JP2000046846A - Method for detecting clog of suction channel or suction amount insufficiency, sample liquid-sucking apparatus, and dispensing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect a clog of a suction channel or a suction amount insufficiency by detecting a pressure in the suction channel after the stop of a suction action for a sample liquid, calculating a change rate from the detected pressure and comparing the change rate with a predetermined threshold. SOLUTION: A pressure sensor 8 is connected to piping 3 for measuring a suction pressure. A pressure signal 9 from the sensor 8 is sent to an amplifier 10 and an amplified pressure signal 11 is sent from the amplifier 10 to a control part 6. The signal is converted to a digital signal by an A/D converter 12 at the control part 6 and sent to a CPU 13. The CPU 13 sends a chip head drive signal 15 and a pump drive signal 7 from the control part 6 to drive a chip head 2A in accordance with a preliminarily set order and drive a dispensing pump 4 to carry out a dispense operation. The CPU 13 incorporates inside an operating part for operating a change rate of the suction pressure on the basis of the signal 11 from the sensor 8, a memory part for storing a threshold of the pressure, an operating part for operating a threshold corresponding to a suction volume, and a comparing part for comparing the change rate of the pressure obtained by the operation with the stored threshold or operated threshold.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for detecting clogging of a suction flow path or a shortage of a suction amount performed when a predetermined amount of a sample liquid is suctioned, and a sample liquid suction apparatus suitable for the detection method. A method for detecting a clogged suction channel or a shortage of suction volume, which can determine the normality of suction by measuring the pressure of the suction channel when dispensing a liquid, etc., and is suitable for using this detection method. The present invention relates to a sample liquid suction device.

[0002]

2. Description of the Related Art In the field of clinical examination, a liquid sample (sample liquid or sample) such as blood serum or plasma collected from a human body is placed in a sample container, and a number of sample containers are set on a sample rack. It is sent to the inspection process. Then, the sample rack is set in a dispensing device equipped with a sample liquid suction device for performing a predetermined test of the sample.

After the sample rack is set in the dispensing device, the sample transfer arm provided in the dispensing device is moved to the nozzle head when the suction mounting portion of the dispensing pump system is a nozzle head, or to the suction head. When the mounting portion is a chip head, a disposable chip is mounted on the chip head.

[0004] The tip of a disposable tip attached to a nozzle head or a tip head is immersed in a sample solution in a sample container, a dispensing pump is operated, and a required amount of sample is aspirated from the sample container to the disposable tip. The required amount of the aspirated sample is dispensed from the disposal chip to each container of the immune reaction cartridge.

However, when the sample contains solid matter such as fibrin, when the sample is sucked into the disposable tip by the dispensing pump, the solid matter is adsorbed to the suction port of the minute disposable tip. As a result, it is difficult to perform a smooth and correct suction operation. If the sample is not properly aspirated into the disposable tip, the required amount of the sample cannot be dispensed into the container of the immune reaction cartridge, and a correct test result cannot be obtained. Therefore, it is necessary to monitor whether or not the work of sucking the sample from the sample container to the disposal tip is performed correctly.

Therefore, as a method of monitoring whether or not a correct suction operation is being performed, a pressure value in a suction flow path at the time of sucking a sample liquid is measured and compared with a pressure threshold value determined according to a suction amount. Thus, there is a method of judging whether the suction flow path is clogged or not, and discriminating between the case where the sample liquid is normally collected in the container and the case where an abnormality occurs in the suction work (Japanese Patent Laid-Open No. 10-48220). Publication No.).

[0007]

However, in this method, when a shortage of the sample suction amount (aspirated amount) occurs as shown in FIG. Since the maximum value of the pressure measured by the gauge pressure is almost equal to the normal suction, it may be determined that the suction is normal, and it is difficult to correctly determine the normality of the suction work.

Accordingly, the present invention provides a detection method and a detection method capable of determining not only a suction abnormality due to clogging but also a suction abnormality due to a shortage of suction amount, and more accurately and reliably determining the normality of a suction operation. It is an object of the present invention to provide a sample liquid suction device using the same.

