JP5372646B2 - Automatic analyzer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an automatic analyzer having a high throughput that performs a small amount of dispensation precisely, improves the cleaning performance, and is able to obtain reliable analysis results. <P>SOLUTION: In the automatic analyzer having a liquid dispensation mechanism that includes a nozzle for sucking liquid, a pressure-changing mechanism for changing pressure within the nozzle and piping for connecting the nozzle to the pressure changing mechanism, the piping comprises a plurality of pieces of pipings, a connection section among the pipings, and the pressure-changing mechanism includes a switching valve for switching which among the plurality of pieces of piping and the pressure changing mechanism are to be connected. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to an automatic analyzer that performs qualitative and quantitative analysis of biological samples such as blood and urine, and in particular, a dispensing mechanism that includes a nozzle that sucks a liquid such as a sample and a reagent and a cleaning mechanism that cleans the nozzle. The present invention relates to an automatic analyzer equipped with

  An automatic analyzer is a device that analyzes a blood component of a patient. The apparatus discharges serum and reagents in the sample container to the reaction container using a dispensing mechanism. After mixing the sample and reagent discharged into the reaction vessel with a stirring mechanism, the concentration of the target component is calculated by measuring the absorbance that changes with time due to the reaction between the reagent and the serum component using a photometer. And output the analysis result.

  When aspirating a specimen or reagent, a liquid transfer device called a plunger is moved to move the liquid in the pipe, thereby performing suction or discharge from the tip of the dispensing nozzle.

  To repeat the above analysis operation, the inner and outer walls of the dispensing nozzle before the next dispensing operation are performed in order to avoid the adverse effects of the sample or reagent remaining in the nozzle being mixed with the next sample or reagent. Is cleaning.

  When washing the inner wall of the dispensing nozzle, it is common to wash the specimen or reagent remaining in the dispensing nozzle by flowing washing water from a pipe connected to the dispensing nozzle.

  When washing the outer wall of the dispensing nozzle, washing water is discharged from a washing nozzle arranged around the dispensing nozzle to wash away the specimen or reagent.

  With this structure, it is possible to transfer the liquid when dispensing the specimen and the reagent and the flow path of the liquid when cleaning the inner wall to be the same pipe, and it is possible to easily clean the inside of the nozzle.

  An automatic analyzer equipped with a mechanism for washing the inside of a nozzle by flowing such a detergent is disclosed in Patent Document 1.

  The amount of washing water at this time is determined by the relationship between the feed water pressure, the pipe diameter, and the washing time, and the carry-over of the sample and the reagent is designed in such a range that there is no clinical problem.

  In recent years, in order to reduce analysis costs, there is a tendency to reduce the amount of liquid, and for dispensing of specimens and reagents, lower dispensing amounts and higher precision are required.

  Furthermore, in an apparatus that integrates biochemistry and immunity, the same dispensing nozzle is used for measurement of immunity items, and thus high detergency is required.

  In addition, in a testing center that handles a large amount of specimens and a hospital with a large number of patients, high processing capability is required in order to quickly report analysis results to the clinical side.

JP-A-4-16767

  The following elements are required to achieve low dispensing volume and high precision.

  The first is to prevent the liquid inside the tube from being pulled by the surface tension of the discharged liquid. For this purpose, it is necessary to reduce the sectional area of the nozzle tip.

  The second is to reduce the variation in the pipe volume and transfer the liquid slowly. For this purpose, it is necessary to reduce the pipe diameter, increase the friction loss, and decrease the flow velocity. Since the energy transmission efficiency is reduced, the influence of disturbance can be attenuated.

  However, as the pipe diameter is reduced, the flow rate decreases, and it becomes difficult to obtain a sufficient amount of cleaning water during cleaning.

  In addition, if an attempt is made to realize a high processing capacity in response to recent demands, one analysis cycle tends to be shortened, and the time allocated for cleaning is also shortened.

  The amount of water to be washed tends to decrease due to a decrease in flow rate and a reduction in washing time. In the future, there has been a risk that the integrated device including the measurement of immune items cannot be sufficiently washed in the probe.

