Dialysis waste fluid component measuring device and method

Abstract

To provide a device and a method for component measurement for dialysis drainage capable of accurately measuring concentration of a component to be measured in dialysis drainage.SOLUTION: A component to be measured absorbs light of a first wavelength and emits fluorescent light of a second wavelength, and dialysis drainage includes a measurement inhibition component that absorbs the light of the first wavelength, and emits fluorescent light of a third wavelength. A device 1 for component measurement for dialysis drainage includes: a light source 2 for irradiating dialysis drainage with light of a first wavelength; an absorbance measurement unit 3 for obtaining absorbance from the light intensity of the transmitted light transmitted through the dialysis drainage; a first fluorescent light measurement unit 4 for measuring the light intensity of the fluorescent light of the second wavelength; a second fluorescent light measurement unit 6 for measuring the light intensity of the fluorescent light of the third wavelength; a ratio calculation unit 51 for calculating a ratio of the concentration of the component to be measured to the concentration of the measurement inhibition component on the basis of the results of the measurement by the two fluorescent light measurement units 4 and 6; and a component-to-be-measured concentration calculation unit 52 for calculating the concentration of the component to be measured in the dialysis drainage on the basis of the ratio of the concentration calculated by the ratio calculation unit 51 and the absorbance in the first wavelength measured by the absorbance measurement unit 3.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an apparatus and method for measuring components in a dialysis effluent. [Background technology]

[0002] In a blood purification device, blood is purified by contacting the blood with the dialysate through a blood purification membrane in a blood purifier (also called a dialyzer). If certain components in the blood leak too much into the dialysate, complications and other problems may occur. Therefore, to avoid such problems, it is desirable to monitor the concentrations of certain components in the dialysis effluent discharged from the blood purifier.

[0003] An example of a component (referred to as a component to be measured) in dialysis effluent that is desired to be monitored is albumin. Patent Document 1 discloses a method for measuring the concentration of albumin by optically exciting albumin in the solution and measuring the emitted fluorescence. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Special Publication No. 2014-518517 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the intensity of fluorescence is low, and measurement accuracy may be reduced, especially when the concentration of the component to be measured is low. For example, when the component to be measured is albumin, albumin is a component that should not leak too much from blood, so the albumin concentration is usually not expected to be very high. Therefore, it is desirable to measure the concentration of the component to be measured accurately even when the concentration is low.

[0006] Therefore, an object of the present invention is to provide a dialysis effluent component measuring device and method that can accurately measure the concentration of a target component in a dialysis effluent. [Means for solving the problem]

[0007] A dialysis effluent component measuring device according to one embodiment of the present invention is a device for measuring the concentration of a component to be measured contained in a dialysis effluent discharged from a blood purifier, wherein the component to be measured is a component that absorbs light of a first wavelength and is excited by light of the first wavelength to emit fluorescence of a second wavelength different from the first wavelength, and the dialysis effluent contains a measurement-inhibiting component that absorbs light of the first wavelength and is excited by light of the first wavelength to emit fluorescence of a third wavelength different from the first and second wavelengths, and the device comprises a light source that irradiates the dialysis effluent with light of the first wavelength, and a light intensity of transmitted light from the light source that has passed through the dialysis effluent is measured, and the concentration of the component to be measured is determined from the light intensity of the transmitted light and the light intensity of the light source. a first fluorescence measurement unit that measures the light intensity of the fluorescence of the second wavelength emitted by the analyte component upon excitation by light from the light source; a second fluorescence measurement unit that measures the light intensity of the fluorescence of the third wavelength emitted by the measurement-inhibiting component upon excitation by light from the light source; a ratio calculation unit that calculates the ratio of the concentration of the analyte component to the concentration of the measurement-inhibiting component contained in the dialysis effluent based on the measurement results of the first and second fluorescence measurement units; and a analyte component concentration calculation unit that calculates the concentration of the analyte component in the dialysis effluent based on the ratio of the concentrations calculated by the ratio calculation unit and the absorbance at the first wavelength measured by the absorbance measurement unit.

