JP4696934B2 - Analysis equipment - Google Patents

Description

  The present invention relates to an analyzer, and more particularly to an analyzer using an LED (Light Emitting Diode) as a light source for measurement.

For example, in order to reduce the size of an analyzer that performs analysis by measuring the transmitted light of a liquid containing a sample and a reagent, an LED may be used as the light source. For example, in Japanese Patent Application Laid-Open No. 2004-101295, a color reaction between a reagent and a sample in a cuvette is configured to perform transmission photometry using a light emitting element using an LED, and the apparatus is miniaturized. An analyzer for performing accurate photometry by stabilizing the emission spectrum and emission intensity due to changes and current changes is disclosed. Specifically, an automatic analyzer that mixes a reagent and sample liquid in a cuvette and measures the color change of the reagent to analyze the sample component can mount a plurality of sample containers and cuvettes containing the sample liquid. It includes a sample tray and a photometric unit consisting of a light-emitting element and a light-receiving element using LEDs that transmit and measure the color change of the reagent and sample liquid in the cuvette. The light-emitting element of the photometric unit is attached to a member with a large heat capacity The temperature is adjusted and the constant current drive circuit lights up.
JP 2004-101295 A

  As described above, the conventional technique solves the change in the emission intensity due to the temperature change, which becomes a problem when the LED is used as the light source, by inserting the LED into a member having a large heat capacity. However, the technique described in this publication uses a cuvette having a rectangular cross section, and depending on characteristics such as the viscosity of the liquid, there is a problem in cleaning that makes it difficult to remove the liquid adhering to the vicinity of the corner of the cuvette.

  In order to solve this problem of washing, it is conceivable to use a container having a round cross section. However, there is no disclosure in the above-mentioned gazette about a problem newly generated in such a case. .

  Accordingly, an object of the present invention is to provide a small analyzer that enables stable measurement using a liquid holding portion having a round cross section and an LED as a light source for measurement.

  Another object of the present invention is to provide a small analyzer that enables stable and highly accurate measurement using a liquid holding section having a round cross section and an LED as a light source for measurement.

  Furthermore, another object of the present invention is to provide a small analyzer for performing stable and highly accurate measurement at high speed using a liquid holding part having a round cross section and an LED as a light source for measurement. It is.

The analyzer according to the present invention, for holding a liquid to be measured, section comprises a liquid holding portion of the round, and a reaction tank for and move are thermostatic are reaction vessel and thermally coupled LED A light source for making the intensity of light emitted from the LED light source uniform with respect to the light source, the light receiving surface of the liquid holding unit, and the light transmitted through the liquid holding unit that has moved to the exit position of the light guiding unit It has a light measurement unit that measures the intensity during the constant speed movement of the liquid holding unit, and a processing unit that performs processing based on a signal from the light measurement unit.

  In this way, in the conventional technology, it is difficult to perform stable measurement when using an LED having a nonuniform light intensity on the light receiving surface and a liquid holding portion having a round cross section because the light emitting surface is small. It is possible to solve unknown problems and obtain measurement data with little variation. That is, highly accurate measurement and analysis are possible. In addition, it is also possible to suppress measurement data variation and perform high-speed processing by performing measurement while moving a reaction tank having a liquid holding section having a round cross section at a constant speed.

  In addition, the structure mentioned above may scatter the light ray from a LED light source. According to such a configuration, the density of light rays on the light receiving surface of the liquid holding unit can be made uniform, so that measurement with higher accuracy can be performed.

  Moreover, you may make it comprise the said light guide part with the cylinder which has a glossy inner wall. In this way, since the light beam output from the LED light source is reflected by the inner wall of the cavity, the intensity of the light beam with respect to the light receiving surface is made uniform at the exit of the light guide unit. It should be noted that the same effect can be obtained even if the light guide portion is formed of an optical fiber.

  Further, the processing unit described above may perform processing for detecting the peak of the signal. By doing in this way, when the reaction vessel is moved at a constant speed, efficient and highly accurate peak detection is enabled.

  Further, the light guide unit and the LED light source holding unit may be integrally formed as a measurement unit. And this measurement part may be made to be connected with the thermostat which makes the reaction tank thermostatic. If it does in this way, the temperature change of a LED light source holding part can be controlled, and the thermal problem of LED can be solved stably.

  Furthermore, the liquid holding portion described above may be made of polypropylene. Such a material is used because it is easy to clean, has high durability, and has water repellency, and can cope with a small amount of liquid to be measured.

  Further, the LED light source may include a plurality of LEDs having different wavelengths. And you may make it provide a light guide part and a light measurement part corresponding to each LED. In this way, it can be applied to various analyses.