  In addition, current automatic analyzers are equipped with a pressure sensor in the dispensing flow path, and a function to increase the reliability of analysis data by detecting the suction and discharge pressure of the specimen and determining whether suction or discharge has been performed normally is attached. There are many things. For the pressure sensor, a diaphragm type is generally used in view of performance and cost, but in order to improve the sensitivity of the sensor, it is necessary to increase the diaphragm diameter to some extent. On the other hand, when the diaphragm diameter is large, a damper action occurs during suction or discharge, which may affect dispensing accuracy. If the dispensing amount is large, the influence can be ignored, but if the dispensing amount is small, there is a concern that the accuracy may be lowered or the speeding up may be hindered.

  An object of the present invention is to provide an automatic analyzer capable of performing a small amount of dispensing with high accuracy. It is another object of the present invention to provide an automatic analyzer having a high processing capability capable of improving the cleaning performance and obtaining a highly reliable analysis result.

  The configuration of the present invention for achieving the above object is as follows.

  In the automatic analyzer having a liquid dispensing mechanism comprising a nozzle for sucking a liquid, a pressure change mechanism for changing the pressure in the nozzle, and a pipe connecting the nozzle and the pressure change mechanism, the pipe Is an automatic analysis comprising a plurality of pipes, and a switching valve for switching which one of the plurality of pipes is connected to the pressure change mechanism at a connection portion between the pipe and the pressure change mechanism apparatus.

  More preferably, the following configuration is provided.

  By providing two or more flow paths and a solenoid valve for controlling the flow path, the present invention improves the dispensing accuracy and the cleaning performance at the same time by switching the flow paths during dispensing and cleaning. It is characterized by.

  If the dispensing volume is small, the flow path for transferring liquid is switched to the narrowest pipe of the two or more flow paths, increasing friction loss and decreasing the flow speed, and abrupt changes in flow speed. By attenuating, stable dispensing with little variation can be performed.

  On the other hand, when the dispensing amount is large, the flow path for transferring the liquid is switched to a thick pipe in the two or more flow paths. As a result, the frictional resistance is reduced, and the necessary dispensing can be performed in a short time. Although the variation is slightly increased, there is no influence on accuracy because the amount of dispensing is large.

  Further, in the nozzle cleaning process, the cleaning water can be simultaneously supplied to the plurality of flow paths to reduce the friction loss of the pipe, increase the amount of cleaning water, and improve the cleaning performance.

  In particular, if you want to increase the cleaning power, install a three-way solenoid valve in the flow path with the largest pipe diameter, and supply the water pressure from the feed pump without any loss by bypassing the liquid transfer device. Increase the cleaning ability.

  Moreover, by connecting the detergent flow path with a T-shaped pipe in the middle of the flow path, the detergent can be sucked up and flowed to the pipe due to the ejector effect in which the fluid having a high flow velocity sucks the surrounding fluid.

  In addition, a pipe provided with a pressure sensor that detects the pressure in the nozzle among a plurality of pipes is connected to the nozzle and the syringe only when the liquid is sucked into the nozzle, and the liquid is discharged. Can be provided with a switching valve for switching to use a pipe not provided with a pressure sensor so as not to be affected by the damper effect of the diaphragm of the pressure sensor.

  According to the present invention, dispensing accuracy can be improved. Further, the cleaning ability can be improved without increasing the cleaning time of the dispensing nozzle.

The cleaning channel of the present invention is shown in FIG. FIG. 2 shows a cleaning channel using the bypass channel. FIG. 3 shows a cleaning flow path using the charge tank. Configuration example 1 having a pressure sensor. Configuration example 2 having a pressure sensor. Configuration example 3 having a pressure sensor. Configuration example 4 having a pressure sensor. Configuration example 5 having a pressure sensor. Configuration example 6 having a pressure sensor.

  The operation of the automatic analyzer to which the present invention is applied will be described.

  FIG. 1 shows a schematic diagram of a dispensing channel provided with two dispensing channels. A dispensing nozzle 3 for sucking the sample 2 from the sample container 1 is connected to a pipe 4 having a diameter of 0.5 mm. This pipe 4 is branched by a branch pipe 5 into a pipe 6 having a diameter of 0.5 mm and a pipe 7 having a diameter of 2.0 mm, and is connected to a three-way solenoid valve 8. Of the three ports of the three-way solenoid valve 8, the remainder is connected to the syringe 9. The syringe 9 is connected to the water supply pump 11 via the electromagnetic valve 10.