[0009]

In order to achieve the above-mentioned object, a method for detecting clogging of a suction channel or insufficient suction amount according to the present invention comprises the step of clogging a suction channel performed when a predetermined amount of a sample liquid is suctioned. Or in the detection method of the suction amount shortage;
Detecting the pressure in the suction flow path after stopping the suction operation of the sample liquid; calculating the rate of change from the detected pressure; comparing the calculated rate of change with a predetermined threshold to block or suck the suction flow path; It is characterized in that the amount shortage is detected. The pressure in the suction channel is detected, the rate of change is calculated from the detected pressure, and the calculated rate of change is compared with a predetermined threshold. Shortage can be detected. Detecting the pressure in the suction channel substantially detects the suction pressure. The rate of change is typically the rate of change of pressure. Instead of measuring the pressure in the suction channel, the pressure in the syringe section may be measured when a syringe-type suction pump is used. This is because the pressure in the syringe section is substantially equal to the suction pressure.

Further, the predetermined threshold value may be determined in accordance with a suction amount of the sample liquid. Since the rate of change varies depending on the amount of suction of the sample liquid, a threshold value corresponding to the amount of suction is determined.

Further, the change rate may be a change rate between when the suction operation is stopped and when a predetermined time has elapsed after the suction operation is stopped. Whether or not the suction flow path is clogged or the suction amount is insufficient is noticeable in the magnitude of the value of the rate of change between the time when the suction operation is stopped and the time when the predetermined time elapses from the time when the suction operation is stopped. The rate of change is compared with a predetermined threshold.

The rate of change between when the suction operation is stopped (first time point) and when a predetermined time elapses after the suction operation is stopped (second time point) is the difference between the suction pressures at the two points. May be divided by the time difference between the first and second time points, or the slope of the pressure change may be obtained, or the first time point and the second time point may be further finely divided to obtain the change rate of the divided section, They may be averaged, or an intermediate one of the rates of change may be adopted. This increases reliability.

The suction of the sample liquid is usually performed by the suction operation of the sample liquid suction pump. The end of the suction operation is, for example, the end of the suction operation of the suction pump, that is, in the case of a syringe type suction pump. Means stopping after the piston of the syringe is withdrawn for a predetermined stroke.

Further, the rate of change may be a rate of change between two predetermined points after a predetermined time has elapsed since the suction operation was stopped.

This is because the specific rate of change when the suction flow path is clogged or the suction amount is insufficient becomes noticeable after a lapse of a predetermined time from the stop of the suction operation. Rather than fixing the first point and the second point one by one, several kinds are appropriately selected for one sample solution, and the first point and the second point are combined, and the first point and the second point are combined. The determination may be made based on whether or not the rate of change between the second point and the second point may fall below or exceed a predetermined threshold. The threshold value is not limited to one, and two or more threshold values may be provided.

To achieve the above object, a sample liquid suction device according to the present invention, as shown in FIG. 1, comprises a pressure sensor 8 for detecting a pressure in a suction flow path; and calculating a rate of change from the detected pressure. An operation unit 13; a storage unit 13 for storing the calculated change rate threshold; and a comparison unit 13 for comparing the change rate with the threshold.

Further, the apparatus may further include a calculation unit for calculating the threshold value in accordance with the suction amount of the sample liquid.

To achieve the above object, a dispensing apparatus according to the present invention comprises: a sample liquid suction device according to claim 5 or 6; a holding section for holding a container for accommodating the sample liquid; A moving device that relatively moves the suction channel and the holding unit;

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing a main configuration of a dispensing apparatus 1 including a sample liquid suction apparatus using a detection method for detecting clogging of a suction flow path or insufficient suction amount according to the present invention. When a sample liquid is dispensed, the sample liquid is sucked. Therefore, the dispensing apparatus will be described below mainly on the suction. The dispensing apparatus 1 has a chip 2. The chip 2 is for aspirating a sample (sample liquid) that is a liquid to be dispensed and a specimen liquid. The tip 2 is inserted into a sample container (not shown) containing a sample, and descends until the tip of the tip 2 is below the surface of the sample liquid to suck the sample. The chip 2 is attached to a chip head 2A, and a pipe 3 is connected to the chip head 2A.

The chip head 2A has a communication path (not shown) for communicating the chip 2 with the pipe 3. Chip head 2A
Is further connected to a chip head moving means 14, and the movement of the chip head 2 A (that is, the movement of the chip 2) is controlled according to a chip head moving signal 15 sent from the control unit 6 to the chip head moving means 14. It is performed by The pipe 3 is connected to a dispensing pump 4. Pump driving means 5 is connected to the dispensing pump 4, and the pump driving means 5 drives the dispensing pump 4 according to a pump control signal 7 sent from the control unit 6 to the pump driving means 5.

