 12. This method is adopted when the reaction is slow, that is, when the reaction is still in progress when the active mass reaches the measurement chamber 12.

The operation of the analytical device described above takes place under relatively low pressure and under conditions where laminar flow is present. The substance in the flow path is a continuous liquid, and there is no need to use air bubbles or difficult-to-mix liquids to form divisions in order to maintain the independence of adjacent active masses from each other. It is possible to test a large number of specimens, and even the specimens to be analyzed.
The testing rate can also be varied depending on the properties of the reagent.

Since the step motor 5 is operated using the microprocessor 6, the amount of sample/reagent introduced into the analyzer can be made accurate. The volume ratio of the sample and the reagent is determined by the ratio of the inner diameters of the pump tubes 8α, 9α formed by plastic tubes. It is a relatively simple matter to replace one or both of the pump tubes with another pump tube in order to change the desired volume ratio and thus the proportion of sample and reagent introduced into the apparatus. Creating a program for the microprocessor 6 to act on the step motor 5 to adjust the dimensions of the sample, the length of the columnar carrier liquid existing between the samples, and the rest time of the substance in the measurement chamber 12. is possible.

Some test examples of the present invention will be shown below.

Test Example 1> The apparatus of the present invention was tested using the Jaff stone kinematic method.
It was used for the analysis of serum creatine 25-25 using the etic Jaffa method. In this test, the amount of creatine contained in the sample is calculated using the property that creatine turns red when it reacts with picric acid (2,4,6-)linitrophenol] and caustic soda. A spectrophotometer equipped with a 7V source lamp and a 505m filter was used to measure the progress of discoloration. The inner diameter of the pump tube 8α (for the serum sample to be tested) was 0.03 inch (0.76 Wn), and the inner diameter of the pump tube 9α (for the picric acid-caustic soda reagent) was 0.065 inch (1.6!l1 m). The flow path 11 has an inner diameter of 0.03 inches (0,000 mm) wound around an automatic temperature control type heater that maintains the temperature of the liquid at 25R.
It was constructed of 76 m) of coiled plastic tubing.

The rotational speed of the screw pump 7 during operation was 75 per minute. The microprocessor operates the pump with an inhalation time of 10 seconds to directly suck up the sample and reagent into separate channels 1 and 2, respectively, and then stops the pump and moves the extraction needle to the deionized pump for the carrier liquid. It was programmed to move to container C containing water. With the dimensions of the pump tube as described above and the suction time of 10 seconds, 15 microliters of sample and 65 microliters of reagent were extracted from containers S and R, respectively.

The pump was then activated for 3 seconds to transport the active mass formed at the 10 points to the measurement chamber 12 of the spectrophotometer. Next, the operation of the pump is stopped for 15 seconds, during which time the measurement chamber 12
An optical illusion of color change in . Subsequently, the pump 7 was operated for an additional 6 seconds to discharge the active mass out of the channel. The amount of creatine in the sample was determined by standard color analysis and the result was 14.

Test Example 2 In order to evaluate the accuracy of the apparatus and method described in Test Example 1, the same analysis was repeated using 20 serum samples and the results were recorded. Then use the same sample with the same J
A commercially available centrifugal analyzer (
The results were compared with those of the former. Both results were virtually the same, and the correlation coefficient (71?-=0.98).

<Test Example 3> The accuracy of the method described in Test Example 1 was evaluated using a creatine solution prepared in advance as a sample. The amount of creatine is a) 128 mmol/l.

b) 33Qmmol/l and c) 970mmol/l
Ten analyzes were performed using the sample. The coefficient of variation (cV) was calculated for each of the three quantities: cV is the standard deviation expressed as a percentage of the mean value, also known as the relative standard deviation. The results obtained are as follows: Creatine amount (mmol/l,) c V (
%) 128 6.0330
2.6970
3.5 Although the device of the invention has been described above in connection with the measurement of optical variables using a spectrophotometer, it may be used in conjunction with or in place of a spectrophotometer depending on the nature of the substance being tested. Analytical instruments may also be used. Therefore, depending on the type of analysis, it may be useful to conduct electrochemical measurements on the substances passing through the channel using, for example, an electrolytic recorder.