  Moreover, you may make it use the analyzer which concerns on this invention in order to measure the light absorbency of a to-be-measured liquid. If it is used for such an application, an accurate absorbance analysis can be performed.

  Furthermore, the analyzer according to the present invention may be used for performing fecal occult blood analysis. If it is used for such applications, it becomes possible to analyze blood components in feces with high accuracy.

  Note that the movement of the reaction vessel, the identification of the liquid holding unit, the correspondence between the processing result of the processing unit and the identification information of the liquid to be measured in the liquid holding unit, etc., according to the instruction from the control device that executes the control program Controlled. Such a control program is stored in a storage medium or storage device such as a flexible disk, a CD-ROM, a magneto-optical disk, a semiconductor memory, or a hard disk. In some cases, digital signals are distributed over a network. Note that data being processed is temporarily stored in a storage device such as a computer memory.

  According to the present invention, it is possible to perform stable measurement using a liquid holding portion having a round cross section and an LED as a light source for measurement.

  In addition, according to another aspect of the present invention, it is possible to perform stable and highly accurate measurement using a liquid holding unit having a round cross section and an LED as a light source for measurement.

  Furthermore, according to another aspect of the present invention, stable and highly accurate measurement can be performed at high speed by using a liquid holding portion having a round cross section and an LED as a light source for measurement.

  FIG. 1 shows a perspective view of an automatic analyzer according to an embodiment of the present invention. In addition, in order to show the structure which concerns on this Embodiment, the state which removed the normally attached cover is shown. Although the automatic analyzer 100 according to the present embodiment has various functions, the parts related to the present embodiment include the puncture unit 1, the support column 2 of the puncture unit 1, the suction nozzle 3, the stool collection container A fixed sample 4, a column 5 of the fixed unit 4, a stool collection container transport unit 6, a reaction unit 7 and a suction sample provided in the reaction unit 7 (filtered stool suspension. , Also referred to as a sample.) The injection hole 8 to the analysis container (also referred to as a liquid holding unit) for analysis, the nozzle cleaning unit 9, the rail 10 on which the transport unit 6 moves, and the automatic analyzer 100 are controlled. Information processing unit 11, printer 12, display unit 13, barcode reader 14 for reading a barcode attached to a stool collection container, reagent cold storage unit 16, and reagent for injecting a reagent held in reagent cold storage unit 16 into an analysis container Dispensing unit 15 for sample injected into analysis container Photometry unit 17 performs measurements, having such cleaning unit 18 for cleaning the analysis container.

  Here, an outline of the operation of the automatic analyzer 100 shown in FIG. 1 will be described. In response to a user instruction to the touch panel display unit 13, the information processing unit 11 controls each unit to perform the following operations. That is, the transport unit 6 on which one or more stool collection containers are placed moves along the rail 10 to a position where the fixing unit 4 is installed. In addition, when moving, the barcode reader 14 reads the barcode attached to the stool collection container and outputs it to the information processing unit 11. The information processing unit 11 retains the barcode data from the barcode reader 14 and associates it with the result of analysis processing to be performed later. When the transport unit 6 moves the stool collection container to be analyzed this time below the fixing unit 4, the support column 5 of the fixing unit 4 is lowered and the upper part of the stool collection container is fixed. Next, the support column 2 of the puncture unit 1 is rotated so that the tip of the suction nozzle 3 is positioned at the center of the upper end of the stool collection container, and the support column 2 is lowered to perform a drilling operation, a suction operation, and the like. After the suction, the column 2 is pulled up and rotated so that the tip of the suction nozzle 3 is positioned at the center of the injection hole 8. In the reaction unit 7, the analysis container for analyzing the current suction sample is rotated to the position of the injection hole 8. Thereafter, the sample sucked by the suction nozzle 3 is injected into the analysis container of the reaction unit 7 through the injection hole 8 together with a predetermined amount of the first reagent. (By this step, it is possible to omit the subsequent internal cleaning step since the internal cleaning of the suction nozzle has been substantially performed.) Along with the predetermined amount of the first reagent, the analysis container into which the sample has been injected Then, the reagent held in the reagent cold storage unit 16 is injected by the reagent dispensing unit 15, the measurement is performed by the photometric unit 17, and the measurement result is output to the information processing unit 11. The information processing unit 11 performs an analysis process based on the measurement result, associates the analysis result with the barcode data read above, stores it in the storage device, and displays it on the display unit 13. If there is an instruction from the user, the analysis result is printed out from the printer 12. In addition, the cleaning unit 18 cleans the used analysis container of the reaction unit 7 at an appropriate timing.

