JPH0454179B2 - - Google Patents

Description

Detailed Description of the Invention (a) Field of Industrial Application The present invention relates to a device for collecting a liquid sample using a suction nozzle for collecting a liquid sample from within a capillary liquid sample container, and particularly relates to a liquid chromatography analysis method,
The present invention relates to a liquid sample collection device for collecting a liquid sample in a flow injection analysis method or other trace liquid analysis methods from a capillary liquid sample container using a liquid sample collection suction nozzle.

Furthermore, the present invention can be applied to body fluids such as blood, plasma, serum, and lymph, excreta such as urine, secretions such as gastric juice, pancreatic juice, bile, saliva, and sweat, and puncture fluids such as ascites, pleural effusion, and joint cavity fluid. The present invention relates to a device for sucking and collecting a liquid sample using a liquid sample dispensing nozzle from a capillary liquid sample container in automatic chemical analysis of a liquid sample.

(b) Conventional technology Among body fluids and biological samples, blood, for example, circulates throughout the body, providing substances such as oxygen, nutrients, and hormones to tissues, and carrying away waste products from tissues. Its composition comprehensively reflects the metabolism of the body's cells and tissues, and changes accordingly if there is a lesion somewhere in the body. Therefore,
Component analysis values of blood and the like are used for diagnosing various diseases, determining the effectiveness of treatments, and providing treatment guidelines.

Moreover, for such medical information, the diagnostic accuracy is higher when multiple analysis items are combined than from a single analysis item, so the number of analysis items required for one sample is increasing, and accordingly, high-quality analysis is required. Precision is increasingly required.

However, most of the analyzes used for diagnosis and treatment guidelines target patients, and the amount of blood collected is limited by the patient's medical condition.
In the case of infants, the amount of blood collected from infants is extremely limited because the total amount of blood is small.

Such a small amount of liquid sample is stored in a so-called capillary liquid sample container. The capacity of the capillary liquid sample container is selected as appropriate depending on the amount of sample collected, and the dimensions vary, but for example, an extremely small capillary liquid sample container with an outer diameter of approximately 1.5 mm, an inner diameter of approximately 0.85 mm, and a length of approximately 75 mm is used. The liquid sample contained therein is collected by suction using a sample collection suction nozzle with an outer diameter of approximately 0.72 mm and an inner diameter of approximately 0.5 mm, for example, as a sample for a high-performance liquid chromatography analyzer. The sample is sent to the introduction section or the sample introduction section of a flow injection analyzer via a conduit, or is discharged into a reaction tube at the sample dispensing position of an automatic analyzer.

(C) Problems to be Solved by the Invention As described above, when a liquid sample is collected by suction from a capillary liquid sample container using a sample collection suction nozzle, in order to prevent air from being taken in,
A suction nozzle is inserted deep into the liquid sample in the capillary container to collect the sample. In this way, the volume of the liquid sample in the capillary container increases by the volume of the suction nozzle immersed in the liquid sample, and the liquid sample in the capillary container overflows from the upper end of the capillary container, contaminating the capillary holder. I will do it. Therefore, in order to avoid analysis errors due to this contamination, it is necessary to clean the capillary holder every time a sample is collected, which requires a special cleaning process and drying process, which is problematic. In addition, if the drying is not sufficient, the overflow portion of the liquid sample will be diluted due to immersion of the suction nozzle into the liquid sample when the next sample is collected, resulting in problems such as analysis errors.

In addition, if the suction nozzle is inserted eccentrically into the capillary liquid sample container, the liquid level will drop more rapidly due to suction on the side where the suction nozzle wall is closer to the capillary container wall than on the other side. , suction of air is a problem. Therefore, when inserting the suction nozzle into the capillary container, it is necessary to center the suction nozzle with respect to the capillary container so that the suction nozzle is not eccentric, and precision is required once again, and the problem still remains. It will remain. SUMMARY OF THE INVENTION The present invention aims to solve the above-mentioned problems in the conventional liquid sample collection device that sucks and collects a liquid sample from a capillary liquid sample container using a sample collection suction nozzle.