[Brief explanation of drawings]

The accompanying drawing is a schematic diagram depicting an embodiment of an analytical device according to the invention. 1.1', 2.2'... Extraction needle, 3... Extraction needle control mechanism, 4... Number display device, 5... Step motor, 6... Microprocessor, 7... screw pump,
8, 9... Lead 29-pipe, 8α, 9α... Pump pipe, Bh, gh... Tubular portion, 10... Y half piece, 11... Elongated channel, 12
...Measurement room, 13...Output, 14...Number display device, 15...Processing department procedure amendment (Mutsu) 10/13/1981 1, Indication of incident 1981 Patent application No. 141594 No. 2, Name of the invention: Method for analyzing liquid samples and its device 3, Relationship with the person making the amendment Patent applicant name: Vicars Limited 4, Agent: 104 Telephone Tokyo 543-5873 5, Subject of amendment = 421 −

Claims (1)

[Claims] (1) Predetermined amounts of a predetermined sample and selected reagent are each extracted from separate containers and introduced simultaneously into separate channels; the extracted sample and extraction reagent are introduced into a common channel. The mixture of the sample and reagent is sandwiched between the front and back by the flow of the carrier liquid, and is transferred along the flow path in the form of a liquid mass independent of the carrier liquid and sent to the measurement chamber in the analyzer. : Consists of things. Method for analyzing liquid samples. (2) In a method for analyzing a liquid sample in which the liquid sample is transported through a flow path to the measurement chamber of an analyzer, separate branch channels and reagents are introduced in the flow path that merge at the rear. and using a single pump to move the sample and reagent mixture along the flow path; the pump draws a carrier liquid into the flow path, thereby making the material in the flow path continuous. It is characterized by: being transported in a liquid phase. (3) The samples and reagents are emotional pumps (perista).
The method for analyzing a liquid sample according to claim 1 or 2, wherein the inside of the flow path is characterized by tic pump). (4) The liquid book analysis method according to claim (3), wherein the sample and reagent are extracted with a hollow extraction needle connected to the emotion pump by a small diameter tube. (5) The liquid sample analysis method according to item (3) or (4), wherein the emotional pump is driven by a step motor under the control of a microprocessor. (6) A single separated mass consisting of the sample and reagent is formed by passing through the channel at a predetermined time. A method for analyzing a liquid sample according to any one of the claims. (7) A plurality of masses of the sample and reagent separated from each other by the carrier liquid forming a predetermined columnar shape simultaneously pass through the channel. A method for analyzing a liquid sample according to any one of claims (1) to 5). How to analyze a sample. (9) The sample and reagent meet at a Y-shaped piece or a T-shaped piece that forms a part of the flow path. A method for analyzing a liquid sample according to any one of the claims. (10) The method for analyzing a liquid sample according to any one of the claims, wherein the amount of the reagent introduced into the flow path is greater than the amount of the sample. (11) The -9 tubes and the reagent mass in the flow path are subjected to spectrophotometric analysis. A method for analyzing a liquid prefecture according to any one of the claims. (12) In a liquid sample analyzer that is transported through a flow channel by a carrier liquid, a predetermined sample and a selected reagent are each extracted in fixed amounts from separate containers and introduced directly and simultaneously into separate branch flow channels. means for moving the liquid along the flow path; a stepper motor coupled or connectable to drive the motion pump and controlled to provide precise angular movement; A liquid sample analysis device comprising: means for merging an extraction sample and an extraction reagent into a common flow path; and means for performing an analytical measurement on a substance within said flow path. (13) The device further includes a microprocessor that controls the step motor. Claim No. (12)
The liquid egg weight analyzer described in Section 1. (14) Claim 12, wherein the means for performing analytical measurements on the substance in the flow path is a spectrophotometer.
Alternatively, the liquid sample analysis device described in item (13). (15) The receiver further includes a turntable for taking and holding a sample to be analyzed. Claim No. (12)
, (13) or (14), the liquid sample analysis device according to item (13) or (14). (16) The rotary table is controlled by a number display device that is operated directly or indirectly by the step motor and controlled by the microprocessor. A liquid sample analysis device according to claims (13) and (15). (17) The liquid sample analysis device according to any one of claims (12x16), wherein the flow path is constituted by a small diameter tube having an inner diameter of 1 or less. 5-(18) According to any one of claims (12) to 17), wherein the means for merging the extraction sample and the extraction reagent into a common flow path is a Y-shaped piece or a T-shaped piece. Analyzer for 9 liquids. (19) The means for simultaneously extracting fixed amounts of the sample and reagent is a pair of hollow extraction needles. A liquid sample analysis device according to any one of claims (12) to 18). (20) Claim 13 further comprising an extraction needle control mechanism operated by the step motor via a number display device under the control of the microprocessor.
) and the liquid sample analysis device described in (19). 6-