JP2008298755A - Medical photometer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a medical photometer capable of reducing effect of reaction liquid and cleaning liquid of a previous time, in other words, capable of reducing carry-over effect. <P>SOLUTION: A change-over valve 19 is provided in a flow passage between a specimen suction nozzle 10A and a flow cell 7. The change-over valve 19 switches over the flow passage between the specimen suction nozzle 10A and an air suction nozzle 10B. A micro computer 15 controls the switch-over valve 19 and switches over the flow passage between the specimen suction nozzle and the air suction nozzle and forms a dummy layer in which the reaction liquid and air alternately arranged in the flow passage. The switch valve 19 is capable of switching the flow passage between a cleaning liquid suction nozzle 10C capable of sucking the cleaning liquid in the flow passage and itself. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a medical photometer that performs qualitative / quantitative analysis of biological samples such as blood and urine, and in particular, a sample solution is used to manually aspirate each sample and then react the sample with a reagent. The present invention relates to a small-sized medical photometer that detects an analysis target component in a sample by detecting a change in color of the sample.

  Conventionally, biochemical analysis, which was confirmed as a concentration by confirming the color change of the reaction solution with the naked eye using a colorimetric table (color chart), is due to the advent of an automatic analyzer that can quantitatively measure absorbance changes with a photometer, High measurement reproducibility and analysis speed can be obtained. Such an automatic analyzer can obtain accurate analysis data even by an inexperienced laboratory technician. Such analyzers can be broadly divided into automatic analyzers that automatically dispense, stir, and measure samples and reagents into reaction vessels, and machines that perform only measurements, and dispense and stir samples and reagents. It is divided into medical photometers performed by the operator. The latter is used in small hospitals, clinics, etc., and is used for backup when the automatic analyzer is stopped or as a reference for the automatic analyzer. For example, a medical photometer is known that uses a sample sipper to measure the absorbance by sucking the reaction solution directly into a flow cell (see, for example, Patent Document 1).

  The medical photometer reports the measurement result quantitatively, but on the other hand, if the state of the analyzer cannot be maintained constant, an erroneous analysis result may be obtained. For example, since measurement using a flow cell is performed by continuously sucking the reaction solution into the tube, the reaction solution from the previous measurement and the reaction solution from the next measurement are in direct contact with each other in the flow cell. The reaction solution at the next measurement may be affected by the reaction solution at the previous measurement. For this reason, in the measurement, an attempt is made to flow a sufficient amount of the reaction solution or to stop the measurement once and wash it with a cleaning solution.

  In the former case, since a large amount of reaction solution is required, the amount of sample and the amount of reagent increase, resulting in an increase in the burden on the patient and an increase in running costs, which is not an appropriate solution. In the latter case, a method of automatically cleaning with a cleaning liquid is known (see, for example, Patent Document 2). In Patent Document 2, as a flow cell cleaning mechanism, a flow cell cleaning device that supplies a cleaning liquid and means for determining the state of the flow cell based on the amount of light absorbed by the flow cell supplied with the cleaning liquid are provided. With the thing of patent document 2, the washing | cleaning operation | movement before a measurement was automated, and it became realizable to diagnose the state of a cell. However, this method has a problem that the detergent and the reaction liquid are mixed in the flow cell and the reaction liquid is diluted by the detergent. This is because the cleaning is completed with the cleaning liquid filled in the tube, and the reaction liquid is continuously sucked and photometrically measured as it is.

  On the other hand, there is known one that sucks a dummy layer in which a small amount of sample and air are alternately arranged before sucking the sample (see, for example, Patent Document 3).

