JP2008058155A - Medical photometer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a medical photometer which enables simultaneous multiwavelength measurement that has long been a problem, comprising a feature to obtain a dark signal of a light receiving element and a sensitivity adjustment signal which suppresses the effect of intensity change of a light source and a feature to enable the selection of not a prescribed wavelength but an arbitrary wavelength, by suppressing change of a reaction liquid due to applied light by reducing energy of the applied light as an advantage of a monochromator-type photometer, and by performing signal processing by dividing the light into two by a half mirror and producing a reference signal. <P>SOLUTION: This medical photometer comprises: a light source for generating white light which penetrates a sample; a spectral means for separating the white light which penetrates the sample into monochromatic light; a light receiving means for receiving the monochromatic light separated by the spectral means; and a wavelength selection means for changing a wavelength of the monochromatic light. A rotating slit with a reflector is used as the wavelength selection means. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a medical photometer, and more particularly to a medical photometer used for multi-wavelength simultaneous spectroscopic measurement when directly analyzing a specimen obtained by reacting serum and a reagent.

  The method of performing a wet reaction analysis on a sample obtained by reacting serum with a reagent can accurately define analysis conditions such as the temperature of the analytical reaction and the temperature of the reactant. For this reason, the medical photometer used in this wet analysis method is excellent in reproducibility and quantitative accuracy, and is widely used as an indispensable device for diagnosing and early detection of diseases in hospitals, clinical laboratory centers, health centers and the like.

  On the other hand, there is an automatic analyzer as an apparatus that can automate a series of pretreatments such as sample and reagent dispensing, stirring, and reaction time management to perform the above-described analysis. In contrast to this automatic analyzer, a medical photometer is indispensable as a device for manually performing the above-mentioned pre-processing as a backup machine for automatic analyzers, measuring small samples, and measuring special items. It is a device.

  The medical photometer is roughly composed of a pump, a photometer, and a signal processing unit called a sipper used for sucking a reaction solution into a photometer flow cell.

  In particular, the photometer splits the light emitted from the light source with a diffraction grating or interference filter, and then irradiates the monochromatic light only in the target wavelength range to the reaction liquid in the flow cell (monochromator type), It is classified into a white light illumination method (polychromator type) in which white light emitted from a light source is irradiated to the reaction solution in the flow cell.

  As a typical medical photometer, a monochromator type dedicated device is often seen.

  In this monochromator type medical photometer, first, light emitted from a light source passes through a lens, a window, and a slit and then enters a concave diffraction grating.

  The light is split here, and an image of the entrance slit is formed on the exit slit arranged on the Roland circle. The monochromatic light emitted from the exit slit passes through the flow cell and enters a detector such as a silicon diode.

  To select the wavelength that passes through the flow cell, the rotational angle of the concave diffraction grating is set, and the eccentric cam is motor controlled. This makes it possible to select a wavelength necessary for the biochemical examination such as the diagnosis of the disease described above.

  As described above, a minute current output from a detector such as a silicon diode is amplified by an amplifier, and the signal is A / D converted and input to a microcomputer. The computer also performs absorbance conversion and concentration conversion of the input signal.

  In many cases, in the A / D conversion, the absorbance is measured by the difference from the reference by logarithmic conversion.

  Even in this case, in order to prevent the drift of the amplifier, the change in sensitivity of the detector, and the change in brightness of the light source from adversely affecting the measured value, the optical chopper is rotated to obtain a dark signal and a sensitivity adjustment signal. Then, the time-divided optical signal is processed, or the light is bisected by a half mirror to create a reference side signal, and signal processing is performed.

  For this reason, it is inevitable that the photometer itself will be large and control and adjustment will be complicated, but continuous spectral characteristics can be obtained even if it takes time to rotate the diffraction grating with a wavelength cam or micrometer. Since the energy of the light applied to the reaction solution is small, there is an advantage that the reaction solution does not change due to the influence of the applied light.

  However, the above methods such as time-division optical signal processing can obtain a dark signal and a sensitivity adjustment signal. However, since the sample is irradiated with light split into monochromatic light, measurement is performed by simultaneously irradiating the same sample with two wavelengths. I can't do it.

  In addition, multi-wavelength measurement can be performed by controlling the rotational angle setting eccentric cam motor of the concave diffraction grating at high speed. However, since processing takes time, accurate results are obtained when monitoring the reaction process of the measurement sample. I can't.

  In contrast, in the case of a polychromator type spectrophotometer using an array type light receiving element, light emitted from the light source passes through a lens or window, passes through one of a flow cell or a dedicated reaction vessel, and passes through a slit. After that, it enters the concave diffraction grating.

