Analysis method and analysis apparatus

Abstract

An analysis device is provided which can exclude the influence of impurities during measurement and to acquire an accurate brightness value of a measurement target while avoiding costs from increasing and work processes from becoming complex. This analysis device 100, which is for analyzing samples, is provided with a light source 101, an imaging unit 103 which condenses transmitted light, receives the light intensity and acquires the brightness value, and a control unit 105. The analysis device 100 is provided with multiple reference samples 108 which differ in transmittance and color, and a storage unit 104 which stores the brightness values, and a control value of the light source 101. The control unit 105 irradiates the reference sample 108 with light at a set control value, and stores, in the storage unit 104, an acquired measured brightness value of the reference sample, and an adjustment control value of the light source 101 for adjusting to a set reference brightness value; from the brightness value of a sample to be measured, which was acquired by irradiating the sample 106 to be measured with light on the basis of the control value, the control unit 105 calculates an adjustment control value of the light source 101 on the basis of the relation between the adjustment control value of the light source 101 and the brightness value of the sample 106 to be measured, and uses the adjustment control value to irradiate light and, with the imaging unit 103, acquires the brightness value of the sample 106 to be measured.

Description

Technical Field

[0001] The present invention relates to an analysis method and an analysis apparatus that perform measurement while correcting the amount of light for each sample.

Background Art

[0002] An analysis apparatus that irradiates a sample with light and acquires a measurement value irradiates the sample with a certain amount of light from a light source, and acquires transmitted light, reflected light, or light emitted from the sample with a light receiving element. Then, the properties, concentration, shape, etc. of the sample are quantitatively measured from the amount of received light acquired by the light receiving element. When factors other than the sample, such as the sample containing impurities, affect the amount of received light, it causes a decrease in measurement accuracy.

[0003] For example, Patent Document 1 mentions a decrease in detection sensitivity due to changes over time in the components of the optical system and differences in instruments between devices.

[0004] Patent Document 1 addresses the problems of a decrease in detection sensitivity due to changes over time in the components of the optical system and differences in instruments between devices in a nucleic acid analysis apparatus that measures changes in fluorescence intensity over time. As a solution, an analysis apparatus is described that uses a reference sample with a certain concentration having a fluorescent dye and adjusts the current value of the light source so that the amount of fluorescent light emitted from the reference sample becomes a reference value.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] Incidentally, when impurities are mixed in the sample to be measured, the hue and concentration of the impurities affect the amount of received light, leading to a decrease in measurement accuracy. For example, in an analyzer for measuring the growth of bacteria using a biological sample solution such as blood, impurities such as hemoglobin and bilirubin in the blood components are factors, and the amount of received light decreases.

[0007] When imaging a biological sample solution with a camera, the light transmittance varies for each sample due to impurities, resulting in a difference in the obtained luminance. This reduces the analysis accuracy in image analysis.

[0008] The technique described in Patent Document 1 adjusts the light source so that the amount of received light becomes a reference value for a reference sample.

[0009] However, since the light source is not adjusted for each sample, the decrease in light transmittance occurring for each sample is not considered.

[0010] To solve these problems, in the conventional method, there is a need (method) to mix a reagent such as a fluorescent reagent or a staining agent that specifically reacts with the substance to be measured in advance into the sample to detect only the target substance, or to separate components by centrifugation or to prepare a bacterial solution from colonies formed by culturing bacteria in a bacterial examination to remove impurities from the sample in advance.

[0011] However, such methods of adding reagents or removing impurities have problems such as an increase in the cost for detection, a complication of the working process, and an increase in the measurement time.

[0012] Also, there may be cases where the influence of impurities cannot be completely removed.

[0013] In view of the above problems, an object of the present invention is to realize an analysis method and an analyzer capable of excluding the influence of impurities during measurement and obtaining an accurate luminance value of the measurement target while suppressing an increase in cost and a complication of the working process.

Means for Solving the Problems

[0014] In order to achieve the above object, the present invention is configured as follows.