  When the sample is aspirated, the port on the pipe 7 side of the three-way solenoid valve 8 is closed, the plunger 12 is moved, and the sample 2 is aspirated and discharged from the dispensing nozzle 3.

  When washing the dispensing nozzle 3, move the dispensing nozzle 3 to the washing tank 13, open the port on the pipe 7 side of the three-way solenoid valve 8, open the solenoid valve 10, and apply pressure to the pipe 4. The inside of the pipe is washed together with the sample remaining in the dispensing nozzle 3. Wash water passes through the pipe 4 and the pipe 7 and is discharged from the dispensing nozzle 3.

  When dispensing a highly viscous sample, the flow path at the time of dispensing can be connected to the pipe 6 to reduce pressure loss, and a highly viscous sample can be stably sucked and discharged.

  FIG. 2 shows a schematic diagram of a cleaning channel using a bypass channel. A dispensing nozzle 3 for sucking the sample 2 from the sample container 1 is connected to a pipe 4 having a diameter of 0.5 mm. This pipe 4 is branched by a branch pipe 5 into a pipe 6 having a diameter of 0.5 mm and a pipe 7 having a diameter of 2.0 mm, and is connected to a three-way solenoid valve 8. Of the three ports of the three-way solenoid valve 8, the remainder is connected to the syringe 9. The syringe 9 is connected to the water supply pump 11 via the electromagnetic valve 10.

  When the sample 2 is aspirated, the port on the pipe 7 side of the three-way solenoid valve 8 is closed, the plunger 12 is moved, and the sample 2 is aspirated and discharged from the dispensing nozzle 3.

  When washing the dispensing nozzle 3, the dispensing nozzle 3 is moved to the washing tank 13, the three-way solenoid valve 14 is opened, and the water pressure from the water supply pump 11 can be directly supplied to the pipe 7 through the bypass channel 15. Connect as follows. The inside of the pipe is washed together with the sample remaining in the dispensing nozzle 3. The washing water passes through the pipe 6 and the pipe 7 and is discharged from the dispensing nozzle 3.

  Moreover, as a result of the increase in the flow velocity in the pipe due to the decrease in the pressure loss, the detergent can be sucked from the detergent flow path provided in the middle of the pipes 5 to 7 by the ejector effect, and flowed to the dispensing flow path. Thereafter, the three-way solenoid valve 14 is switched again, water is sent to the syringe 9, and the detergent in the pipe is removed.

  FIG. 3 shows a schematic diagram of the charge tank flow path. A dispensing nozzle 3 for sucking the sample 2 from the sample container 1 is connected to a pipe 4 having a diameter of 0.5 mm. This pipe 4 is branched by a branch pipe 5 into a pipe 6 having a diameter of 0.5 mm and a pipe 7 having a diameter of 2.0 mm, and is connected to a three-way solenoid valve 8. Of the three ports of the three-way solenoid valve 8, the remainder is connected to the syringe 9. The syringe 9 is connected to the water supply pump 11 via the electromagnetic valve 10. A three-way solenoid valve 16 is disposed in the middle of the pipe 7 and connected to the charge tank 17.

  Prior to sample aspiration, the three-way solenoid valves 8 and 16 are switched to the pipe 7 and the charge tank 17 side, the solenoid valve 10 is opened, and the pressure is stored in the charge tank 17. Next, the three-way solenoid valve 8 is switched to the pipe 6 side, and the solenoid valve 10 is closed.

  Next, the plunger 12 is moved, and the specimen 2 is aspirated and discharged from the dispensing nozzle 3.

  When washing the dispensing nozzle 3, the dispensing nozzle 3 is moved to the washing tank 13, the three-way solenoid valves 8 and 16 are opened, the solenoid valve 10 is opened, and the sample 2 remaining in the dispensing nozzle 3 is piped. Clean inside. At this time, the pressure stored in the charge tank 17 is released, and the supply of pressurized water from the vicinity of the dispensing nozzle 3 allows the washing water to flow into the dispensing nozzle 3 without pressure loss. Therefore, it can be cleaned in a short time.