  The light is split here, and an image is formed for each wavelength on a plurality of silicon detectors arranged on a Roland circle.

  Since the detectors are located at a plurality of wavelengths necessary for biochemical examinations such as the above-mentioned disease diagnosis, if a detector is selected, the wavelength is selected, and wavelength photometry can be performed almost simultaneously.

  Multi-wavelength photometry is effective in reducing errors due to turbidity of reaction solutions and bubbles in the flow cell when performing spectroscopic measurement using a flow cell for clinical use.

  However, in the case of this polychromator type spectrophotometer, unlike the monochromator type, the energy of the light irradiating the reaction liquid is large, and there is a drawback that the reaction liquid can change due to the influence of the irradiating light. It becomes difficult to obtain a sensitivity adjustment signal.

  Patent Document 1 discloses a spectrophotometer having both functions of a double monochrome-double beam spectrophotometer and a single monochrome dual wavelength spectrophotometer by switching mirrors, shutters, and the like.

JP 7-318484 A

  As described above, in order to enable simultaneous multi-wavelength photometry, two monochromators are provided, a double beam spectrophotometer that performs spectroscopy at two wavelengths, or a polychromator type that separates and separates white light into multiple colors. Although it is conceivable to use a spectrophotometer, in this case, in order to perform multi-wavelength photometry at the same time, a light receiving element, a detection amplifier, and an A / D converter for the wavelength are necessary, and it is actually costly.

  Moreover, there existed a fault which the reaction liquid influence and sensitivity adjustment which are the advantages of the monochromator type photometer mentioned above become difficult.

  On the other hand, multi-wavelength photometry in a monochromator type photometer has a method of controlling the rotational angle setting eccentric cam motor of the concave diffraction grating at a high speed. However, since processing takes time, it is accurate when monitoring the reaction process of the measurement sample. The result is not obtained.

  The present invention is an advantage of the monochromator type photometer, which reduces the energy of the light to be irradiated, suppresses the change of the reaction solution due to the influence of the light to be irradiated, bisects the light by a half mirror, creates a reference side signal, and performs signal processing. Simultaneous multi-wavelength photometry, which has been a problem, has the advantage of obtaining a dark signal of the light receiving element and a sensitivity adjustment signal that suppresses the influence of changes in the luminance of the light source, and the ability to select an arbitrary wavelength instead of the specified wavelength. It is an object of the present invention to provide a medical photometer that makes it possible.

  The present invention includes a light source that generates white light that passes through a sample, a spectroscopic unit that splits white light that has passed through the sample into monochromatic light, a light receiving unit that receives monochromatic light that has been split by the spectroscopic unit, and Wavelength selection means for changing the wavelength of monochromatic light is provided, and a rotating slit with a reflecting mirror is used as the wavelength selection means.

More specifically, the present invention is configured as follows.
(1). Select a light source that emits white light to irradiate the spectroscopic means, a spectroscopic means that splits the white light into monochromatic light for each wavelength, and a wavelength that allows the monochromatic light dispersed by the spectroscopic means to pass through the sample. A wavelength selection unit that divides the monochromatic light into two, generates a reference side signal, and performs a differential signal processing, and passes one of the same wavelengths divided by the light division unit through the sample to the light receiving element. In a medical photometer comprising a light receiving means for irradiating one of the other light receivers and an analyzing means for analyzing a sample component according to the output from the light receiving means, the absorbance of the sample is measured for each wavelength selected by the wavelength selecting means. Calculate and analyze sample components.
(2). Preferably, in (1), a flow cell is provided for allowing the sample to flow therein, and white light from the light source passes through the sample flowing in the flow cell and is applied to the spectroscopic means.
(3). Preferably, in the above (1) and (2), the monochromatic light is divided into two, a reference side signal is created, and differential signal processing is performed.

  Preferably, in the above (1), (2) and (3), a wavelength selection means for changing the wavelength of the monochromatic light is used as the wavelength selection means, and a plurality of wavelengths are continuously provided to one sample and the light receiving means. Irradiate and perform multi-wavelength photometry.

  According to the present invention, while taking advantage of the monochromator type photometer, it is possible to perform multi-wavelength measurement with a simple configuration without requiring a light receiving element for a wavelength, a detection amplifier, and an A / D converter, and a stable result. Can be obtained accurately.

  That is, the structure for performing multi-wavelength measurement, the number of light receiving elements and signal processing circuits can be reduced, and the production cost can be reduced.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a schematic configuration diagram of an embodiment of a medical photometer according to the present invention.

  In FIG. 1, the photometer unit of the medical photometer according to the embodiment of the present invention is configured by a monochromator method.

  The light source 1 is held by the light source holding means 2 so that the heat generated from the light source 1 is not conducted to other members.