  Hereinafter, the reaction unit 7 and the photometry unit 17 will be described in detail with reference to FIGS. FIG. 2 shows a perspective view when the cover of the reaction section 7 is removed and the angle is changed. As shown in FIG. 2, the reaction unit 7 includes, for example, a reaction tank (hidden by a cover) in which cells serving as 45 liquid holding units are provided in the cylindrical portion for every 8 ° of the central angle of the cylinder, The temperature of the reaction tank is kept constant by sandwiching the reaction tank cover 73 having a cell hole 73a provided at the upper part of the cell and the reaction tank cover provided with the cell under the reaction tank cover 73. A constant temperature unit 71 having a heater for the rotation, a rotary shaft 72 connected to a motor (not shown) for rotating the reaction tank at a constant speed, and the rotary shaft 72 and the reaction tank are connected to each other. And a rotation connecting portion 74 that rotates the reaction vessel in accordance with the rotation. The rotary connecting portion 74 includes a disc-shaped horizontal plate 74a connected to the rotary shaft 72 and a cylindrical vertical wall 74b connected to the horizontal plate 74a.

  The number of cells is not limited to 45, but an appropriate number can be determined from the size, strength, measurement efficiency, etc. of the cylindrical reaction tank.

  The photometric unit 17 is connected to the thermostatic unit 71 by cutting out a part of the thermostatic unit 71, and the thermostatic unit 71, the reaction vessel, and the photometric unit 17 are thermally coupled. That is, the term “thermally coupled” means that the thermostat 71 is coupled so that the reaction vessel and the photometry unit 17 are thermostated at the same time, and the thermostat 71, the reaction vessel, and the photometry unit 17 are directly connected. As a result, the heat from the constant temperature unit 71 may be conducted to the reaction vessel and the photometry unit 17, but the heat from the constant temperature unit 71 passes through another heat conductive medium even if they are not directly connected. The case where the reaction vessel and the photometric unit 17 are brought to a constant temperature by being conducted to the photometric unit 17 is also included. The details of the photometry unit 17 will be described with reference to FIGS.

  Next, the constant temperature part 71 is outlined using the perspective view of FIG. The thermostat 71 includes a first thermostatic wall 71a and a second thermostatic wall 71b provided outside the moving path 71f along which the reaction tank moves, and a third thermostatic wall 71c and a fourth thermostatic wall provided inside the moving path 71f. And a wall 71d. The second and third constant temperature walls 71b and 71c are embedded with a heater or the like (not shown) or connected to the heater, so that the temperature of the reaction vessel is constant. The first and fourth heat insulating walls 71a and 71d are formed using a heat insulating material such as polyurethane, for example. Further, the first and fourth heat retaining walls 71a and 71d and the second and third constant temperature walls 71b and 71c are provided with notches 71e for connecting the photometry unit 17.

  In the example of FIG. 3, the second and third constant temperature walls 71b and 71c, the first and fourth constant temperature walls 71a and 71d, and a total of four walls form the constant temperature part 71, but sandwich the reaction tank. If so, it may be configured by two constant temperature walls. Moreover, as long as the temperature of the reaction vessel can be kept constant, it may be configured by only one constant temperature wall (for example, the constant temperature wall 71b). Further, the first and fourth heat retaining walls 71a and 71d may be made to function as constant temperature walls by embedding a heater or the like or connecting to the heater. Further, the position of the notch 71e can be moved according to the installation position of the photometry unit 17. In addition, when the size of the photometry unit 17 is sufficiently small compared to the size of the constant temperature unit 71 (that is, if the photometric unit 17 can be embedded in the constant temperature unit 71), the second and second The notch 71e may be provided only in the three constant temperature walls 71b and 71c, and the photometry unit 17 may be installed in the notch. The installation position of the photometry unit 17 is affected by the installation position of the cleaning unit 18 and other functions, but may basically be any one of the cylindrical thermostatic unit 71.

  Next, the structure of the reaction tank and the mechanism for rotating the reaction tank will be described with reference to FIG. FIG. 4 is a schematic cross-sectional view of a plane that passes through the center of the rotary shaft 72 and cuts the horizontal plate 74a of the rotary connecting portion 74 vertically. In addition, illustration is abbreviate | omitted about the component of the constant temperature part 71. FIG. The rotary shaft 72 is connected to the horizontal plate 74a of the rotary connecting portion 74 by a fixed portion 72a, and is further supported by the support portion 78 so as to rotate vertically with respect to the substrate 81 of the reaction portion 7. The rotating shaft 72 is connected to the motor 80 via the connecting portion 79, and the rotation of the motor 80 is controlled by the information processing unit 11 that operates as a control unit. The connecting portion 79 is covered with a cover 82. Further, the vertical wall 74b of the rotary connecting portion 74 is coupled to a donut-shaped connecting plate 77 centered on the center of the rotating shaft 72 and separated by two concentric circles separated by a predetermined distance. The connecting plate 77 is coupled to a donut-shaped cover 73 centered on the center of the rotating shaft 72 and separated by two concentric circles separated by a predetermined distance. A reaction tank 75 is coupled to the lower portion of the cover 73, and a cell 76 is provided in accordance with the position of the cell hole 73 a of the cover 73.