A pressure sensor 8 for measuring a suction pressure is connected to the pipe 3. The pressure sensor 8 has a built-in pressure transmitter. The pressure signal 9 from the pressure sensor 8 is sent to the amplifier 10, and the expanded pressure signal 11 is sent from the amplifier 10 to the control unit 6. The pressure signal 11 is an analog signal, and is converted into a digital signal by an A / D converter 12 built in the control unit 6, and this digital signal is sent to a CPU 13 built in the control unit 6. The suction pressure is measured by gauge pressure. The pressure sensor 8 may be attached to the chip head 2A to measure the pressure of the chip head 2A. This is because the pressure of the chip head 2A is substantially equal to the suction pressure.

The CPU 13 has a program section, in which a program for controlling the dispensing apparatus 1 is set. The chip head 2A is driven in accordance with a predetermined sequence by the program, and the tip head movement signal 1 is driven so that the dispensing pump 4 is further driven to perform the dispensing operation.
5. The pump drive signal 7 is sent from the control unit 6. CPU
Reference numeral 13 denotes a calculation unit that calculates a change rate of pressure (suction pressure) based on data converted into a digital signal by the pressure signal 11 from the pressure sensor 8, and a storage that stores a pressure threshold value corresponding to the suction capacity. The program includes a unit, a calculating unit that calculates a threshold value corresponding to the suction volume, and a comparing unit that compares the rate of change in pressure calculated by the calculation with the stored threshold value or the calculated threshold value.

When the threshold value is calculated, for example, when the suction volume is a certain value, when the storage unit does not store a volume value completely equal to the value and the threshold value corresponding thereto, the given suction volume is given. By interpolation or extrapolation
In this case, a threshold value corresponding to the value of the suction volume is calculated from a data group of the suction volume and the threshold value corresponding to the suction volume stored in the storage unit.

The tip 2 is transported by the tip head moving means 14 so that the tip 2 is directly above the position where the sample container filled with the sample is set. Next, chip 2
The tip 2 is lowered right below by the tip head moving means 14, the tip 2 is inserted into the sample container, and stopped when the tip of the tip 2 reaches a predetermined distance below the liquid level of the sample. A series of operations of the sample container and the chip 2 and subsequent operations of the dispensing apparatus 1 are performed by the CPU 13 of the control unit.
Is performed according to a program incorporated in the dispensing device 1
Is activated automatically.

After the above-mentioned stop of the chip 2, the dispensing pump 4 is operated by the pump driving means 5 to suck and collect the required whole liquid amount (dispensing amount) or the excess amount.
The tip 2 maintains the stopped state during the suction of the sample.

FIG. 8 shows the structure of the dispensing pump 4 in more detail (FIG. 8 shows the tip 2, the tip head 2A, the pipe 3, the dispensing pump 4, the pump driving means 5, the pressure sensor 8, and the tip head movement. Only the means 14 is shown, and others are omitted). The dispensing pump 4 has a cylindrical syringe 4A having a nozzle 4D at one end, a piston 4B inserted into the syringe 4A from the other end of the syringe 4A, and a piston rod 4C coupled to one end of the piston 4B opposite to the insertion tip.
The nozzle 4D of the syringe 4A is connected to the pipe 3. The end of the piston rod 4C opposite to the end connected to the piston 4B is connected to the pump driving means 5.

Accordingly, by pulling the piston rod 4C through the pump driving means 5, the piston 4B inserted into the syringe 4A is pulled out in the outward direction AA.
The sample is sucked into the chip 2 by the piston 4B being withdrawn in the outward direction AA. Piston rod 4
When C stops moving in the outward direction AA, the piston 4B also stops moving, and the suction operation of the dispensing pump 4 ends. Tip 2 which was at a negative pressure even after the suction operation of dispensing pump 4 was completed
Suction of the sample is performed until the internal pressure (suction pressure) becomes substantially equal to the atmospheric pressure.

Next, after the end of the suction operation, the chip 2 is lifted right above by the chip head moving means 14, and the tip of the chip 2 comes to a predetermined height from the upper end surface of the sample container (not shown in FIG. 8). Stop when Next, the chip 2 is transferred by the chip head moving means 14 until the chip 2 comes directly above a predetermined container (not shown in FIG. 8) of the immune reaction cartridge, and stops.