JP 2005-345173 A Japanese Patent Laid-Open No. 4-125446 JP-A-7-159415

  However, the device described in Patent Document 3 is applied not to a medical photometer but to an automatic analyzer. That is, as shown in FIG. 2 of Patent Document 3, an autosampler is used, a suction nozzle is inserted into the sample, a small amount of sample in the dummy layer is sucked, and then the suction nozzle In a state where the sample is pulled out from the sample, air in the dummy layer is sucked and repeated, thereby forming a dummy layer in which a small amount of sample and air are alternately arranged. Since the automatic analyzer uses an autosampler that can automatically move the nozzle up and down, the dummy layer as described above can be formed. However, the medical photometer does not have an autosampler, and the analyst's Since only the sample shipper that sucks the sample by the switch operation is provided, a dummy layer in which a small amount of sample of 50 μl and air are alternately arranged as described in Patent Document 3 is formed by the switch operation of the analyst. Is not possible.

  An object of the present invention is to provide a medical photometer that can reduce the influence of the previous reaction solution and cleaning solution, that is, the effect of carryover.

(1) In order to achieve the above object, the present invention provides a medical photometer for measuring the absorbance of a reaction liquid sucked into a flow cell from a sample suction nozzle, wherein the flow path between the sample suction nozzle and the flow cell A switching valve for switching a flow path between the sample suction nozzle and an air suction nozzle capable of sucking air into the flow path, and controlling the switching valve to control the sample suction nozzle and the air The flow path is switched between the suction nozzle and a control means for forming a dummy layer in which the reaction liquid and air are alternately repeated in the flow path.
With this configuration, the influence of carryover can be reduced in the medical photometer.

  (2) In the above (1), preferably, the switching valve further includes a cleaning liquid suction nozzle capable of sucking a cleaning liquid into the flow path, and a flow path between the sample suction nozzle and the air suction nozzle. It can be switched.

  (3) In the above (1), preferably, the control means sucks air from the sample suction nozzle after completion of suction of the reaction liquid.

  According to the present invention, in the medical photometer, the influence of the previous reaction liquid or cleaning liquid can be reduced, that is, the influence of carry-over can be reduced.

Hereinafter, the configuration and operation of a medical photometer according to an embodiment of the present invention will be described with reference to FIG.
FIG. 1 is a system block diagram showing the configuration of a medical photometer according to an embodiment of the present invention.

  The medical photometer includes a photometric measurement unit, a mechanism unit, a signal processing unit, a control unit, a display unit, an input unit, and an external output unit. The photometric measurement unit is composed of a light source lamp 1, a mirror 2, a slit 3, a grating 4, a mirror 5, a half mirror 6, a flow cell 7, a reference detector 12, and a cell detector 13. Has been. The light of the optical axis 14 projected from the light source lamp 1 is applied to the grating 4 through the mirror 2 and the slit 3 and is dispersed. The grating 4 is rotated by a pulse motor, and a wavelength necessary for analysis can be arbitrarily selected. The light on the optical axis 14 separated from the grating 4 passes through only a predetermined wavelength selected by the slit 3. The light that has passed through the slit 3 is irradiated onto the mirror 5, divided into two optical paths of sample light and reference light by the half mirror 6, and converted into an electrical signal by the cell detector 13 and the reference detector 12. The A flow cell 7 is disposed between the half mirror 6 and the cell detector 13. The flow cell 7 is made of quartz and transmits light well. The sample passes through the flow cell 7 as described later. The light of the optical axis that passes through the flow cell 7 is detected by the cell detector 13, enters the reference detector 12 directly from the half mirror 6, and is detected by the reference detector 12. By comparing the sample signal detected by the cell detector 13 with the reference signal detected by the reference detector 12, the component to be analyzed in the sample sucked into the flow cell 7 is measured.

  The mechanism unit includes a pump 8, a reaction vessel 9A containing the reaction liquid 9, suction nozzles 10A, 10B, and 10C, a waste liquid tank 11, a switching valve 19, a suction start switch 20, and a cleaning liquid tank 22A. Composed. The switching valve 19 switches the flow path between the sample suction nozzle 10A for sucking the sample, the air suction nozzle 10B opened to the atmosphere, and the cleaning liquid suction nozzle 10C for sucking the cleaning liquid. By rotating the pump 8, the sample (reaction liquid) is sucked from the suction nozzle 10A, the air is sucked from the suction nozzle 10B, or the cleaning liquid is sucked from the suction nozzle 10C. The sucked sample, cleaning liquid, and air are conveyed to the waste liquid tank 11 through the flow cell 7.