[0015] In an analysis method of irradiating a sample with light and analyzing the sample using a light source that irradiates the sample with light, an imaging unit that condenses the transmitted light that has passed through the sample, receives the amount of condensed light, and obtains a luminance value, and a control unit that controls the light source and the imaging unit, light is irradiated from the light source using control values preset for two or more reference samples that differ in at least one of transmittance or color, the measured luminance value of the reference sample obtained by the imaging unit, and the adjustment control value of the light source at which the measured luminance value of the reference sample becomes a preset reference luminance value are stored in a storage unit, light is irradiated from the light source using the preset control value for the sample to be measured, and based on the relationship between the adjustment control value of the light source stored in the storage unit and the luminance value of the sample to be measured, the adjustment control value of the light source is calculated, and the light source is irradiated with light using the calculated adjustment control value to obtain the luminance value of the sample to be measured by the imaging unit.

[0016] In addition, an analyzer that irradiates a sample with light, condenses the transmitted light that has passed through the sample, receives the amount of condensed light, and acquires a luminance value, and a control unit that controls the light source and the imaging unit. In the analyzer that irradiates the sample with light and analyzes the sample, there are two or more reference samples in which at least one of the transmittance and color is different, and a storage unit that stores the luminance value and the control value of the light source. The control unit irradiates the reference sample with light using a control value preset for the reference sample, and stores in the storage unit the measured luminance value of the reference sample acquired by the imaging unit and the adjustment control value of the light source at which the measured luminance value of the reference sample becomes a preset reference luminance value. From the luminance value of the measurement target sample acquired by the imaging unit by irradiating the measurement target sample with light using the preset control value, based on the relationship between the adjustment control value of the light source stored in the storage unit and the luminance value of the measurement target sample, the adjustment control value of the light source is calculated, and the light source is irradiated with light using the calculated adjustment control value, and the imaging unit acquires the luminance value of the measurement target sample.

Advantages of the Invention

[0017] It is possible to realize an analysis method and an analyzer that can exclude the influence of impurities during measurement and obtain an accurate luminance value of the measurement object while suppressing an increase in cost and complication of the work process.

Brief Description of the Drawings

[0018]

Figure 1

Figure 2

Figure 3

Figure 4A

Figure 4B

Figure 5A

Figure 5B

Figure 6

Figure 7

Embodiments for Carrying Out the Invention

[0019] Hereinafter, embodiments of the present invention will be described with reference to FIG. 9. In each figure, common members are denoted by the same reference numerals.

Examples

[0020] (Example 1) Example 1 will describe an analysis method and an analysis apparatus that irradiate a sample with light to obtain a measurement value, and correct and measure the variation of impurities in a sample containing impurities on the received light amount. Impurities are components other than the substance to be measured, such as dye components and components that react with reagents. As dye components, for example, in a bacterial test using a blood culture sample, hemoglobin, which is a red dye contained in blood, and bilirubin, which is a yellow dye, can be mentioned.

[0021] FIG. 1 is a diagram showing the configuration of an analysis apparatus that irradiates a sample with light to obtain a measurement value in Example 1.

[0022] In FIG. 1, the analysis apparatus 100 is an analysis apparatus that irradiates a sample with light to obtain a measurement value. The analysis apparatus 100 includes a light source 101, an objective lens 102, a camera 103, a storage unit 104, and a control unit 105. The sample 106 is accommodated in the sample container 107 and held by the sample holding unit 110. The reference sample 108 is accommodated in the reference sample container 109 and stored in the storage unit 111.

[0023] Note that although the analysis device 100 contains one sample 106, which is the measurement target sample, in one sample container 107, it may contain one or more samples.

[0024] The reference sample 108 is two or more samples that differ in at least one of the light transmittance or color. One or more reference samples 108 may be contained in one reference sample container 109. Also, there may be one or more reference sample containers 109, and two or more reference samples 108 may be contained in a plurality of reference sample containers 109.

[0025] The light source 101 is a mechanism for irradiating the sample 106 with light. For example, it is a light-emitting diode or the like.