Next, the chip 2 is moved to the chip head moving means 1.
The procedure in which the sample is dispensed into the container of the immunoreaction cartridge after being transferred to just above a predetermined container of the immunoreaction cartridge according to 4 will be described.

The chip 2 is inserted into the container of the immunoreaction cartridge by the sample chip head moving means 14, and stops at a predetermined depth below the reagent liquid level in the container. Next, the pump driving means 5 operates,
The sample is discharged into the container in an amount sufficient to react with the reagent in the container.

The operation of discharging the dispensing pump 4 is performed as follows. As described above, the piston rod 4C of the dispensing pump 4
The end opposite to the end connected to the piston 4B is connected to the pump driving means 5. Therefore, by pushing the piston rod 4C via the pump driving means 5,
The piston 4B in the syringe 4A is pushed and inserted in the inner direction BB. The sample is discharged to the outside of the chip 2 when the piston 4B is pushed and inserted in the inner direction BB, and the discharged sample is dispensed into the container of the immune reaction cartridge. The piston rod 4C moves by a predetermined stroke toward the inside direction BB of the syringe 4A so that a predetermined amount is dispensed. Similarly, the piston 4B also moves by the above-described predetermined stroke toward the inside direction BB of the syringe 4A. . The syringe 4A stops moving, and the discharge operation of the dispensing pump 4 ends.

After the dispensing is completed, the tip is replaced with a new chip 2 and the dispensing operation of the next sample is performed. The dispensed sample is mixed with the reagent solution in the container,
After incubation for a predetermined time, a predetermined test is performed.

When the sample is sucked from the sample container to the chip 2 and the sample is discharged from the chip 2 to the container of the immune reaction cartridge, the suction pressure and the discharge pressure of the piping fluctuate. If dispensing is successful, see Figure 2,
As shown in FIGS. 3 and 4, immediately before starting the suction of the dispensing pump 4, the pipe 3 detected by the pressure sensor 8 is used.
Is equal to the atmospheric pressure, and the suction pressure is a negative pressure from the start S of the suction operation of the dispensing pump 4 to the end E of the suction operation. At the start of the suction operation of the dispensing pump 4, the suction pressure starts to decrease by dropping from the atmospheric pressure, and when the suction operation of the dispensing pump 4 has progressed to some extent, the pressure drop becomes gentle, and the value eventually becomes minimum. After that, the pressure gradually rises, but the pressure does not completely return to the atmospheric pressure at the end E of the suction operation of the dispensing pump 4.

Even when the suction operation of the dispensing pump 4 is completed, the suction of the liquid to be dispensed into the chip 2 is continued, and the suction pressure continues to recover and rise. This is because the suction line (tip 2, nozzle head 2A, pipe 3, dispensing pump 4) has flow resistance. Therefore, there is a time zone in which the pressure change rate has a certain value other than zero after the end of the suction operation of the dispensing pump 4. Then, when the transfer of the liquid to be dispensed to the chip 2 is completed, the suction pressure is restored to a state close to the atmospheric pressure.

FIG. 2 shows a case where the suction volume is 100 μl, FIG. 3 shows a case where the suction volume is 50 μl, and FIG. 4 shows a case where the suction volume is 20 μl. FIG. 6 is a pressure waveform diagram obtained by measuring the pressure. The horizontal axis represents time, one division is 20 msec, and one side of the square horizontal axis represents 100 mm. The vertical axis represents the pressure signal of the suction pressure, one division is 2 volts (V),
The upward direction is the direction in which the pressure increases, and the downward direction is the direction in which the pressure decreases (the same applies to other pressure waveform diagrams, that is, FIGS. 5 and 6). In the figure, S indicates the position at the start of the suction operation, and E indicates the position at the end of the suction operation of the dispensing pump 4. The suction pressure before the start of suction is equal to the atmospheric pressure, and the suction pressure when the pressure recovery is completed after the pressure has been reduced to a negative pressure by suction is substantially equal to the atmospheric pressure. The reason why the pressure is not completely equal to the atmospheric pressure is due to the force due to the viscosity of the liquid to be dispensed.