  The reaction tank 75 has a cylindrical shape centered on the center of the rotating shaft 72, the third constant temperature wall 71 c and the fourth heat insulation wall 71 d provided in the part B, and the first heat insulation provided in the part A. It is sandwiched between the wall 71a and the second constant temperature wall 71b, and is thermally coupled to the constant temperature portion 71. Although the figure is drawn symmetrically about the rotation axis 72, in the example described above, the number of cells is 45, which is an odd number. Therefore, the horizontal plate of the rotation connecting portion 74 passes through the rotation axis 72. When 74a is cut by a surface to be cut vertically, only one of the cells 76 is cut, but here, the cell 76 is shown on both sides in order to clarify the relationship with the thermostat 71.

  The cell 76 is a container having an open top and a round cross section. In the case of a rectangular cell, there is a problem that cleaning cannot be performed sufficiently or it takes time to perform sufficient cleaning. However, if it is a round cell, sufficient cleaning can be performed in a short time. The cell 76 may be made of a material usually used in this field. For example, the cell 76 is made of a material such as glass or various synthetic polymers (polyethylene, polypropylene, polystyrene, fluororesin (PTFE), etc.). In general, it is made of a transparent material. Of these, those made of polypropylene, polystyrene or other water-repellent materials are preferred. The reason why such a material is used is that cleaning by the cleaning unit 18 is easy, durable, and water-repellent.

  Further, the rotation of the motor 80 is controlled by the information processing unit 11 as a control unit so that the measuring cell 76 moves at a constant speed. It is difficult to always stop each cell 76 accurately at the position of the photometry unit 17, and even if it is attempted to stop, variation in the stop position is likely to occur. If the cells are rectangular, there is no problem even if there is some variation in the stop position, but if a round cell is adopted, if the stop position varies, the measurement data in the photometry unit 17 is likely to vary, Stable measurement is not possible. That is, since the intensity of the light beam that has passed through the cell 76 (hereinafter sometimes abbreviated as transmitted light) also depends on the thickness (optical path length) of the cell 76 containing the liquid to be measured, the cell is round. In this case, the optical path length is completely different between the end portion and the central portion of the cell 76, and the intensity of transmitted light in both is different. In addition, the intensity of the transmitted light differs between the vicinity of the focal point of the transmitted light generated by the lens effect of the cell 76 and the liquid (reagent + sample) held inside and the outside (ie, the central portion and the end portion). . For this reason, the transmitted light intensity varies due to variations in the stop position. In order to solve such a problem, an embodiment according to the present invention has been completed. As will be described in detail below, the intensity of transmitted light from the cell 76 is continuously measured while moving the cell 76 at a constant speed instead of stopping the cell 76 at the time of measurement, and the measured value is plotted continuously. Then, a process of specifying a peak point in a curve drawn from the plotted points is performed, and the variation is removed by setting the peak point as an actual measurement value (peak value) of the cell. In other words, if the cell 76 is moved at a constant speed, no matter where the peak point appears in the above curve, as long as the peak value of the peak point can be specified, the maximum amount of transmitted light in the cell can be determined. The output value can be detected. Therefore, since it can be considered that the maximum output value in the liquid held in each cell 76 is measured under a certain condition, variation can be reduced.

  In addition, once the specific cell 76 is moved to the reference position and then the rotation angle of the rotation shaft 72 is measured, it can be understood which cell 76 has passed the position where the photometry unit 17 is provided. . That is, in the information processing unit 11, the cell 76 or the sample (ID) held in the cell 76 or the sample collection source (subject ID) and the measurement data or the analysis result are associated with each other and stored in the storage device. it can.