[0008] A dialysis effluent component measuring method according to one embodiment of the present invention is a method for measuring the concentration of a component to be measured contained in a dialysis effluent discharged from a blood purifier, wherein the component to be measured is a component that absorbs light of a first wavelength and is excited by the light of the first wavelength to emit fluorescence of a second wavelength different from the first wavelength, and the dialysis effluent contains a measurement-inhibiting component that absorbs light of the first wavelength and is excited by the first light to emit fluorescence of a third wavelength different from the first and second wavelengths, and the dialysis effluent is irradiated with light of the first wavelength from a light source, and a light intensity of transmitted light from the light source that has passed through the dialysis effluent is measured. the intensity of the fluorescence at the second wavelength emitted by the component to be measured upon excitation by the light from the light source; the intensity of the fluorescence at the third wavelength emitted by the component to be measured upon excitation by the light from the light source; the ratio of the concentration of the component to be measured to the concentration of the component to be measured contained in the dialysis effluent based on the measurement results of the fluorescence at the second and third wavelengths; and the concentration of the component to be measured in the dialysis effluent based on the calculated ratio of concentrations and the measured absorbance at the first wavelength. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a dialysis effluent component measuring device and method that can accurately measure the concentration of a component to be measured in a dialysis effluent. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a schematic diagram illustrating the configuration of a blood purification device using a dialysis effluent component measuring device according to one embodiment of the present invention. [Figure 2] (a) is a graph showing the absorption spectrum of the main filtered toxins contained in dialysis effluent, and (b) is a graph showing their fluorescence spectrum. [Figure 3] 1 is a schematic diagram of a dialysis effluent component measuring device according to one embodiment of the present invention. FIG. [Figure 4] FIG. 1 is a flow diagram of a method for measuring components in a dialysis effluent according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0011] [Embodiment Mode] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0012] (blood purification device) First, a blood purification apparatus using the dialysis effluent component measuring device according to the present embodiment will be described. Fig. 1 is a schematic diagram of a blood purification apparatus using the dialysis effluent component measuring device according to the present embodiment.

[0013] As shown in Fig. 1, a blood purification device 10 includes a blood circuit 11 for extracorporeally circulating a patient's blood, a liquid supply flow path 13 for supplying a supply liquid to a blood purifier 12 provided in the blood circuit 11, and a drainage flow path 14 for discharging drainage liquid from the blood purifier 12. In the example of Fig. 1, the liquid supply flow path 13 is shown as a dialysate flow path 13a for supplying dialysate to the blood purifier 12. However, the liquid supply flow path 13 is not limited to this, and may be a substitution fluid flow path for directly supplying substitution fluid to the blood circuit 11, or may have both the dialysate flow path 13a and a substitution fluid flow path.

[0014] The blood circuit 11 is composed of, for example, flexible tubes. In the blood circuit 11, a blood pump 111, a blood purifier 12, and an air trap chamber 112 are sequentially provided from the upstream side to the downstream side of the blood flow. The blood pump 111 is a liquid delivery pump that delivers blood. The air trap chamber 112 is used to remove air bubbles from the blood.

[0015] Dialysis water is supplied to the dialysate flow path 13a from an RO device (not shown) that produces clean dialysis water using a reverse osmosis (RO) membrane. Two types of dialysis solution stock solutions, stock solution A and stock solution B, are also supplied to the dialysate flow path 13a. Both stock solutions are stored in stock solution storage tanks 151, and stock solution A and stock solution B are supplied from the stock solution storage tanks 151 to the dialysate flow path 13a via stock solution flow paths 152. Each of the stock solution flow paths 152 is provided with a stock solution injection pump 153, which is a liquid feed pump that feeds stock solution A or stock solution B. Dialysis water is prepared in the dialysate flow path 13a by mixing stock solution A and stock solution B. The prepared dialysis solution is introduced into the blood purifier 12 via a duplex pump 16. However, the blood purification device 10 is not limited to this, and may be configured to supply a prepared dialysis solution stock solution, for example, a mixture of stock solutions A and B. Alternatively, the mechanism for preparing dialysis solution from dialysis water and dialysis solution stock solution may be omitted, and the dialysis solution may be supplied from an external source. In other words, the blood purification device 10 may be a personal dialysis device having a mechanism for preparing dialysis solution from dialysis water and dialysis solution stock solution, or a dialysis monitoring device supplied with dialysis solution from a multi-person dialysis solution supply device.

[0016] The dialysis effluent discharged from the blood purifier 12 is discharged through the drainage flow path 14. The duplex pump 16 is provided across the dialysate flow path 13a and the drainage flow path 14, and performs pumping operation so that the amount of dialysate introduced into the blood purifier 12 is equal to the amount of effluent discharged from the blood purifier 12. The drainage flow path 14 is also provided with a water removal flow path 14a that bypasses the duplex pump 16, and this water removal flow path 14a is provided with a water removal pump 17. When the water removal pump 17 is driven, the amount of effluent discharged from the blood purifier 12 becomes greater than the amount of dialysate introduced into the blood purifier 12, thereby removing water from the blood. The amount of water removed from the blood can be adjusted by adjusting the amount of fluid sent by the water removal pump 17.