On the other hand, when the amount of the liquid to be dispensed is insufficient, FIG.
As shown in the figure, the suction pressure recovers earlier than at the end of the suction operation E of the dispensing pump 4 at the time of normal dispensing. At the end point E of the suction operation of the dispensing pump 4, the suction pressure has recovered to a level close to the atmospheric pressure. For this reason, the pressure change rate of the suction pressure after the end point E of the suction operation of the dispensing pump 4 is substantially equal to zero. The suction volume in the case of FIG. 5 is 50 μl. Such a phenomenon is observed not only when the liquid to be dispensed in the sample container is insufficient but also when, for example, a large amount of air bubbles are sucked together with the liquid to be dispensed for some reason.

If a solid or insoluble matter is present in the liquid to be dispensed and the tip 2 is clogged during suction, the suction pressure increases during the suction operation of the dispensing pump 4 as shown in FIG. Although the pressure drops from the atmospheric pressure, the pressure fluctuation of the suction pressure after the end of the suction operation E differs from the case where the suction is performed normally and the case where the amount of the liquid to be dispensed is insufficient. While in contact with the liquid, a state in which the suction pressure does not recover to near atmospheric pressure continues. For this reason, after the suction operation of the dispensing pump 4 is completed, until a certain time elapses (tip 2
Until the tip of the liquid is separated from the liquid to be dispensed and the contact is stopped), the pressure change rate of the suction pressure is almost zero. The suction volume in the case of FIG. 6 is 20 μl.

Accordingly, suction is performed using a calculation formula based on the pressure value of the suction pressure at the end E of the dispensing pump 4 at the end of the suction operation and the pressure value of the suction pressure after a lapse of a predetermined time from the end of the suction operation of the dispensing pump 4. If the rate of change in pressure is determined, the liquid to be dispensed, such as a liquid sample or a reagent solution, was normally collected on the chip 2, or the amount of the liquid to be dispensed was insufficient for some reason. It can be determined whether the sampling of the liquid to be dispensed has been abnormally performed, or the collection of the liquid to be dispensed has been abnormally performed because solids and insolubles are present in the liquid to be dispensed.

Here, when it is desired to distinguish whether the abnormality of the dispensing is caused by clogging of a solid substance or the like or the shortage of the amount to be dispensed, it is necessary to further terminate the suction operation or the suction operation of the dispensing pump. The absolute value of the suction pressure (gauge pressure) during normal suction after a certain period of time has elapsed is set as the pressure threshold, and this pressure threshold and the absolute value of the measured suction pressure (gauge pressure) are determined by the suction of the dispensing pump. The comparison may be made at the end of the operation or at the elapse of a fixed time from the end of the suction operation. If the absolute value of the measured suction pressure (gauge pressure) is larger than the pressure threshold, it is a dispensing abnormality due to clogging of a solid or the like, and if the measured absolute value of the suction pressure (gauge pressure) is smaller than the pressure threshold, Dispensing abnormality due to insufficient dispensed volume.

As can be seen from FIGS. 2 to 6, in the case where the liquid to be dispensed was collected normally, the absolute value of the rate of change of the pressure in the suction pressure curve (absolute pressure) after the dispensing pump 4 was stopped during suctioning Is a somewhat large value, and in the case where the amount of liquid to be dispensed is insufficient, the absolute value of the pressure change rate in the same suction pressure curve (absolute pressure) is a very small value, and there is no solid matter or insoluble matter. Even when the liquid to be dispensed is abnormally collected, the absolute value of the pressure change rate in the suction pressure curve is very small.

FIG. 7 shows, as a change curve, the results of measuring the suction pressure after the end of the suction operation of the dispensing pump 4 every 20 msec when the suction volume is 100 μl and the normal suction and the short sample. . The vertical axis corresponds to the suction pressure and corresponds to the absolute value of the gauge pressure. However, in FIG. 7, since the suction pressure uses the pressure signal 11, the unit is volt (V). From this result, it can be understood that the suction pressure change rate is larger in the case of normal suction than in the case of suction under the short sample during 80 msec from the end of the suction operation of the dispensing pump 4. And the same conclusion as above.

Here, based on the data of FIG. 7, from the time when 20 msec has elapsed since the end of the suction operation of the dispensing pump,
Table 1 below shows the pressure change rate (unit: V / s) at the time when 0 ms has elapsed. However, in Table 1, as in FIG. 7, the unit of the suction pressure is volt (V), which corresponds to the absolute value of the gauge pressure. The rate of pressure change is calculated to the second decimal place by rounding off the third decimal place.