[0026] The objective lens 102 is a mechanism for condensing the light irradiated by the light source 101 onto the camera 103.

[0027] The camera 103 is a mechanism for receiving the light condensed by the objective lens 102 and measuring the amount of received light as a luminance value by an image sensor composed of a photodiode or the like.

[0028] The objective lens 102 and the camera 103 form an imaging unit, which is a mechanism for receiving the transmitted light that has passed through the sample 106, the reflected light reflected by the sample 106, or the light emitted by the fluorescent substance contained in the sample 106, and measuring the amount of received light, and may be a one-dimensional optical sensor.

[0029] The control unit 105 has a circuit board, software, etc., and controls the irradiation light amount of the light source 101, the exposure time of the camera 103, etc.

[0030] The storage unit 104 stores the luminance value acquired by the camera 103 and the control values for controlling the irradiation light amount of the light source and the exposure time of the camera, etc., by the control unit 105. In the example shown in FIG. 1, the storage unit 104 is provided inside the device, but it may be combined with an external system connected by a network, a universal serial bus (USB), or the like.

[0031] The holding unit 110 is a mechanism for installing and fixing the sample 106. Also, the holding unit 110 is a mechanism for installing and fixing the reference sample container 109. Fig. 1 shows a state in which the holding unit 110 installs and fixes the sample 106 accommodated in the sample container 107 and irradiates the sample 106 with light from the light source 101. However, the holding unit 110 can install and fix the reference sample 108 accommodated in the reference sample container 109 instead of the sample container 107 and irradiate the reference sample 108 with light from the light source 101.

[0032] The storage unit 111 is a mechanism for storing the reference sample container 109. The storage unit 111 may be inside the analyzer 100 or may be configured independently outside the analyzer 100.

[0033] Fig. 2 is a flowchart for obtaining a reference value for adjusting the irradiation light amount of the light source 101, which is executed by the control unit 105.

[0034] In Fig. 2, in step S201, the reference sample 108 is measured. For two or more reference samples 108, two values are respectively stored in the storage unit 104.

[0035] One is the luminance value (measured luminance value) obtained when irradiating the reference sample 108 with the reference light amount. The reference light amount is irradiated from the light source 101 to the reference sample 108 using a preset control value. Then, the luminance value (measured luminance value) obtained by the camera 103 is stored in the storage unit 104. Thereby, the relationship between the light transmittance or color and the obtained luminance can be obtained.

[0036] Therefore, the light transmittance or color of the sample 106 can be estimated from the measured luminance value when irradiating with the reference light amount.

[0037] Another is the amount of irradiation light that becomes a preset reference luminance value (true luminance value of the reference sample). The control value of the light source 101 is corrected to an adjusted control value so that the measured luminance value obtained by the camera 103 becomes the reference luminance value. Then, the adjusted control value of the light source 101 is stored in the storage unit 104. Thereby, it is possible to obtain the control value of the light source 101 for correcting the transmittance or color difference of light that is different for each sample 106 and obtaining the reference luminance value.

[0038] In step S202, a relational expression F between the control value of the light source 101 and the luminance value is obtained. From the values stored in step S201, a relational expression F of the adjusted control value for obtaining the reference luminance value is created with respect to the luminance value measured with the preset control value of the light source 101. As a result, since the adjusted control value for obtaining the reference luminance for each sample can be obtained from the luminance value measured with the preset control value of the light source 101 (the adjusted control value of the light source 101 can be calculated from the relational expression F), the adjustment time of the light source 101 can be shortened.

[0039] The relational expression F is an approximate relational expression of a linear function, an n-th order function (n is an integer of 2 or more), a logarithmic curve, etc. by the least squares method or the like for the numerical value pair of "the luminance value measured with the preset control value of the light source 101" and "the control value (adjusted control value) of the light source 101 that becomes the reference luminance value" measured and stored for two or more reference samples in step S201.

[0040] FIG. 3 is a flowchart for adjusting the irradiation light amount of the light source 101 and measuring the measurement target sample, which is executed by the control unit 105.