  Next, the configuration of the photometry unit 17 will be described with reference to FIGS. FIG. 5A is a top view of the photometry unit 17, and FIG. 5B is a side view of the photometry unit 17. The photometry unit 17 includes a holding unit 173 a of the LED 201, a light guide unit 173 b of light emitted from the LED 201, a moving groove 173 d of the reaction tank 75, and a holding unit of a photodiode (PD) 202 corresponding to the transmitted light measurement unit. A main part 173 having 173c, a heat insulating body 171 for keeping a part of the main part 173 (such as a part of the holding part 173a of the LED 201), a PC board 174 for mounting the LED 201 of the main part 173, And a PC board 175 for mounting the PD 202 of the unit 173. The LED 201 side of the main part 173 and the PC board 174 are coupled by screws 174a to 174c and the like. Further, the PD 202 side of the main portion 173 and the PC board 175 are coupled by screws 175a to 175c and the like. In addition, although the heat insulating body 171 is not necessarily required, it is preferable to provide the heat insulating body 171 made of, for example, a heat insulating material such as polyurethane, because the LED 201 becomes more constant in temperature.

  As shown in FIG. 5A, the moving groove 173 d of the reaction tank 75 is provided with screw holes 176 a and 176 b for coupling to the constant temperature portion 71. Further, as shown in FIG. 5B, the reaction tank 75 moves through the moving groove 173d, and the light emitted from the LED 201 is irradiated to the side surface of the cell 76 through the light guide 173b. The Of course, the movement path 71f and the movement groove 173d are aligned so that the reaction tank 75 can move smoothly. Light transmitted through the cell 76 is detected by the PD 202.

  The photometry unit 17 has a large heat capacity and is thermally coupled to the constant temperature unit 71 to keep the temperature of the LED 201 constant. That is, the holding part 173a of the LED 201 is provided in a portion surrounded by the main part 173 and the heat retaining body 171 of the photometric part 17, and the photometric part 17 is thermally coupled to the constant temperature part 71. The holding portion 173a of the LED 201 is hardly affected by the outside world, and the temperature change of the LED 201 is suppressed to a minute. Therefore, stable light emission is performed. The main part 173 is made of, for example, aluminum. Moreover, the light guide part 173b is formed by cutting the main part 173 and making a hole together with the holding part 173a of the LED 201. When the main part 173 is made of aluminum and the light guide part 173b is formed by cutting and making a hole, the light emitted from the LED 201 is reflected by the inner wall and scattered only by leaving it hollow. The light intensity is made uniform at the outlet of the light guide 173b. Note that the cross-sectional shape of the light guide portion 173b is preferably a round shape, but is not limited thereto, and may be a polygonal shape.

  Next, details of the function of the photometry unit 17 will be described with reference to FIGS. 6 to 7C. As shown in FIG. 6, the LED 201 is connected to a constant current source 206 and is driven with a constant current in accordance with control by the information processing unit 11 that is a control unit. Thus, stable light emission is performed if the temperature is constant. However, since the LED 201 is close to a point light source, the intensity of the light emitted from the LED 201 (hereinafter sometimes abbreviated as emitted light) has a profile as indicated by a dotted line a in FIG. 7A. In FIG. 7A, the vertical axis represents the intensity of the emitted light, and the horizontal axis represents the distance (or position) from the center of the LED 201. Note that the LED 201 is disposed at the origin of the horizontal axis and emits light in the upward direction of the vertical axis. A dotted line a indicates a state in which the light intensity passes through the center of the LED 201 and is on the straight line in the irradiation direction (that is, in the front direction of the LED 201), and the light intensity decreases as the distance from the straight line increases. The transmitted light intensity obtained based on the electrical signal detected by the PD 202 while moving the round cell at a constant speed by using the round cell as a light holding unit using the LED itself having such a light intensity profile as a light source. If the values are continuously plotted, a transmitted light intensity curve as shown in FIG. 7B or FIG. 7C is obtained. 7B and 7C, the round cell 76 is rotated around the rotation axis 72 from the left to the right in the direction when the LED 201 is viewed in front, between the LED 201 and the PD 202 arranged (fixed) at a certain distance. Shows a transmitted light intensity curve obtained based on the electrical signal detected by the PD 202. 7B and 7C, the vertical axis represents the intensity of transmitted light, and the horizontal axis represents the measurement time of the intensity of transmitted light. In addition, the position of the origin on the horizontal axis represents the time when the center of the round cell 76 coincides with the straight line connecting the center of the LED 201 and the center of the PDP 202 for convenience. At this time, FIG. 7B shows a curve obtained when a round cell of a perfect circle is used, and if a curve with one apparent peak point is obtained in this way, the peak point by the method described later is obtained. Since detection is easy, there is no problem. However, FIG. 7C shows a curve obtained when a round cell having a distortion (for example, the center of the cell is shifted) is used, and a curve having a portion close to the flat is obtained. In such a case, the peak point is unclear or a plurality of peak points exist, so that there is a problem that an appropriate peak point cannot be detected with high accuracy (peak uncertainty). The problem of the uncertainty of the peak point has a great influence on the detection of the peak point in the peak detector described later. That is, for example, when a curve with apparently two peak points (or more) is input, it is unclear which of the peak points correctly reflects the characteristics of the round cell 76. Even if the first peak point can be correctly detected, the second and subsequent peaks may not be detected accurately. For example, when a curve as shown in FIG. 7C is obtained, even if the peak detection unit can detect the point d out of the two peak points c and d, either the point c or the point d is round. It is unknown whether the characteristics of the shaped cell 76 are reflected. In addition, when the point d is lower than the point c, the point c can be detected, but the point d cannot be detected in many cases. In such a case, the point c is detected, but if the point d is a point to be detected truly, an incorrect value is output. That is, it is unclear which peak can be detected to detect cell characteristics. In the measurement using the LED itself having a profile such as the dotted line a shown in FIG. 7A and a round cell, a curve as shown in FIG. 7C is often obtained. The peak point mentioned here means a point at a maximum value or a point at a minimum value in a differentiable curve, or a point in a curve having a point (a non-differentiable curve).