  The white light (multi-wavelength light) generated from the light source 1 passes through the slit 3 and enters the concave diffraction grating 4 included in the spectroscopic means.

  The light incident on the concave diffraction grating 4 is split here, and the monochromatic light thus split is selected as monochromatic light having an arbitrary wavelength by the concave diffraction grating driving mechanism 5, and the rotating slit 6 with a reflector included in the wavelength selection means. Is irradiated.

  Twelve slits are arranged on the circumference of the rotary slit 6, and the selection of these slits is rotationally controlled by the rotary slit drive mechanism 7 and the slit position sensor 8, and allows the passage of monochromatic light of 12 types of wavelengths.

  Although the interval between the twelve slits is constant, the maximum long wavelength monochromatic light 9 of the wavelength selected by the concave diffraction grating driving mechanism 5 passes through the rotary slit 6 as it is, and the 11 wavelength monochromatic light below the long wavelength monochromatic light 9 is After passing through the rotary slit 6, it is reflected by the mirror 10.

  The 12-wavelength monochromatic light that has passed through the rotating slit 6 is limited to a wavelength width of 5 nm, passes through the light-shielding mask 11 so that other wavelengths are not mixed, and each of the 12 wavelengths is condensed on the half mirror 120.

  The monochromatic light that has passed through the half mirror 120 passes through the flow cell 13 and is irradiated to the sample side detector 14 included in the light receiving means, and the monochromatic light that has reflected off the half mirror 120 is irradiated to the reference side detector 15 included in the light receiving means. Is done.

  On the other hand, the reaction liquid 16 in which the operator determines the items to be analyzed in advance and reacts the target reagent with the patient serum to complete the pretreatment, the flow cell is fed from the reaction liquid suction nozzle 17 by the tube 18 and the sipper pump 19. A specified amount is sucked into 13.

  Then, the reaction liquid whose measurement has been completed is discharged from the flow cell 13 by the next reaction liquid, and the reaction liquid 16 is successively sent to the flow cell 13 by this repeated operation, and is sequentially discharged to the waste liquid bottle 20.

  Signals such as a sipper control signal 21 for controlling the rotation of the sipper pump 19, a flow cell temperature control signal 22 for controlling the temperature of the flow cell 13, a concave diffraction grating drive signal 23, and a rotary slit drive signal 24 are transmitted and received by the microcomputer 27. Be controlled.

  The measurement result is obtained by calculating a difference between the photocurrent outputs of the sample-side detector 14 and the reference-side detector 15 by the logarithmic converter 25, and the light-receiving element signal (logarithmic value) calculated by the difference is sent to the microcomputer 27.

  The analysis result processed by the microcomputer 27 is printed by, for example, a print output means 28 such as a thermal printer having a high-speed paper feed mechanism and simultaneously displayed on a display means 29 such as a liquid crystal module.

  In accordance with the analysis items described above, measurement conditions such as the wavelength and the suction amount of the reaction liquid are set in advance by the parameter input means 30 by the operator. The temperature of the flow cell 13 is controlled by the microcomputer 27.

  Further, the flow cell 13 has a structure in which bubbles are easily removed, and the joint portion connecting the flow cell 13 and the flow path (tube 18) is also devised obliquely so that the bubbles are removed.

  FIG. 2 is a detailed view of the rotary slit 6 in the medical photometer shown in FIG.

  12 slits having holes of equal size on the circumference of the rotary slit 6 are arranged at an angle of 30 °, and the longer wavelength side is based on the slit position detection plate 31 included in the detection means for detecting the slit position. 12 different wavelengths can be selected by changing the slit position to the center of the circle from the short wavelength side to making a hole.

  The 12 standard wavelengths are 800, 750, 700, 660, 600, 570, 546, 505, 480, 450, 405, and 340 nm used in biochemical analysis, and all 11 slits except the longest wavelength are used. , The monochromatic light reflected by the mirror 10 passes through the half mirror 120, and all 12 wavelengths including the longest wavelength are irradiated to the detector.

  FIG. 3 is a schematic operation flowchart for signal processing during sample measurement in the present invention.

  The light receiving element signal is converted into a logarithmic value using a logarithmic amplifier 25.

  In step 100 of FIG. 3, analysis conditions such as measurement time and measurement wavelength are set.

  Next, in step 101, it is selected whether to perform multi-wavelength measurement or single-wavelength measurement.

  If single wavelength measurement is selected, the wavelength selected in step 100 is set to the longest wavelength slit position by the concave diffraction grating driving mechanism 5 in step 102.

  On the other hand, when multi-wavelength measurement is selected, the longest wavelength slit position is set to 800 nm by the concave diffraction grating driving mechanism 5 in step 103 so that the standard 12 wavelengths are obtained.