[0041] In FIG. 3, in step S301, the sample 106, which is the measurement target sample, is measured, and the transmittance or color of the light of the impurities contained in the sample 106 is estimated. Light is irradiated from the light source 101 to the sample 106 using a preset control value. Then, the measured luminance value obtained by the camera 103 is applied to the relational expression F obtained in step S202, and the control value of the light source 101 for each sample 106 is stored in the storage unit 104.

[0042] In step S302, the transmittance of light or the color difference of impurities contained in the sample 106 is corrected, and the measurement of the sample 106 is performed. Using the control value of the light source 101 stored in step S301, the measurement of the sample 106 is performed.

[0043] Figures 4A and 4B are diagrams for explaining the relationship of the control value of the light source 101 with respect to the reference sample.

[0044] In Figure 4A, the reference sample 401 shows examples of a plurality of transmittance reference samples 108. The transmittance reference sample 108 is two or more samples in which at least one of the light transmittance or color is different, and shows the cases where the samples have transmittances of 100%, 80%, and 60%. When the control value of the light source 101 stored in step S201 and the luminance correspond to the correspondence shown in the relationship 402 between the luminance and the light amount with respect to the reference sample, the relational expression F in step S202 becomes the expression 403 shown in Figure 4B. In Figure 4B, the vertical axis represents the control value of the light source 101 as the reference base value, and the horizontal axis represents the luminance value measured with the preset control value of the light source 101.

[0045] Figures 5A and 5B show the relationship of the control value of the light source with respect to the sample.

[0046] In Figure 5A, the sample 501 is an example of the sample 106 in which impurities are mixed. The transmittance of the light of the impurities is unknown. Therefore, the transmittance of the light of the impurities is estimated from the luminance value measured with the preset control value of the light source 101 in step S302. The expression 502 in Figure 5B shows a method for determining the value for controlling the light source 101 at the time of measuring the sample 106 from the relational expression F obtained in step S202.

[0047] As described above, according to the first embodiment, in the analysis method and the analysis apparatus that irradiate light on the sample and acquire the measurement value, for the sample 106 containing impurities, the control value of the light source 101 is corrected so that the luminance value becomes constant. As a result, the variation in the received light amount caused by the impurities is suppressed, the accuracy of the image analysis is improved, and the effect that the measurement accuracy can be improved is obtained.

[0048] In addition, by using the analysis method and the analysis apparatus of the first embodiment, the control value of the light source for correcting the amount of irradiation light of each sample can be determined from the result of measurement performed with the preset control value of the light source. Therefore, it is not necessary to search for an appropriate control value of the light source, and the correction time of the light source for each sample can be shortened.

[0049] In addition, according to the first embodiment, the step of reacting a reagent with the sample or removing impurities by the user becomes unnecessary, and the time required for measurement can be shortened. Then, the reagent becomes unnecessary, leading to cost reduction.

[0050] That is, according to the first embodiment, it is possible to realize an analysis method and an analysis apparatus capable of excluding the influence of impurities during measurement and obtaining an accurate luminance value of the measurement object while suppressing an increase in cost and complication of the work process.

[0051] (Second Embodiment) Next, the second embodiment will be described.

[0052] In the second embodiment, in an analysis method and an analysis apparatus that irradiate a sample with light and acquire a measurement value, an analysis method and an analysis apparatus that correct and measure the variation in the amount of received light caused by impurities contained in the sample and the decrease in detection sensitivity due to the deterioration of components over time and the influence of instrumental differences between apparatuses on the amount of received light will be described.

[0053] In the second embodiment, the configuration of the analysis apparatus that irradiates a sample with light and acquires a measurement value is the same as that of the first embodiment (the content described with reference to FIG. 1).

[0054] In the first embodiment, a reference sample 108 whose light transmittance or color is known in advance is irradiated with a reference light amount, and based on the acquired luminance value and the irradiation light amount of the light source 101 for obtaining a reference luminance value, the control value of the light source 101 when measuring the sample 106 is determined. Thereby, an analysis method and an analysis apparatus for correcting the variation in the amount of received light caused by impurities have been described.