(d) Means for Solving the Problems The present invention solves the problem of overflowing the liquid sample from the capillary liquid sample container when the liquid sample is sucked and collected from the capillary liquid sample container using a sample collection suction nozzle. In addition, the present invention provides a liquid sample collection device that does not require precision such as centering when inserting a sample collection suction nozzle into a capillary liquid sample container.

That is, in the present invention, a liquid sample collection suction nozzle is inserted into a capillary liquid sample container, a liquid sample contained in the capillary liquid sample container is sucked into the suction nozzle, and the liquid sample is removed from the capillary liquid sample container. In a liquid sample collection device for collecting liquid samples, a capillary liquid sample container 1 has an upper end fastened to a holder 4 attached to a fixed base 6, and a liquid sample collection suction nozzle whose upper end is connected to a pipette 16. 17 is a nozzle holder 8
A first guide member 11 is attached to one end of the nozzle holder 8, and a first guide member 11 is fixed to the other end of the nozzle holder 8.
The first rack 10 is connected to a first rack 10 disposed vertically in movable engagement with the first rack 10.
The pinion 12 that engages with the pipette 16 is fixed and attached to the rotating shaft of a first power source 13 that has a built-in position detection sensor.
The end of the plunger 17 is connected to a second rack 18 which is provided in movable engagement with a second guide member 19 which is fixedly installed. The matching pinion 20 is fixed and attached to the rotating shaft of the second power source 21 which has a built-in position detection sensor, and the position detection sensor of the rotating shaft of the first power source 13 is connected to the rotating shaft of the second power source 21, which is fixed and has a built-in position detection sensor. detecting from the operating amount of the rotating shaft of the first power source that the liquid level has risen to a predetermined position below the upper end of the capillary container after the suction nozzle 7 is immersed;
The rotation shaft of the second power source 21 is actuated to the suction side of the piston 16, and the position detection sensor of the rotation shaft of the second power source 21 operates the amount of movement of the plunger 17 on the suction side. Liquid sample collection for collecting a liquid sample from a capillary liquid sample container, characterized in that the operation of the rotation shafts of the first and second power sources is stopped by detecting the amount of operation of the rotation shaft of the power source 21. It's in the device.

In the present invention, when a suction nozzle for collecting a liquid sample is inserted into a capillary liquid sample container, the opening of the suction nozzle is immersed in the liquid sample in the capillary container, as in the conventional apparatus. In this method, aspiration of the liquid sample is initiated before the volume within the liquid sample exceeds the top of the capillary liquid sample container. Therefore, the volume of the liquid sample begins to decrease before it exceeds the upper end of the capillary liquid sample container, so as the volume of the liquid sample decreases, the liquid sample is A fixed amount is drawn into the suction nozzle and a liquid sample is taken.

In the present invention, the lowering of the liquid sampling suction nozzle is performed in such a way as to avoid inhalation of air from the surroundings. This is performed by synchronizing a power source such as a stepping motor that lowers the suction nozzle and a power source such as a stepping motor that operates the plunger of a pipette to perform suction of the suction nozzle.

This synchronization is performed so that when the suction nozzle for liquid sample collection has descended to a predetermined position, the plunger of the pipette of the suction nozzle starts suction operation. The position of the suction nozzle is detected by various position detection methods with high detection accuracy. Such position detection methods include mechanical position detection elements such as cams, links, and gear devices, electrical position detection devices such as micro switches, proximity switches, electric micrometers, and electric linear scale pulse motors. Fluid position detecting elements such as an air micrometer or an air micrometer, and optical position detecting elements such as a photoelectric switch or a photoelectric linear scale can be used.

(e) Effect The present invention involves immersing a suction nozzle opening for liquid sample collection into a liquid sample in a capillary liquid sample container, and then sucking the liquid sample while moving the suction nozzle opening downward. Therefore, the liquid sample can be collected by suction without inhaling air and without the volume of the liquid sample exceeding the upper edge of the capillary sample container even though the suction nozzle is immersed. Can be done.