  The control unit is composed of a microcomputer 15. The microcomputer 15 controls a pulse motor that rotates the grating 4, a pump 8, and a switching valve 19. The start signal of the suction start switch 20 is input to the microcomputer 15, and based on this start signal, the microcomputer 15 pump 8 and the switching direction of the switching valve 19 are controlled.

  The signal processing unit includes a LOG converter, a preamplifier, and a microcomputer 15 (not shown). The sample signal for the sample light detected by the cell detector 13 and the reference signal for the reference light detected by the reference detector 12 are logarithmically converted by a LOG converter and further amplified by a preamplifier. The data is taken into the microcomputer 15 through A / D conversion. The microcomputer 15 calculates the absorbance and concentration of the analysis target component in the sample based on the sample signal and the reference signal.

  The display unit includes a display screen 16 and displays analysis items, analysis results, and the like. The input unit includes an operation panel 17 and inputs various information such as analysis parameters. The external output unit includes a printer 18 that prints measurement results and the like, and a buzzer 21 that emits sound and notifies the end of suction of the reaction liquid.

  In the medical photometer configured as described above, the control function of the switching valve 19 will be described. The valve control function includes 1) standard mode (dummy suction mode), 2) first carryover reduction mode, 3) second carryover reduction mode, and 4) simultaneous reproducibility mode. These modes can be selected by the operator operating the operation panel 17. In addition, the sample suction nozzle 10A is inserted into the container 9A containing the reaction liquid 9, and the operator presses the suction start switch 20 while the tip of the sample suction nozzle 10A is in contact with the reaction liquid 9. The mode starts operating.

  1) The standard mode (dummy suction mode) is used when measuring general colorimetric items. In this mode, the reaction solution is divided and sucked for dummy suction and measurement.

  2) Carryover reduction 1st mode is useful control for the measurement in which slight carryover such as tumor marker is concerned about the measurement result. By increasing the number of dummy suctions of air and reaction liquid compared to the standard mode, it is possible to perform measurement in a state where the influence of carryover is reduced.

  3) The carryover reduction second mode is a control useful for measurement in which slight carryover such as a tumor marker is likely to affect the measurement result, like the first carryover reduction mode. Similar to the first mode of carryover reduction, it is possible to perform measurement in a state where the influence of carryover is reduced by increasing the number of dummy suctions of air and reaction liquid and flowing the cleaning liquid as compared with the standard mode.

  4) The simultaneous reproducibility mode is a control in which carryover between samples can be ignored, for example, when the same sample is continuously measured in reagent examination or the like. When this mode is selected, dummy suction between the same reaction solutions is not performed.

  First, the measurement procedure when the standard mode (dummy suction mode) is selected will be described.

  (1) The operator sets the reaction liquid 9 in the sample suction nozzle 10A and presses the suction start switch 20. (2) The microcomputer 15 controls the switching valve 19 to switch the switching valve 19 in the direction of the sample pulling nozzle 10 </ b> A and rotate the peristaltic pump 8 in the forward direction, thereby sucking 100 μL of the reaction solution 9. As will be understood from the description of (10) described later, since 100 μL of air is sucked at the end of the previous sample measurement, 100 μL of the reaction solution is sucked after 100 μL of air. Become. (3) When the suction of 100 μL of the reaction solution is completed, the microcomputer 15 controls the switching valve 19 to switch the switching valve 19 in the direction of the air suction nozzle 10B. The peristaltic pump 8 continues to rotate and sucks 100 μL of air from the air suction nozzle 10B. (4) The microcomputer 15 controls the switching valve 19 to switch the switching valve 19 in the direction of the sample pulling nozzle 10 </ b> A, and sucks 100 μL of the reaction solution 9.