  Thus, when adopting a round cell from the viewpoint of ease of cleaning at the time of downsizing and further using LED 201 as a light source from the viewpoint of miniaturization and power saving, the inventors of the present application We faced a previously unknown problem of peak point uncertainty as mentioned. Increasing the accuracy of the shape of the round cell is difficult in terms of cost, and the inventors of the present application have made it non-obvious to remove it by modifying the light intensity profile of the LED 201 in order to solve this problem. Devised. Specifically, maintaining the light intensity profile of the emitted light as represented by the dotted line a in FIG. 7A emphasizes round cell problems such as round cell distortion and lens effects. As shown by the solid line b, the light intensity profile of the emitted light from the LED 201 is converted so as to have as flat a part as possible. Then, the problem of the round cell described above is almost converted into a shift of the detection time of the peak point if it is measured while moving at a constant speed (substantially one peak point), and the problem as described above. Has been eliminated, reproducibility is high, and stable and highly accurate measurement is possible.

  For this reason, in this embodiment, as shown by the solid line b in FIG. 7A, the flat portion to be irradiated to the light receiving surface of the cell 76 with the intensity of the light beam emitted from the LED 201 by the light guide portion 173b. Is converted to a profile like a step function. The light guide unit 173b has such a light intensity conversion function. When a light beam having a light intensity as shown by the solid line b in FIG. 7A is irradiated onto the portion that becomes the light receiving surface of the cell 76, a curve with one peak can be obtained as shown in FIG. 7B.

  Furthermore, the light guide unit 173b not only makes the density of the light rays on the light receiving surface of the cell 76 uniform, but also converts the light emitted from the LED 201 from direct light to scattered light, thereby holding the liquid (inside the cell 76). The influence of particles (for example, colloidal gold particles) contained in the sample and the reagent can be reduced. More specifically, for example, when light directly hits particles contained in a liquid (sample and reagent), the light is not emitted from the cell 76 as transmitted light. In other words, particles contained in the liquid (sample and reagent) block light. If such an effect is significant, the light intensity of the transmitted light becomes extremely weak, which causes a measurement error to increase. However, in the case of scattered light, the light travels so as to sew the particles contained in the liquid (sample and reagent), so that the light is transmitted through the cell 76, except when the light directly hits the particles. Become. For this reason, even if it is influenced by the particles contained in the liquid to be measured, the light intensity of the transmitted light does not become extremely weak, so that the measurement error is reduced.

  The light guide unit 173b scatters the light beam emitted from the LED 201 by the inner wall of the glossy cavity and performs the above-described conversion. However, the light guide unit 173b may be implemented by an optical fiber as well as the inner wall of the glossy cavity. An optical fiber has a structure in which a core with a high refractive index is provided at the center and a cladding with a low refractive index is provided around the core. In this way, the light beam travels while reflecting as little loss as possible on the inner wall. Should be adopted. However, if there is another element that can convert the light intensity of the dotted line a in FIG. 7A into the light intensity of the solid line b, it is also possible to use it. In addition, about the length of the light guide part 173b, it may be necessary to adjust according to the degree of flattening of light intensity. Further, the length varies depending on the configuration of the light guide 173b.

  In order to obtain more stable measurement data, a slit is provided at the outlet of the light guide 173b (on the opposite side of the LED 201 from the holding part 173a) to block the left and right ends of the light emitted from the LED 201. May be. It is sufficient to use a slit generally used in this field, and it moves with the cell 76 that moves at a constant speed even if it is fixed at the outlet of the light guide 173b (on the side opposite to the holding part 173a of the LED 201). It may be movable.