In addition, in the present invention, as long as the suction nozzle for liquid sample collection can descend smoothly inside the capillary liquid sample container, even if the center alignment is not precise,
During the descending stage of the suction nozzle, the imbalance in the liquid level around the suction nozzle can be resolved, so that the liquid sample can be collected by suction while avoiding air suction due to the imbalance in the liquid level.

(F) Examples Hereinafter, an example of an embodiment of the present invention will be described with reference to the accompanying drawings, but the present invention is not limited in any way by the following description and examples.

The figure is a structural diagram schematically showing an embodiment of the liquid sample collection device of the present invention.

In the figure, the lower end of a capillary sample container 1 is sealed with a stopper 2, and the upper end 3 is tightly attached to a holder 4 and fastened with a cap nut 5. Holder 4
is attached to a fixed base 6.

The sample suction nozzle 7 is attached to a nozzle holder 8, and the other end 9 of this nozzle holder is connected to a rack 10 provided vertically, so that it can reciprocate together with the rack 10. Rack 10 is provided with suitable fixing means (not shown).
It is slidably provided on the guide member 11 which is fixed by. A pinion 12 that engages with this rack 10 is attached to a rotating shaft 14 of a first stepping motor 13 fixed at a predetermined position, and the rack 10 is guided by the rotation of the first stepping motor 13. It reciprocates along the member 11.

The sample suction nozzle 7 is connected via a tube member 15 to a pipette 16 which is fixed by suitable fixing means (not shown). The end of the plunger 17 of the pipettor 16 is connected to a rack 18 and reciprocates with the rack 18. The rack 18 is slidably secured to the guide member 1 by suitable securing means (not shown).
The guide member 19 is attached to the guide member 9 and reciprocated along the guide member 19 by rotation of the pinion 20 that engages with the pinion 9 . The pinion 20 is fixed to a rotating shaft 22 of a second stepping motor 21 fixed at a predetermined position, and rotates with the rotation of the rotating shaft. The first stepping motor 13 and the second stepping motor 21 are connected to a synchronizer (not shown) via a signal line 23, and when the sample suction nozzle 7 descends, the sample suction nozzle 7 is inserted into the capillary sample container 1, and its tip 24
However, when the sample is immersed, for example, 2 to 3 mm into the sample liquid 25, the second stepping motor 21 is activated and sample suction is started.

Since this example is constructed as described above, the first stepping motor 13 is operated to rotate the pinion 12 and move the rack 10 downward. As the rack 10 moves, the sample suction nozzle 7 is inserted into the capillary sample container 1 through the guide hole 26 of the holder 4. A position detection sensor (not shown) built into the first stepping motor 13 detects the point where the tip 24 of the sample suction nozzle 7 is immersed in the sample liquid 25 to a certain depth.
The detection signal is sent to the second stepping motor 21 via the signal line 23, and the second stepping motor 21 is operated. Operation of the second stepping motor causes the pinion 20 to rotate and move the rack 18 towards the 19' side. Along with this movement of the rack 18, the plunger 17 of the pipettor 16 moves to the suction side and starts suctioning from the sample suction nozzle 7. As the suction operation of the pipette 16 progresses, the first stepping motor 13 continues to rotate, so that the sample suction nozzle descends within the capillary sample container 1 while sucking the sample liquid 25. When the movement of the plunger 17 on the suction side reaches a certain position, a position detection sensor (not shown) built in the second stepping motor 21 detects this, and the second stepping motor 21
At the same time, this stop signal is sent to the first stepping motor 13 to reverse the rotation of the first stepping motor 13 and move the rack 10 upward. The sample suction nozzle that has sucked a certain amount of sample liquid 25 moves upward together with the rack 10, and when it rises to a predetermined position, it is detected by the position detection sensor built into the first stepping motor 13, and the 1. The operation of the stepping motor 13 is stopped.

This signal to stop the operation of the first stepping motor 13 is sent to a stepping motor (none of which is shown) of a moving device that moves the sample suction nozzle 7 in the horizontal direction.
to the sample discharge position.