[0017] A dialysis effluent component measuring device 1 according to this embodiment is provided in a drainage flow path 14 of a blood purification apparatus 10. The dialysis effluent component measuring device 1 is provided in the drainage flow path 14 downstream of the position where the water removal flow path 14a joins the drainage flow path 14. Note that the configuration in Fig. 1 is merely an example, and the specific configuration of the blood purification apparatus 10 can be changed as appropriate.

[0018] (Dialysis effluent component measuring device 1) The dialysis effluent component measuring device 1 is a device that measures the concentration of a specific analyte contained in the dialysis effluent discharged from the blood purifier 12. The analyte is a component that absorbs light of a first wavelength and, upon being excited by light of the first wavelength, emits fluorescence of a second wavelength different from the first wavelength. In this embodiment, the case where the analyte is albumin will be described. That is, the dialysis effluent component measuring device 1 is a device that measures the concentration of albumin in the dialysis effluent, for example. When the analyte is albumin, the first wavelength, which is the wavelength of the excitation light, is 250 nm or more and 330 nm or less, more preferably 275 nm or more and 285 nm or less. The second wavelength, which is the wavelength of the fluorescence emitted by albumin, is 300 nm or more and 400 nm or less.

[0019] However, the light intensity of fluorescent light is low, and it may be difficult to ensure sufficient detection accuracy, especially when the concentration of the analyte is low. To address this issue, the inventors considered using absorbance. When using absorbance, transmitted light is measured, making it possible to measure with sufficient light intensity even when the concentration of the analyte is low. However, absorbance alone may not provide sufficient measurement accuracy due to the influence of other components in the dialysis effluent.

[0020] Figure 2(a) shows the absorption spectra of the main filtered toxins contained in dialysis effluent, and Figure 2(b) shows their fluorescence spectra. As shown in Figure 2(a), the absorption spectrum of the target component, albumin, does not overlap with that of creatinine or urea, but does overlap with that of uric acid. Because uric acid absorbs light at a first wavelength (wavelength of 250 nm or more and 330 nm or less), it is difficult to accurately measure the concentration of the target component, albumin, simply by measuring the absorbance of light at the first wavelength due to the influence of uric acid.

[0021] On the other hand, as shown in FIG. 2(b), it can be seen that the wavelength of fluorescence (second wavelength) due to albumin is different from the wavelength of fluorescence due to uric acid. Thus, the dialysis effluent contains a measurement-inhibiting component that absorbs light of the first wavelength and, upon being excited by light of the first wavelength, emits fluorescence of a third wavelength different from the first and second wavelengths. When the component to be measured is albumin, uric acid corresponds to the measurement-inhibiting component. In this case, the third wavelength, which is the wavelength of the fluorescence of uric acid, is 380 nm or more and 480 nm or less. Here, a case where the measurement-inhibiting component is uric acid is described as an example, but the measurement-inhibiting component is not limited to uric acid as long as it corresponds to the component to be measured. Furthermore, two or more measurement-inhibiting components may be contained in the dialysis effluent.

[0022] Thus, when measuring the concentration of a component to be measured, if only fluorescence is used, there is a risk of measurement accuracy being reduced due to the low light intensity of the fluorescence, and if only absorbance is used, there is a risk of measurement accuracy being reduced due to the influence of components that inhibit measurement. The present inventors conducted extensive research based on these findings and arrived at the present invention.

[0023] FIG. 3 is a schematic diagram of a dialysis effluent component measuring device 1 according to this embodiment. As shown in FIG. 3, the dialysis effluent component measuring device 1 mainly comprises a light source 2, an absorbance measurement unit 3, a first fluorescence measurement unit 4, a second fluorescence measurement unit 6, and a calculation unit 5. The light source 2 irradiates the dialysis effluent with light of a first wavelength capable of exciting albumin, the component to be measured. Here, a light-emitting diode that irradiates ultraviolet light with a wavelength of 280 nm is used as the light source 2. In this embodiment, the light source 2 is pulse-driven so that light emission and non-emission are repeated at a predetermined cycle. This reduces power consumption and extends the life of the light-emitting diode used as the light source 2, and also makes it possible to suppress the effects of noise (the suppression of the effects of noise will be described later).

[0024] The drainage flow path 14 is provided with a flat, thin measuring section 14b formed to have a substantially uniform thickness. Here, the measuring section 14b is formed to have a substantially elliptical shape when viewed from the light source 2 side. The light source 2 is provided so as to face the center of the measuring section 14b in the thickness direction. The measuring section 14b is made of a material that transmits light of at least the first and second wavelengths (having sufficiently high transmittance for the first and second wavelengths). In addition, a lens 7 is provided between the light source 2 and the measuring section 14b. The light emitted from the light source 2 is focused by the lens 7 and enters the measuring section 14b. Here, the light from the light source 2 is converted by the lens 7 into parallel light which enters the measuring section 14b.