[0044]

[Table 1]

As shown in Table 1, in the case of normal suction (data D1 to D4), the change rate of the suction pressure is 16.0 to 16.0.
22.0 V / s, abnormal suction (data D5
The rate of change of the suction pressure in the case of D7) is all 0.5 V / s. In this case, the threshold is set to 10.0 V / s, and 20 m from the end of the suction operation of the dispensing pump at the suction pressure of a certain sample.
If the rate of change from the time when seconds elapse to the time when the same 40 ms elapses is equal to or greater than the threshold value, normal suction is determined.

The time interval for obtaining the rate of change of the suction pressure is not limited to the time from 20 msec after the end of the suction operation of the dispensing pump to 40 msec as described above. From the end of the suction operation,
The time from when the dispensing pump completes the suction operation to the time when 20 ms elapses, or the time when 40 ms elapses. In these cases, a different threshold value suitable for these cases may be determined.

The absolute value of the pressure value (gauge pressure) of the suction pressure at the end of the suction operation of the dispensing pump 4 and the pressure value (gauge) of the suction pressure at the lapse of 60 msec from the end of the suction operation of the dispensing pump 4 The difference between the absolute values of the suction pressure and the suction pressure may be calculated by dividing the absolute value of the absolute value of the pressure by the time of 60 msec between the absolute values and calculating the rate of change of the suction pressure. This case is described in Table 2 below. The threshold value is set to 8.0 both when the suction amount is 20 μl and when the suction amount is 50 μl, but may be changed according to the suction amount.

[0048]

[Table 2]

Further, in Table 2 above, the dispensing pump 4
Instead of using the absolute value of the pressure value (gauge pressure) of the suction pressure at the end of the suction operation, the suction is performed using the absolute value of the pressure value (gauge pressure) 10 msec after the end of the suction operation of the dispensing pump 4. The rate of change of pressure may be determined. Therefore, the absolute value of the pressure value (gauge pressure) of the suction pressure 10 ms after the end of the suction operation of the dispensing pump 4 and the pressure value (gauge pressure) 60 seconds after the end of the suction operation of the dispensing pump 4 Pressure)
The difference between the absolute values of the pressures is taken, and the difference is divided by the time 50 ms between them to obtain the rate of change in pressure, and the result of comparison with the threshold is shown in Table 3 below. Also in this case, it is possible to determine not only the dispensing abnormality due to the clogging of the chip 2 but also the dispensing abnormality due to the shortage of the dispensed amount, so that more detailed determination can be advantageously performed. The threshold value is 50 μL even when the suction volume is 20 μL.
In the case of liter, both were set to 6.0, but may be changed according to the suction amount.

[0050]

[Table 3]

As shown in FIG. 9, as another embodiment, it is also possible to directly connect the dispensing pump and the tip without using a pipe. In this case, the dispensing pump 34 includes a syringe 34A, a piston 34B, a piston rod 34C, and a nozzle 34D, and the piston rod 34 is connected to pump driving means 35. In this case, the nozzle 34D
Has a nozzle head 34E at the end opposite to the end coupled to the syringe 34A, and this nozzle head 34E
Is connected to the chip 32. The pipe 33 is a syringe 34A
In the vicinity of the nozzle 34D on the side wall.

In this embodiment, unlike the first embodiment, the chip head moving means 14 connected to the chip head 2A of the first embodiment is different from the nozzle moving means 4 in the first embodiment.
4 is connected to the nozzle 34D, but the operation of the nozzle moving means 44 is not the tip head but the nozzle 34D.
It is the same as the chip head moving means 14 except that it acts on.

The case where the sample is dispensed from the sample container to each container of the immunoreaction cartridge has been described above. A predetermined amount of the reagent solution is dispensed from each reagent solution container to each container of the immunoreaction cartridge. It may be the case.

As described above, in the case of a suction abnormality due to an insufficient suction amount, the maximum value of the absolute value of the suction pressure (gauge pressure) is almost equal to that in the case of normal suction, so the measured suction pressure (gauge pressure) Cannot be accurately determined by a method of comparing the absolute value of the pressure with the pressure threshold value determined based on the absolute value of the suction pressure (gauge pressure) in the case of normal suction, but the measured or measured / calculated suction pressure Change rate of absolute value of (gauge pressure) and suction pressure (gauge pressure) for normal suction
If the method is based on comparing the threshold value of the change rate determined based on the change rate of the absolute value of, this can be accurately determined. Therefore, if the detection method of the present invention described above,
Not only the suction abnormality due to the clogging of the chip 2 but also the suction abnormality due to the shortage of the suction amount can be determined, so that more detailed determination can be advantageously performed.