  (5) The above operations (3) and (4) are repeated four times. (6) The microcomputer 15 controls the switching valve 19 again, switches the switching valve 19 in the direction of the air suction nozzle 10B, and sucks 100 μL of air. (7) Finally, the microcomputer 15 controls the switching valve 19 to switch the switching valve 19 in the direction of the sample pulling nozzle 10 </ b> A, suck 500 μL of the reaction solution for measurement, and measure the light at an arbitrary timing. (8) Output the end of suction on the screen or buzzer. (9) According to the signal, the operator removes the reaction liquid 9 from the sample suction nozzle 10A. (10) Before the measurement of the next reaction solution, 100 μL of air is automatically sucked. In addition, when continuing measurement continuously, (1) to (10) are repeated.

  Through the control operation described above, “100 μL of air” (the one sucked during the previous measurement) — “(100 μL of reaction solution) — (Air 100 μL) − (Reaction solution 100 μL) − (Air 100 μL) − (Reaction solution 100 μL) − (Air 100 μL) − (Reaction solution 100 μL) − (Air 100 μL) − (Reaction solution 100 μL) − (Air 100 μL) ”) A layer of “dummy suction” − “(reaction liquid 500 μL)” (for measurement) − “air 100 μL” is continuously formed.

  In this way, by flushing the dummy layer in which 100 μL of air and 100 μL of reaction solution are alternately repeated one after another, the reaction solution at the time of the previous measurement remaining in the flow channel is flowed out, and the reaction sucked last for measurement The absorbance of the reaction solution can be measured without being affected by carryover.

  Next, a measurement procedure when the carryover reduction first mode is selected will be described. In this mode, the number of repetitions in (5) of the standard mode (dummy suction mode) is different, and is to increase from 4 times to 7 times. As a result, in the flow path (tube) of the sample suction nozzle 10A-flow cell 7-waste liquid tank 11, “100 μL of air” (those sucked during the previous measurement) — “(100 μL of reaction solution) — (100 μL of air) )-(Reaction solution 100 μL)-(Air 100 μL)-(Reaction solution 100 μL)-(Air 100 μL)-(Reaction solution 100 μL)-(Air 100 μL)-(Reaction solution 100 μL)-(Air 100 μL)-(Reaction solution 100 μL) )-(Air 100 μL)-(Reaction solution 100 μL)-(Air 100 μL)-(Reaction solution 100 μL)-(Air 100 μL) ”(Dummy suction)-“ (Reaction solution 500 μL) ”(for measurement)-“ Air 100 μL ” Are continuously formed.

  In this way, by increasing the number of times that 100 μL of air and 100 μL of reaction solution are alternately repeated and flushing the dummy layer one after another, it is possible to measure that a slight carryover such as a tumor marker may affect the measurement result. On the other hand, the reaction solution remaining in the flow path at the time of the previous measurement flows out, and the reaction solution sucked last for measurement is not affected by carryover, and the original absorbance measurement of the reaction solution can be realized. .

  Next, a measurement procedure when the carryover reduction second mode is selected will be described. In this mode, 100 μL of the reaction solution and 100 μL of the cleaning solution are added before (2) of the standard mode (dummy suction mode), and the number of repetitions in (5) of the standard mode (dummy suction mode) is added. There is a difference from 4 times to 7 times. In order to suck the cleaning liquid, the microcomputer 15 controls the switching valve 19 to switch the switching valve 19 in the direction of the cleaning liquid pulling nozzle 10C and rotate the peristaltic pump 8 in the forward direction, thereby sucking 100 μL of the cleaning liquid 22. .