  The light beam having the light intensity as indicated by the solid line b in FIG. 7A and output from the outlet of the light guide 173b (on the side opposite to the holding portion 173a of the LED 201) is applied to the portion that becomes the light receiving surface of the cell 76. Irradiated. And the transmitted light of the cell 76 is measured in PD202 installed in the opposite side to the part used as the light-receiving surface of the cell 76. FIG. Since the PD 202 is an element that converts an optical signal into an electric signal corresponding to the light intensity, an electric signal having the same amplitude as the detected intensity is generated. The electric signal generated in this way is output to the signal processing unit 203.

  Although the type of signal processing may be changed depending on the sample contained in the cell 76, the signal processing unit 203 performs peak detection as an example here. That is, the signal processing unit 203 includes a peak detection unit 2031. When a curve such as that shown in FIG. 7B is input, the peak detection unit 2031 detects a peak point and holds a peak value. And output. Further, even when a curve having two (or more) peaks is input, a function of detecting and holding a higher peak point may be provided. The signal processing unit 203 may have a function of performing not only peak detection but also other signal processing, and the peak point value and the like may be processed together with these functions.

  The signal processing unit 203 is connected to an A (Analog) / D (Digital) conversion circuit 204, and the A / D conversion circuit 204 outputs a digital value such as a peak value to the information processing unit 11, for example. . The information processing unit 11 calculates the absorbance according to a predetermined calculation method from the peak value, for example. In addition, the peak value is measured for the cell 76 in a blank state in which an appropriate liquid (for example, purified water, ion-exchanged water, physiological saline, buffer solution, etc.) that does not contain insoluble matter is previously stored, and is actually measured by the same method. After measuring the peak value for the cell 76 in which the liquid containing the sample is held inside, the difference between the peak value for the cell 76 in the blank state and the peak value for the cell 76 holding the liquid containing the sample is calculated. If the absorbance is calculated from the difference, the absorbance of the actual sample + reagent can be obtained. For example, the information processing unit 11 performs such calculation. In addition, it is detected which cell 76 is measured by the position detection unit 205 such as a rotation angle detection unit, and the information processing unit 11 analyzes the measurement data (that is, peak value) or the analysis result such as absorbance, and the cell. 76 or a sample (ID) held in the cell 76 or a sample collection source (subject ID) is associated with each other and stored in a storage device (memory) (not shown).

  Note that the specific configuration of the peak detection unit 2031 is well known, and the calculation method for calculating the absorbance and the like from the peak value is also well known, and thus will not be described further.

  By adopting the configuration as described above, it is possible to employ a small and long-life light source called an LED, so that the analyzer can be miniaturized. Further, the variation in light intensity accompanying the temperature change, which is the most problematic when the LED 201 is employed in the analyzer, has been solved by the constant temperature. Furthermore, even when a container having a round cross section and not high accuracy is employed, high-accuracy measurement can be performed stably and without variation by constant speed movement of the container and uniform intensity of the output light of the LED 201. It becomes like this. Therefore, highly accurate analysis can be performed stably. In addition, since it is a round container, it is easy to clean and contamination problems are less likely to occur. Moreover, if a polypropylene container is employed, it can be reduced in size at a lower cost. Further, the amount of liquid to be used can be reduced in size.

  Although the embodiment of the present invention has been described above, the present invention is not limited to this. For example, the wavelength of the emitted light emitted from the LED 201 may be determined according to the type of the liquid to be measured, and in FIGS. 5A and 5B and FIG. 6, the LED 201, the light guide unit 173b, and the PD 202 are used. However, a configuration in which a plurality of sets, for example, two sets are provided is also possible. In this case, the wavelength of the light emitted from the LED 201 is made different. For example, when measuring the absorbance of a liquid to be measured (sample + reagent) for fecal occult blood analysis, it is usually 600 nm or more, preferably 620 nm or more, more preferably 630 nm or more, usually 800 nm or less, preferably 750 nm or less, more preferably 670 nm or less. In these wavelength regions, it is most preferable to employ a wavelength around 635 nm. Further, the wavelength region shorter than the above wavelength region is usually 500 nm or more, preferably 510 nm or more, more preferably 530 nm or more, usually less than 600 nm, 560 nm or less, 550 nm or less, and in these wavelength regions, 530 nm. Most preferably, a near wavelength is employed. The PD 202 is also changed according to the corresponding LED 201. As described above, by performing photometry according to so-called two-wavelength photometry, it is possible to remove the influence on the measurement due to turbidity or the like derived from the liquid (specimen).