[0025] The absorbance measurement unit 3 measures the light intensity of transmitted light from the light source 2 that has passed through the dialysis effluent, and determines the absorbance at the first wavelength from the light intensity of the transmitted light and the light intensity of the light source 2. The absorbance measurement unit 3 has a transmitted light receiving element (PD) 31 that receives the transmitted light, and a lens 32 that collects the transmitted light and guides it to the transmitted light receiving element 31. Although not shown, the absorbance measurement unit 3 also has an absorbance calculation unit that calculates absorbance based on the light intensity of the transmitted light received by the transmitted light receiving element 31 and the light intensity of the light source 2. The absorbance calculation unit may be mounted on the calculation device 5, for example, or on a control board or the like separate from the calculation device 5, and is realized by an appropriate combination of a calculation element, a memory, software, an interface, and the like. Regarding the light intensity of the light source 2, for example, a light source measuring unit for measuring the light intensity of the light source 2 may be provided, and the measurement results of the light source measuring unit may be used, or a preset value (the light intensity of the light source 2 measured in advance) may be used.

[0026] The transmitted light receiving element 31 is preferably a photodiode that can detect even weak optical signals and has a fast response speed to incident light, and more preferably an avalanche photodiode. This makes it possible to capture changes in transmitted light over time and improves light receiving sensitivity due to its high multiplication factor even for small amounts of light. The transmitted light receiving element 31 is positioned opposite the light source 2, with the measuring unit 14b in between.

[0027] The lens 32 is disposed between the transmitted light receiving element 31 and the measurement unit 14b. Although not shown, the absorbance measurement unit 3 may be configured to guide the light collected by the lens 32 to the transmitted light receiving element 31 through a filter that blocks light of the second and third wavelengths and passes light of the first wavelength. In this case, the filter may be a bandpass filter that passes light of the emission wavelength of the light source 2, and is preferably configured to pass light with a wavelength of 250 nm or more and 330 nm or less, more preferably 275 nm or more and 285 nm or less. This makes it possible to remove fluorescence (and light that becomes noise) due to albumin and uric acid from the light collected by the lens 32, enabling more accurate measurements.

[0028] In this embodiment, the light source 2 is pulse-driven to repeatedly emit and not emit light at a predetermined cycle, but the absorbance measurement unit 3 may be configured to measure the difference in the intensity of light received when the light source 2 is emitting and not emitting light as the light intensity of transmitted light. By extracting only the light-receiving component at a predetermined cycle in the signal processing unit (arithmetic unit 5), the influence of noise can be suppressed, enabling more accurate measurements.

[0029] The first fluorescence measurement unit 4 measures the intensity of fluorescence emitted by albumin, which is the component to be measured, and measures the intensity of fluorescence at a second wavelength emitted by albumin upon excitation by light from the light source 2. The first fluorescence measurement unit 4 has a first fluorescence photoreceptor (PD) 41, a first filter 42, and a first lens 43 serving as a first light-guiding member that guides fluorescence generated in the dialysis effluent (i.e., generated in the measurement unit 14b) to the first fluorescence photoreceptor 41. The first filter 42 is provided between the measurement unit 14b and the first fluorescence photoreceptor 41, and blocks light at the first wavelength (transmitted light and scattered light) and light at the third wavelength (fluorescence due to uric acid) from entering the first fluorescence photoreceptor 41, while allowing only light at the second wavelength due to the fluorescence of albumin to pass through. The first filter 42 may be a bandpass filter that passes light having a wavelength of 300 nm or more and 400 nm or less, the same as the second wavelength, and more preferably a bandpass filter that passes light having a wavelength in a wavelength range around 340 nm, which is the fluorescence wavelength of albumin (for example, 330 nm or more and 350 nm or less). Because the light intensity of fluorescence is relatively low, this embodiment is configured so that light collected by the first lens 43 is received by the first fluorescence light-receiving element 41. The first lens 43 is provided between the measurement unit 14b and the first filter 42.