[0055] In Example 2, in Example 1, when irradiating the reference sample 108 with the reference light amount, the obtained luminance value and the irradiation light amount of the light source 101 for obtaining the reference luminance value are repeatedly measured at regular intervals, thereby correcting the variation in the received light amount caused by impurities, the instrumental error of the apparatus, and the deterioration of the components of the apparatus over time.

[0056] FIG. 6 is a measurement flowchart of the reference sample in Example 2 executed by the control unit 105.

[0057] In FIG. 6, in step S601, it is determined whether or not to measure the reference sample 108. It is determined whether or not a period T, which is a certain period, has elapsed since the previous reference sample measurement (the measurement for obtaining the relational expression F described in Example 1). If the period T has not elapsed since the previous reference sample measurement, the process ends. If the period T has not elapsed or if the measurement has never been performed, the process proceeds to step S602, the reference sample 108 is measured, and steps S201 and S202 shown in FIG. 2 are performed.

[0058] FIG. 7 is a measurement flowchart of the measurement target sample 106 in Example 2 executed by the control unit 105.

[0059] In FIG. 7, in step S701, the sample 106 is measured, and step S301 shown in FIG. 3 is performed. Next, in step S702, based on the reference sample 108 measured in step S602 shown in FIG. 6, step S302 shown in FIG. 3 is performed. Next, in step S703, it is determined whether or not the sample 106 has completed the measurement an arbitrary number of times (C times).

[0060] Each sample 106 repeatedly performs the process of step S702 at regular intervals and measures with the control value of the same light source 101. The sample that has completed the measurement an arbitrary number of times (C times) ends the measurement. At this time, while performing step S702 for one sample 106 and repeatedly measuring, the process of step S701 or step S702 may be performed for another sample 106.

[0061] Here, in step S703, an explanation will be given about the necessity to repeatedly measure the sample 106 any number of times.

[0062] When the detection unit that measures the received light amount is a two-dimensional sensor such as the camera 103 and the measurement aims to capture the shape of the object depicted in the image, the control value of the light source is corrected using, as the reference luminance, the average value of the luminance detected by a plurality of elements, etc. By measuring the sample 106 once using the said control value, an image in which the difference in the average luminance of the images generated between the samples 106 (contrast difference) is corrected can be obtained.

[0063] Thereby, in binarization processing, etc. when extracting an object in image analysis, it becomes easy to set the luminance threshold value to be constant.

[0064] On the other hand, when the detection unit that measures the received light amount is a one-dimensional sensor such as a diode and the measurement aims to capture the change over time of the sample 106, the control value of the light source 101 is corrected so that the same luminance is obtained for the sample 106. By measuring the sample 106 two or more times using the said control value, the difference in luminance generated between the samples 106 can be corrected, and the change in luminance over time can be captured.

[0065] Also, when the detection unit that measures the received light amount is a two-dimensional sensor such as the camera 103 and the measurement aims to capture the change over time of the object (measurement target sample) depicted in the image, the control value of the light source 101 is corrected using, as the reference luminance, the average value of the luminance detected by a plurality of elements, etc. By measuring the sample two or more times using the said control value, the change in luminance over time with respect to the image in which the difference in the average luminance of the images generated between the samples 106 (contrast difference) is corrected can be obtained.

[0066] That is, the control unit 105 causes the adjustment control value of the light source 101 to be stored in the storage unit 104 for each measurement target sample 106, and in the measurement of the change over time of the measurement target sample 106, the light source 101 is corrected using the adjustment control value, and measurement can be performed.

[0067] For the reasons described above, in step S703, the sample 106 is measured repeatedly any number of times. Note that the arbitrary number of times may be two or more.