  Further, the technique according to the present invention relates to measurement of transmitted light of a liquid to be measured, and any measurement method and principle for measuring transmitted light, and a sample and a reagent used therefor can be applied. In particular, a biological sample (for example, blood, plasma, serum, spinal fluid, saliva, urine, stool, etc.) is diluted or suspended with an appropriate liquid (for example, distilled water, ion-exchanged water, physiological saline, buffer, etc.). Obtained by mixing and reacting turbid sample as a sample, and mixing the sample with a reagent containing colloidal particles (for example, gold colloid particles, latex particles, etc.) bound to an antibody (or antigen) against the analyte in the sample. This is useful when measuring a measured liquid. In particular, stool is appropriately suspended in distilled water, ion-exchanged water, physiological saline, buffer solution, or the like, or a stool suspension solution or a filtrate obtained by filtering these is used as a sample, and the antibody against hemoglobin in the sample This is useful when performing so-called fecal occult blood analysis in which a liquid to be measured and the like obtained by mixing and reacting with a reagent containing colloidal gold particles bound to (or antigen) are measured.

  Further, the mechanical configuration described above can be variously modified in accordance with the gist described above. For example, it is not always necessary to divide the first and fourth heat insulation walls 71a and 71d and the second and third constant temperature walls 71b and 71c as in the constant temperature portion 71. Further, the photometry unit 17 may be formed in another shape because the LED 201 is kept at a constant temperature by being thermally coupled to the constant temperature unit 71 and the reaction tank 75 and the light guide unit 173b is provided. . Regarding the moving mechanism of the reaction tank 75, the mechanical configuration described above is merely an example, and other shapes may be adopted.

  Furthermore, in the embodiment described above, a circuit is assumed in which the peak detection unit 2031 detects and holds the peak point, so that only the peak value of the peak point is output to the information processing unit 11. It was. However, for example, after measuring the values of each point of the curve as shown in FIG. 7B and outputting all the values to the information processing unit 11, the information processing unit 11 specifies the peak point and its value. Also good.

It is a perspective view of the automatic analyzer which concerns on embodiment of this invention. It is a perspective view of the reaction part which concerns on embodiment of this invention. It is a perspective view of the thermostat which concerns on embodiment of this invention. It is sectional drawing of the reaction tank etc. which concern on embodiment of this invention. (A) is a top view of the photometry part which concerns on embodiment of this invention, (b) is a side view of a photometry part. It is a figure for demonstrating the function of the photometry part which concerns on embodiment of this invention. It is a figure for demonstrating the intensity | strength of the light beam output from LED. It is a figure showing the curve based on the intensity | strength of the light ray which permeate | transmitted the normal cell. It is a figure showing the curve based on the intensity | strength of the light ray which permeate | transmitted the cell in question.

Explanation of symbols

17 Photometry unit 71 Constant temperature unit 72 Rotating shaft 73 Reaction tank cover 74 Rotation connection unit 75 Reaction tank 76 Cell 173a LED holding unit 173b Light guide unit 173c PD holding unit 201 LED 202 PD 203 Signal processing unit 204 A / D 205 Position detection unit 206 Constant current source

Claims (10)

Holding the liquid to be measured, and the reaction vessel section comprises a liquid holding portion of the round, to and moving are thermostatic,
An LED light source thermally coupled to the reaction vessel;
A light guide for uniformizing the intensity of light emitted from the LED light source with respect to the light receiving surface of the liquid holding unit;
A light measuring unit that measures the intensity of the light beam that has passed through the liquid holding unit that has moved to the exit position of the light guiding unit during constant speed movement of the liquid holding unit ;
A processing unit that performs processing based on a signal from the light measurement unit;
Analytical apparatus having The analyzer according to claim 1, wherein the light guide unit scatters light rays from the LED light source. The analyzer according to claim 1, wherein the light guide unit is configured by a cylinder having a glossy inner wall. The analyzer according to claim 1, wherein the light guide unit is configured by an optical fiber. The analysis apparatus according to claim 1, wherein the processing unit performs a process of detecting a peak of the signal. The light guide part and the holding part of the LED light source are integrally formed as a measurement part,
The analysis device according to claim 1, wherein the measurement unit is connected to a thermostat that thermostats the reaction vessel.   The analyzer according to claim 1, wherein the liquid holding unit is made of polypropylene. The LED light source includes a plurality of LEDs having different wavelengths,
The analyzer according to claim 1, wherein the light guide unit and the light measurement unit are provided corresponding to each of the LEDs.   The analyzer according to claim 1, wherein the absorbance of the liquid to be measured is calculated by the processing unit.   The analyzer according to claim 1, wherein the processing unit performs processing for fecal occult blood analysis.

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