  The current automatic analyzer is equipped with a pressure sensor in the dispensing flow path, with a function to increase the reliability of analysis data by detecting the suction and discharge pressure of the specimen and determining whether suction or discharge has been performed normally. There are many. For the pressure sensor, a diaphragm type is generally used in view of performance and cost, but in order to improve the sensitivity of the sensor, it is necessary to increase the diaphragm diameter to some extent. On the other hand, when the diaphragm diameter is large, a damper action occurs during suction or discharge, which may affect dispensing accuracy. If the dispensing amount is large, the influence can be ignored, but if the dispensing amount is small, there is a concern that the accuracy may be lowered or the speeding up may be hindered.

FIG. 4 is a schematic view of a dispensing channel devised to solve the problem.
Dispensing nozzle 3 is connected to pipe 4, pipe 4 is branched into pipe 6 and pipe 21 by branch pipe 5, and pipe 21 is connected to three-way solenoid valve 8 via solenoid valve 22 and pressure sensor 23. ing. The pipe 6 is connected to a three-way solenoid valve 8. The common port of the three-way solenoid valve 8 is connected to the syringe 9. The syringe 9 is connected to the water supply pump 11 via the electromagnetic valve 10.

  When aspirating the specimen, the port on the pipe 6 side of the three-way solenoid valve 8 is opened (the pipe 7 side is closed), the solenoid valve 22 is opened, the plunger 12 is moved, and the specimen is aspirated from the dispensing nozzle 3. To do. The pressure during the suction is detected by the pressure sensor 23 to detect clogging due to foreign matters such as fibrin or insufficient sample.

  As the plunger 12 is stopped, the solenoid valve 22 is closed, the flow path of the dispensing nozzle 3 and the pressure sensor 23 is shut off, the dispensing nozzle 3 is raised from the sample, and the dispensing nozzle 3 is moved to the reaction container and discharged. .

  That is, the pressure sensor 23 and the flow path of the dispensing nozzle 3 are connected during suction, pressure monitoring is performed, and the damper action can be eliminated by closing the flow path after suction, which is necessary to stabilize dispensing accuracy. In addition, the waiting time for establishing the damper action can be shortened.

  At the time of discharge, the flow path between the pressure sensor 23 and the dispensing nozzle 3 is blocked, so that it is not subjected to a damper action, and it is possible to increase the speed and ensure the accuracy of minute dispensing.

  It should be noted that the above-described suction operation is applied only when the amount is small, and it is also effective to change the control depending on the dispensing amount and the liquid property of the specimen, such as performing suction / discharge while the electromagnetic valve 22 is open according to the dispensing amount. . This also has the effect of reducing the frequency of opening and closing the electromagnetic valve 22.

  When washing the dispensing nozzle 3, the dispensing nozzle 3 is moved to the washing tank, the port on the pipe 7 side of the three-way solenoid valve 8 is opened (the pipe 6 side is closed), the solenoid valve 22 is opened, and the solenoid valve 10 is opened. Is opened, pressure is applied to the pipe 4, and the inside of the pipe is washed together with the specimen remaining in the dispensing nozzle 3. The washing water passes through the pipe 7 and is discharged from the dispensing nozzle 3. By making the pressure loss of the pipe 7 small, the cleaning efficiency of the nozzle can be increased. In order to reduce the pressure loss, the thickness may be shortened.

  Further, since there is a pressure sensor in this flow path, it is easy to remove bubbles in the vicinity of the pressure sensor.

  To remove bubbles in the pipe 6, the port on the pipe 6 side of the three-way solenoid valve 8 is opened (the pipe 7 side is closed), the solenoid valve 22 is closed, the solenoid valve 10 is opened, and washing water flows through the pipe 6. This operation may be performed in combination in the cleaning process of the dispensing cycle, or may be performed during maintenance.

  Furthermore, when dispensing a highly viscous sample, the port on the pipe 7 side of the three-way solenoid valve 8 is opened (the pipe 6 side is closed), the solenoid valve 22 is opened to reduce pressure loss, and a highly viscous sample is stabilized. Can be sucked and discharged.