[0068] As described above, in the second embodiment, the same effects as those in the first embodiment can be obtained. In addition, in the analysis method and the analysis apparatus for irradiating the sample 106 with light and acquiring the measurement value, the control value of the light source 101 is corrected based on the measurement value of the reference sample 108. Further, the reference sample 108 is repeatedly measured at regular intervals. Thereby, even when the amount of received light fluctuates due to impurities contained in the sample 106, or even when the amount of irradiated light of the light source 101 decreases due to instrumental errors of the analyzer 100 or deterioration of components over time, the measurement accuracy can be improved by changing the value for controlling the light source 101 during sample measurement. In addition, the service life of each component can be extended.

[0069] Note that the above-described embodiment is an exemplification for explaining the present invention, and is not intended to limit the scope of the present invention only to the embodiment.

Explanation of Reference Numerals

[0070] 100... Analyzer, 101... Light source, 102... Objective lens, 103... Camera, 104... Storage unit, 105... Control unit, 106... Sample, 107... Sample container, 108... Reference sample, 109... Reference sample container, 110... Holding unit, 111... Storage unit

Claims

1. In an analysis method for irradiating a sample with light and analyzing the sample, using a light source that irradiates the sample with light, an imaging unit that condenses the transmitted light that has passed through the sample, receives the amount of condensed light, and acquires a luminance value, and a control unit that controls the light source and the imaging unit, irradiate the sample with light from the light source using control values preset for two or more reference samples having at least one of transmittance or color different, store in a storage unit a relational expression between the measured luminance values of the two or more reference samples acquired by the imaging unit and two or more adjustment control values of the light source for the measured luminance values of the two or more reference samples to become preset reference luminance values, irradiate the sample to be measured with light from the light source using the preset control values, calculate the adjustment control value of the light source based on the relational expression stored in the storage unit from the luminance value of the sample to be measured acquired by the imaging unit, characterized in that light is irradiated from the light source using the calculated adjustment control value, and the imaging unit acquires the luminance value of the sample to be measured.

2. In the analysis method according to Claim 1, store the adjustment control value of the light source in the storage unit for each sample to be measured, and correct the light source using the adjustment control value in the measurement of the change over time of the sample to be measured, and perform measurement.

3. In the analysis method according to Claim 1, when a certain period has elapsed since the previous measurement of the reference sample, perform measurement of the reference sample, characterized in that a relational expression between the measured luminance values of the two or more reference samples and two or more adjustment control values of the light source for the measured luminance values of the two or more reference samples to become preset reference luminance values is newly obtained and stored in the storage unit.

4. An analysis apparatus for irradiating a sample with light and analyzing the sample, comprising a light source that irradiates the sample with light, an imaging unit that condenses the transmitted light that has passed through the sample, receives the amount of condensed light, and acquires a luminance value, and a control unit that controls the light source and the imaging unit, two or more reference samples having at least one of transmittance or color different, a storage unit that stores the luminance value and the control value of the light source, comprising, the control unit is, Using the control values preset for the reference sample, irradiate light from the light source, and store in the storage unit a relational expression between the measured luminance values of the two or more reference samples acquired by the imaging unit and two or more adjustment control values of the light source for the measured luminance values of the two or more reference samples to become preset reference luminance values. An analyzer, comprising: irradiating light from the light source using the preset control values for the sample to be measured, calculating the adjustment control value of the light source based on the relational expression stored in the storage unit from the luminance value of the sample to be measured acquired by the imaging unit, irradiating light from the light source using the calculated adjustment control value, and acquiring the luminance value of the sample to be measured by the imaging unit. **Claim 5** In the analyzer according to claim 4, the control unit stores the adjustment control value of the light source in the storage unit for each sample to be measured, corrects the light source using the adjustment control value in the measurement of the change over time of the sample to be measured, and performs measurement. **Claim 6** In the analyzer according to claim 4, the control unit when a certain period has elapsed since the previous measurement of the reference sample, performs the measurement of the reference sample, newly obtains a relational expression between the measured luminance values of the two or more reference samples and two or more adjustment control values of the light source for the measured luminance values of the two or more reference samples to become preset reference luminance values, and stores the relational expression in the storage unit.

Images