  Here, when the measurement is performed by changing the above-described 12 wavelengths in the multi-wavelength measurement, the wavelength is left as it is, and the concave diffraction grating driving mechanism 5 selects an arbitrary wavelength at the longest wavelength slit position.

  Next, in step 104, the photometric values of all 12 slits are stored (not shown) regardless of the selection of single wavelength or multiple wavelengths in step 101 while rotating the rotary slit.

  Here, the rotating slit operates at a pitch of 30 °, and repeats the operation of finishing the measurement of one slit and feeding the next slit 30 °, and at a speed of 500 rpm to 3000 rpm according to the measurement time set in step 100. The measurement time is monitored in step 105. If the measurement time is not reached, the measurement in step 104 is repeated.

  In this way, the same wavelength is not repeatedly measured, but a plurality of wavelengths are repeatedly measured at a high speed to suppress the influence of the time difference of the sub wavelength with respect to the main wavelength as much as possible, and the same effect as the simultaneous multi-wavelength measurement can be obtained.

  If the measurement time is reached in step 105, the process proceeds to step 106, and the absorbance calculation for all 12 wavelengths is performed from the integrated value for the number of times described above.

  In step 100, the designated wavelength is selected from the absorbance data of the 12 wavelengths, and a calibration curve is calculated or, if a calibration curve has already been created, a concentration calculation using the calibration curve is performed.

  In step 107, the measured absorbance and concentration of the sample are displayed on the display means 29 and printed out by the print output means 28.

As described above, according to one embodiment of the present invention, the energy of the irradiation light, which is an advantage of the monochromator type photometer, is reduced, the change of the reaction solution is suppressed by the influence of the irradiation light, and the light is emitted by the half mirror. Features of obtaining a sensitivity adjustment signal that suppresses the dark signal of the light receiving element and the luminance change of the light source by creating a reference side signal and performing signal processing, and the ability to select any wavelength instead of the specified wavelength In addition, multi-wavelength photometry, which has been difficult in the past, can be performed, and the reliability of the medical spectrophotometer can be improved.

  Unlike polychromator-type photometers, it has a simple configuration without the need for light-receiving elements, detection amplifiers, and A / D converters for wavelengths, and can reduce production costs compared to polychromator-type photometers. I can plan.

  In the above-described example, the reference signal side detector using the half mirror is used to obtain the dark signal of the light receiving element and the sensitivity adjustment signal that suppresses the influence of the luminance change of the light source. The present invention can also be applied to other monochromator type photometers that do not use an instrument.

It is a schematic block diagram of one Embodiment of the medical photometer which concerns on this invention. FIG. 2 is a detailed view of a rotary slit shown in FIG. It is a general | schematic operation | movement flowchart about the signal processing at the time of the sample measurement in this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Light source, 2 ... Light source holding means, 3 ... Slit, 4 ... Concave diffraction grating, 5 ... Concave diffraction grating drive mechanism, 6 ... Rotation slit, 7 ... Rotation slit drive mechanism, 8 ... Slit position sensor, 9 ... Long wavelength Monochromatic light, 10 ... mirror, 11 ... mask, 120 ... half mirror, 13 ... flow cell, 14 ... sample side detector, 15 ... reference side detector, 16 ... reaction liquid, 17 ... reaction liquid suction nozzle, 18 ... tube, DESCRIPTION OF SYMBOLS 19 ... Sipper pump, 20 ... Waste liquid bottle, 21 ... Sipper control signal, 22 ... Flow cell temperature control signal, 23 ... Concave diffraction grating drive signal, 24 ... Rotary slit drive signal, 25 ... Logarithmic converter, 26 ... Light receiving element signal ( Logarithmic value), 27 ... microcomputer, 28 ... print output means, 29 ... display means, 30 ... parameter input means, 31 ... slit position detection plate.

Claims (4)

A light source that generates white light that passes through the sample;
Spectroscopic means for splitting white light transmitted through the sample into monochromatic light,
A light receiving means for receiving monochromatic light separated by the spectroscopic means;
A wavelength selection means for changing the wavelength of the monochromatic light;
A spectrophotometer using a rotating slit with a reflecting mirror as the wavelength selecting means. The spectrophotometer according to claim 1,
A spectrophotometer characterized in that a plurality of equal-sized slits are arranged at a predetermined angle on the circumference of the rotating slit so that a plurality of wavelengths can be selected. The spectrophotometer according to claim 2, wherein
The spectrophotometer characterized in that the predetermined angle is 30 ° and the number of slits is 12. In the spectrophotometer in any one of Claims 1-3,
A spectrophotometer comprising detecting means for detecting the position of the rotary slit.

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