[0055]

As described above, according to the present invention, the pressure in the suction channel is detected, and the rate of change is calculated from the detected pressure.
Since this is compared with a predetermined threshold value, it is possible to determine not only a suction abnormality due to clogging but also a suction abnormality due to a shortage of suction amount, so that more detailed determination can be advantageously performed.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a main configuration of a dispensing device according to a first embodiment of the present invention.

FIG. 2 is a pressure waveform diagram in which a change in suction pressure is measured when a suction volume is 100 μl and dispensing is performed normally.

FIG. 3 is a pressure waveform diagram in which a change in suction pressure is measured when a suction volume is 50 μl and a normal dispensing is performed.

FIG. 4 is a pressure waveform diagram measuring a change in suction pressure when a suction volume is 20 μl and a normal dispensing is performed.

FIG. 5 is a pressure waveform diagram in which a change in suction pressure is measured when the dispensing is performed in a state where the dispensing amount is insufficient with a suction volume of 50 μl.

FIG. 6 is a pressure waveform diagram illustrating a change in suction pressure when the suction capacity is 20 μl and clogging occurs.

FIG. 7 is a pressure change diagram showing a change in suction pressure collected when the suction volume is 100 μl and the dispensing is performed normally and when the amount to be dispensed is insufficient.

FIG. 8 is a schematic diagram illustrating a configuration of a dispensing pump according to the first embodiment.

FIG. 9 is a schematic diagram showing a configuration of a dispensing pump according to another embodiment.

[Explanation of symbols]

 Reference Signs List 1 dispensing device 2 tip 2A tip head 3 piping 4 dispensing pump 4A syringe 4B piston 4C piston rod 4D nozzle 5 pump driving means 6 control unit 7 pump control signal 8 pressure sensor 9 pressure signal 10 amplifier 11 pressure signal 12 A / D Converter 13 CPU 14 Chip head moving means 15 Chip head moving signal 32 Chip 33 Piping 34 Dispensing pump 34A Syringe 34B Piston 34C Piston rod 34D Nozzle 34E Nozzle head 35 Pump driving means 44 Nozzle moving means AA External direction BB Internal direction E Suction operation At end S At start of suction operation

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Ryoichi Hasegawa Inventor F-term in Fujirebio Co., Ltd. 2-62-5 Nihonbashihamacho, Chuo-ku, Tokyo 2G058 AA09 BB09 BB15 CC08 EA02 EB01 ED22 FA01 GB06 GB10

Claims (7)

[Claims] 1. A method for detecting clogging of a suction flow channel or insufficient suction volume performed when a predetermined amount of a sample liquid is suctioned; detecting a pressure in the suction flow channel after stopping the suction operation of the sample liquid; Calculating the rate of change from the detected pressure;
Comparing the calculated change rate with a predetermined threshold value to detect clogging of the suction channel or insufficient suction amount;
A method for detecting clogging of the suction channel or insufficient suction volume. 2. The method according to claim 1, wherein the predetermined threshold value is determined in accordance with a suction amount of the sample liquid. 3. The change rate is a change rate between a time when the suction operation is stopped and a time when a predetermined time elapses from the time when the suction operation is stopped,
3. The method according to claim 1, wherein the suction flow path is clogged or the suction amount is insufficient. 4. The suction flow path according to claim 1, wherein the change rate is a change rate between two predetermined points after a lapse of a predetermined time from the stop of the suction operation. Detection method. 5. A pressure sensor for detecting a pressure in a suction flow path for sucking a sample liquid; a calculation unit for calculating a change rate from the detected pressure; a storage unit for storing a threshold value of the calculated change rate; A comparison unit configured to compare the change rate with a threshold value stored in the storage unit; 6. The sample liquid suction device according to claim 5, further comprising a calculation unit that calculates the threshold value in accordance with a suction amount of the sample liquid. 7. A sample liquid suction apparatus according to claim 5, wherein: a holding section for holding a container containing the sample liquid; and the suction channel and the holding section are relatively moved. A dispensing device.