When the sample suction nozzle 7 has finished moving to the sample discharge position, in response to this position detection signal, the first stepping motor 13 rotates forward and lowers the sample suction nozzle 7 to a certain position. In response to the detection signal of the descent of the sample suction nozzle 7, the second stepping motor 21 rotates in the opposite direction to the previous suction time, and rotates the pinion 20 in the opposite direction to the suction time. This reversal of the pinion 20 moves the rack 18 to the 19'' side, moves the plunger 17 to the discharge side, and discharges the sample into a sample container for analysis or a sample inlet located at the sample discharge position.Sample. After the sample suction nozzle 7 has finished discharging, the sample suction nozzle 7 moves to the cleaning position, and the second stepping motor is operated alternately in both forward and reverse directions to wash and dry the sample suction nozzle 7.

The sample suction nozzle 7 that has been washed and dried moves to the sample suction position 27, and the operations of the sample suction and collection process, the sample discharge process, and the sample suction nozzle cleaning and drying process using the sample suction nozzle 7 are repeated.

According to this example, sample liquid can be easily collected from the capillary sample container without inhaling air.

(g) Effects of the Invention The present invention immerses a suction nozzle opening for liquid sample collection into a liquid sample in a capillary liquid sample container, and then aspirates the liquid sample while moving the suction nozzle opening downward. Therefore, a liquid sample can be accurately collected from the capillary liquid sample container using the liquid sample collection suction nozzle without inhaling air. Therefore, compared to the conventional liquid sample collection device from a capillary liquid sample container, the present invention reduces sample collection errors due to air inhalation, etc., and can perform highly reliable liquid sample collection. This in turn leads to improved analytical accuracy.

Moreover, since the present invention performs such highly reliable liquid sample collection, it is possible to use precious trace amounts of samples for analysis without waste, compared to conventional devices.
This is extremely useful for diagnosis, etc.

[Brief explanation of the drawing]

The figure is a structural diagram schematically showing an embodiment of the liquid sample collection device of the present invention. Regarding the symbols in the figure, 1 is the capillary sample container, 2 is the stopper, 3 is the upper end, 4 is the holder, 5 is the cap nut, 6 is the fixing base, 7 is the sample suction nozzle, 8 is the nozzle holder, and 9 is the nozzle holder. At the other end, 10 is a rack, 11 is a guide member, 12 is a pinion, 13 is a first stepping motor, 14 is a rotating shaft, 15 is a tube member, 16 is a pipette, 17 is a plunger, 1
8 is a rack, 19 is a guide member, 19' and 19'' are moving directions of the rack, 20 is a pinion, 21 is a second stepping motor, 22 is a rotating shaft, 23 is a signal line, and 24 is the tip of a sample suction nozzle. , 25 is a sample liquid, 26 is a guide hole, and 27 is a sample suction position.

Claims (1)

[Claims] 1 A liquid sample in which a suction nozzle for liquid sample collection is inserted into a capillary liquid sample container, the liquid sample contained in the capillary liquid sample container is sucked into the suction nozzle, and the liquid sample is collected from the capillary liquid sample container. In the sampling device, a capillary liquid sample container is fastened to a holder whose upper end is attached to a fixed base, and a liquid sample collection suction nozzle whose upper end is connected to a pipette is attached to one end of the nozzle holder. the other end of the nozzle holder is movably engaged with a first fixed guide member and connected to a vertically disposed first rack; The pinion that engages with the pipette is fixed and attached to the rotating shaft of the first power source that has a built-in position detection sensor, and the end of the plunger of the pipette is connected to the second guide that is fixed. a pinion connected to a second rack movably engaged with the member, the pinion engaging the second rack;
The position detection sensor of the rotation shaft of the first power source is fixed and attached to the rotation shaft of the second power source that has a built-in position detection sensor. It detects from the amount of operation of the rotating shaft of the first power source that the rise of the surface has reached a predetermined position below from the upper end of the capillary container, and then operates the rotating shaft of the second power source to the suction side of the Pepitus. The position detection sensor of the rotating shaft of the second power source detects the amount of movement of the plunger on the suction side from the operating amount of the rotating shaft of the second power source, and A liquid sample collection device for collecting a liquid sample from a capillary liquid sample container, characterized in that the operation of a rotating shaft is stopped.