  FIG. 5 shows an example of a configuration that can obtain the same effect as that of the fourth embodiment. The specimen is aspirated by closing the solenoid valve 10 and the solenoid valve 24, opening the solenoid valve 22, and sucking the specimen from the dispensing nozzle 3 by the movement of the plunger 12. At this time, the pressure during the suction is monitored by the pressure sensor 23 to detect a suction abnormality.

  As the plunger 12 is stopped, the solenoid valve 22 is closed, the flow path of the dispensing nozzle 3 and the pressure sensor 23 is shut off, the dispensing nozzle 3 is raised from the sample, and the dispensing nozzle 3 is moved to the reaction container and discharged. .

  The dispensing nozzle 3 is washed by opening the solenoid valve 10, the solenoid valve 24, and the solenoid valve 22 and applying pressure to the pipe 4 from the two flow paths.

  With this series of dispensing sequences, the accuracy of minute dispensing can be ensured as described in Example 4, the dispensing nozzle cleaning efficiency is high, and the dispensing cycle can be speeded up.

  FIG. 6 shows an example of a configuration that can obtain the same effect as that of the fourth embodiment. Although the flow path configuration is partially different from that in FIG. 5, the suction, discharge, and cleaning operations are the same as those in the fifth embodiment.

  FIG. 7 shows an example of a configuration that can obtain the same effect as that of the fourth embodiment.

  The specimen is aspirated by closing the solenoid valve 10 and the solenoid valve 25, opening the solenoid valve 22, and sucking the specimen from the dispensing nozzle 3 by the movement of the plunger 12. At this time, the pressure during the suction is monitored by the pressure sensor 23 to detect a suction abnormality.

  As the plunger 12 is stopped, the solenoid valve 22 is closed, the flow path of the dispensing nozzle 3 and the pressure sensor 23 is shut off, the dispensing nozzle 3 is raised from the sample, and the dispensing nozzle 3 is moved to the reaction container and discharged. .

  The dispensing nozzle 3 is washed by opening the solenoid valve 10, the solenoid valve 25, and the solenoid valve 22 and applying pressure to the pipe 4 from the two flow paths.

  FIG. 8 is a configuration example in which the same effect as in the fourth embodiment can be obtained.

  The pressure loss of the flow path from the pipe 28 to the pipe 21 is configured to be smaller than that of the pipe 6 so that the bubbles of the pressure sensor 23 can be easily removed.

  The specimen is aspirated by closing the solenoid valve 10 and the solenoid valve 24, opening the solenoid valve 22, and sucking the specimen from the dispensing nozzle 3 by the movement of the plunger 12. At this time, the pressure during the suction is monitored by the pressure sensor 23 to detect a suction abnormality.

  As the plunger 12 is stopped, the solenoid valve 22 is closed, the flow path of the dispensing nozzle 3 and the pressure sensor 23 is shut off, the dispensing nozzle 3 is raised from the sample, and the dispensing nozzle 3 is moved to the reaction container and discharged. .

  When washing the dispensing nozzle 3, the dispensing nozzle 3 is moved to the washing tank, the solenoid valve 10, the solenoid valve 24, and the solenoid valve 22 are opened, pressure is applied to the pipe 4, and it remains in the dispensing nozzle 3. Clean the inside of the pipe together with the sample.

  To remove bubbles in the pipe 6, the electromagnetic valve 24 is closed and the electromagnetic valve 10 is opened. At this time, the electromagnetic valve 22 may be either open or closed.

  FIG. 9 shows an example of a small number of flow path component parts and suitable for microdispensing.

  The specimen is aspirated by closing the solenoid valve 10 and the solenoid valve 24, opening the solenoid valve 22, and sucking the specimen from the dispensing nozzle 3 by the movement of the plunger 12. At this time, the pressure during the suction is monitored by the pressure sensor 23 to detect a suction abnormality.

  As the plunger 12 is stopped, the solenoid valve 22 is closed, the flow path of the dispensing nozzle 3 and the pressure sensor 23 is shut off, the dispensing nozzle 3 is raised from the sample, and the dispensing nozzle 3 is moved to the reaction container and discharged. .

  That is, the pressure sensor and the flow path of the dispensing nozzle 3 are connected during suction, pressure monitoring is performed, and the damper action can be eliminated by closing the flow path after suction, which is necessary for stabilizing dispensing accuracy. The waiting time for establishing the damper action can be shortened.