  As a result, in the flow path (tube) of the sample suction nozzle 10A-flow cell 7-waste liquid tank 11, “air 100 μL” (those sucked during the previous measurement) − “(reaction liquid 100 μL) − (cleaning liquid 100 μL) )-(Reaction solution 100 μL)-(Air 100 μL)-(Reaction solution 100 μL)-(Air 100 μL)-(Reaction solution 100 μL)-(Air 100 μL)-(Reaction solution 100 μL)-(Air 100 μL)-(Reaction solution 100 μL) )-(Air 100 μL)-(Reaction solution 100 μL)-(Air 100 μL)-(Reaction solution 100 μL)-(Air 100 μL)-(Reaction solution 100 μL)-(Air 100 μL) ”(Dummy suction)-“ (Reaction solution 500 μL ) ”(For measurement) —“ 100 μL of air ”layer is formed continuously.

  In this way, by increasing the number of times that 100 μL of air and 100 μL of reaction solution are alternately repeated, the dummy layer is pushed away one after another, and the washing solution is first passed, so that a slight carryover such as a tumor marker affects the measurement result. Even for measurements where there is a concern, the reaction liquid remaining in the flow path at the time of the previous measurement will flow out, and the reaction liquid aspirated last for measurement will not be affected by carryover. The original absorbance measurement can be realized. Although the cleaning liquid is used, it is possible to prevent the cleaning liquid from remaining and diluting the reaction liquid by repeating the dummy suction after flowing the cleaning liquid.

Next, a measurement procedure when the simultaneous reproducibility mode is selected will be described.
(1) The operator sets the reaction liquid 9 in the sample suction nozzle 10A and presses the suction start switch 20. (2) The microcomputer 15 controls the switching valve 19, switches the switching valve 19 in the direction of the sample pulling nozzle 10A, and rotates the peristaltic pump 8 in the forward direction, thereby sucking 500 μL of the reaction liquid 9 and any timing. Measure the light with. (3) Output the end of suction on the screen or buzzer. (4) According to the signal, the operator removes the reaction liquid 9 from the sample suction nozzle 10A. (5) 100 μL of air is automatically sucked before measuring the next reaction solution. When continuing measurement continuously, (2) to (5) are repeated. In the above example, an air dummy layer is automatically sandwiched at the end of measurement (simultaneous reproducibility mode).

As described above, carryover between the reaction solution and the reaction solution, between the reaction solution and the reaction solution, and between the reaction solution and the reaction solution, and between the reaction solution and the reaction solution are reduced. can do. At this time, the air layer and the cleaning layer are not formed using an autosampler, but a switching valve for switching the flow path is provided between the sample suction nozzle of the sample shipper and the flow cell, and the air is controlled by controlling the switching valve. Alternatively, since the cleaning liquid is formed, the medical photometer can be easily realized.

It is a system block diagram which shows the structure of the medical photometer by one Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Light source lamp 2, 5 ... Mirror 3 ... Slit 4 ... Grating 6 ... Half mirror 7 ... Flow cell 8 ... Pump 9 ... Reaction liquid 9A ... Reaction liquid container 10A ... Sample suction nozzle 10B ... Air suction nozzle 10C ... Cleaning liquid suction nozzle 11 ... Waste liquid tank 12 ... Reference detector 13 ... Cell detector 14 ... Optical axis 15 ... Microcomputer 16 ... Screen 17 ... Operation panel 18 ... Printer 19 ... Switching valve 21 ... Buzzer 22 ... Cleaning liquid 22 ... Cleaning liquid tank

Claims (3)

A medical photometer that measures the absorbance of a reaction solution sucked into a flow cell from a sample suction nozzle,
A switching valve that is provided in a flow path between the sample suction nozzle and the flow cell and switches the flow path between the sample suction nozzle and an air suction nozzle capable of sucking air into the flow path;
Control means for controlling the switching valve to switch the flow path between the sample suction nozzle and the air suction nozzle, and forming a dummy layer in which the reaction liquid and air are alternately repeated in the flow path; A medical photometer characterized by comprising: The medical photometer according to claim 1, wherein
The switching valve is further capable of switching the flow path between a cleaning liquid suction nozzle capable of sucking a cleaning liquid into the flow path, and the sample suction nozzle and the air suction nozzle. . The medical photometer according to claim 1, wherein
The control means sucks air from the sample suction nozzle after completion of suction of the reaction solution.

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