  At the time of discharge, since the flow path between the pressure sensor and the dispensing nozzle 3 is blocked, the damper action is not received, and the speed can be increased and the accuracy of minute dispensing can be ensured.

  In order to clean the dispensing nozzle 3, the electromagnetic valve 22 is closed, the electromagnetic valve 10 is opened, and cleaning water is allowed to flow through the pipe 4. Subsequently, the bubbles of the pressure sensor 23 are removed. The electromagnetic valve 10, the electromagnetic valve 22, and the electromagnetic valve 24 are opened, and air bubbles are also discharged by draining the cleaning water from the pipe 26. The flow path resistance from the pipe 21 to the pipe 26 is set smaller than the flow path resistance from the pipe 4 to the dispensing nozzle 3. This bubble removal step may be performed every cycle at a timing before or after the cleaning operation. It may be performed after starting up the apparatus, before starting the analysis, or by a maintenance operation.

  The operation may be switched depending on the amount dispensed or the liquidity of the sample. In a dispensing amount in which an error due to the damper action does not cause a problem, the frequency of opening and closing the electromagnetic valve 22 can be reduced by performing suction and discharge while the electromagnetic valve 22 is opened.

  By these series of dispensing sequences, the accuracy of minute dispensing can be ensured, the dispensing cycle can be speeded up, and the bubbles of the pressure sensor can be easily removed.

  The purpose of the pressure sensor used in the automatic analyzer is to measure a negative pressure of several kPa generated at the time of suction. However, in order to wash the dispensing nozzle 3 efficiently, in some cases, a high pressure of several hundred kPa is repeatedly received. Therefore, high pressure resistance is required. This hinders cost reduction and high sensitivity of the pressure sensor.

  The pressure sensor 23 in FIG. 4 is assumed to be low in pressure and inexpensive. The suction / discharge process is the same as in the fourth embodiment.

  In the washing process of the dispensing nozzle 3, the port on the pipe 6 side of the three-way solenoid valve 8 is opened (the pipe 7 side is closed), the solenoid valve 22 is closed, and the solenoid valve 10 is opened. Create a state that does not add. As a result, the pressure sensor does not require high pressure resistance and can be made inexpensive. In addition, it is possible to use a pressure sensor with higher sensitivity, and it is possible to contribute to improving the reliability of measurement data such as highly accurate determination of abnormal suction and determination of erroneous suction of bubbles generated on the specimen.

  Such a configuration in which the washing water pressure of the dispensing nozzle is not added to the pressure sensor can also be implemented in FIGS. 5, 6, 8, and 9.

DESCRIPTION OF SYMBOLS 1 Specimen container 2 Specimen 3 Dispensing nozzle 4, 6, 7, 21, 26, 28 Pipe 5, 27 Branch pipe 8, 16 Three-way solenoid valve 9 Syringe 10, 14, 22, 24, 25 Solenoid valve 11 Water supply pump 12 Plunger 13 Washing tank 15 Bypass flow path 17 Charge tank 23 Pressure sensor

Claims (4)

A nozzle for sucking liquid;
A pressure change mechanism for changing the pressure in the nozzle;
A pipe connecting the nozzle and the pressure change mechanism;
In an automatic analyzer equipped with a liquid dispensing mechanism equipped with
The pipe is connected to a plurality of a first pipe having the same diameter as the pipe and a second pipe having a larger diameter than the pipe via a branch pipe, and the first pipe and the second pipe are connected via a three-way solenoid valve. Connected to the pressure change mechanism;
An automatic analyzer that closes the port on the second piping side of the three-way solenoid valve when sucking liquid, and opens the port on the second piping side when cleaning the nozzle . The automatic analyzer according to claim 1,
The automatic analyzer further comprises a pressure detection mechanism for detecting the pressure in the nozzle in the second pipe . The automatic analyzer according to claim 2,
The automatic analyzer further comprises electromagnetic valves at both ends of the pressure detection mechanism of the second pipe . The automatic analyzer according to claim 1 ,
The automatic analyzer further comprises a charge tank disposed in the second pipe via a three-way solenoid valve for supplying pressurized water to the second pipe .

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