[0030] The second fluorescence measurement unit 6 is used to measure the light intensity of fluorescence due to uric acid, a measurement-inhibitory component, and measures the light intensity of fluorescence at a third wavelength emitted by uric acid upon excitation by light from the light source 2. The second fluorescence measurement unit 6 has a second fluorescence photodetector (PD) 61, a second filter 62, and a second lens 63 as a second light-guiding member that guides fluorescence generated in the dialysis effluent (i.e., generated in the measurement unit 14b) to the second fluorescence photodetector 61. The second filter 62 is provided between the measurement unit 14b and the second fluorescence photodetector 61, and blocks light of the first wavelength (transmitted light and scattered light) and light of the second wavelength (fluorescence due to albumin) from entering the second fluorescence photodetector 61, while allowing only light of the third wavelength due to the fluorescence of uric acid to pass through. The second filter 62 may be a bandpass filter that passes light having a wavelength of 380 nm or more and 480 nm or less, the same as the third wavelength, and more preferably a bandpass filter that passes light having a wavelength in a wavelength range around 430 nm, which is the fluorescent wavelength of uric acid (for example, 420 nm or more and 440 nm or less). Since the light intensity of fluorescent light is relatively low, in this embodiment, the light collected by the second lens 63 is received by the second fluorescent light receiving element 61. The second lens 63 is provided between the measurement unit 14b and the second filter 62.

[0031] As with the transmitted light photoreceptor 31, the first fluorescent light photoreceptor 41 and the second fluorescent light photoreceptor 61 should preferably be photodiodes capable of detecting weak optical signals and having a fast response speed to incident light, or more preferably, avalanche photodiodes, which make it possible to capture changes in the fluorescent light over time and, because of their high multiplication factor even for minute light amounts, improve the light receiving sensitivity.

[0032] Furthermore, in this embodiment, the light source 2 is pulse-driven to repeatedly emit and not emit light at a predetermined cycle, but the first fluorescence measurement unit 4 and the second fluorescence measurement unit 6 may be configured to measure the difference in light intensity between when the light source 2 is emitting light and when it is not emitting light as the light intensity due to fluorescence. By extracting only the light-receiving component at a predetermined cycle in the signal processing unit (arithmetic device 5), the influence of noise can be suppressed, enabling more accurate measurements to be performed.

[0033] The calculation device 5 is equipped with a ratio calculation section 51, a metered component concentration calculation section 52, a metered component leakage amount calculation section 53, an alarm section 54, and a memory section 55. The ratio calculation section 51, the metered component concentration calculation section 52, the metered component leakage amount calculation section 53, and the alarm section 54 are realized by appropriately combining a calculation element, a memory, software, an interface, a storage device such as a hard disk, etc. The memory section 55 is realized using a predetermined storage area in a storage device such as a memory or a hard disk. The calculation device 5 may be, for example, a control device of the blood purification apparatus 10.

[0034] The ratio calculation unit 51 calculates the ratio between the concentration of the measurement target component (here, albumin) contained in the dialysis effluent and the concentration of the measurement-inhibiting component (here, uric acid) based on the measurement results of the first fluorescence measurement unit 4 and the second fluorescence measurement unit 6. That is, the ratio calculation unit 51 calculates the ratio between the concentrations of albumin and uric acid by comparing the light intensity of the fluorescence due to albumin with the light intensity of the fluorescence due to uric acid (for example, by calculating the ratio of the light intensities).

[0035] The analyte concentration calculation unit 52 calculates the concentration of the analyte (here, albumin) in the dialysis effluent based on the ratio between the albumin and uric acid concentrations calculated by the ratio calculation unit 51 and the absorbance at the first wavelength measured by the absorbance measurement unit 3. The absorbance measured by the absorbance measurement unit 3 is affected by both albumin and uric acid (see FIG. 2(a)). Therefore, by taking into account the ratio between the albumin and uric acid concentrations, it is possible to calculate the albumin concentration by separating only the effect of albumin.

[0036] The measurement component leakage amount calculation unit 53 calculates the leakage amount of the measurement component since the start of treatment based on the concentration of the measurement component (here, albumin) calculated by the measurement component concentration calculation unit 52 and the flow rate of the dialysis effluent. The flow rate of the dialysis effluent may be calculated from the drive amount of the duplex pump 16 and the ultrafiltration pump 17, or may be measured by providing a flow rate sensor in the drainage flow path 14.

[0037] More specifically, measurement component leakage amount calculation unit 53 calculates the average albumin concentration for one minute, and multiplies the average albumin concentration by the flow rate of the dialysis effluent to calculate the albumin leakage amount per minute, and stores this amount for each minute in memory unit 55. Then, by adding up all the albumin leakage amounts per minute stored in memory unit 55 for the entire elapsed treatment time, the leakage amount of the measurement component from the start of treatment is calculated.

[0038] When the albumin concentration calculated by analyte concentration calculation unit 52 is equal to or greater than a preset threshold, alarm unit 54 issues an alarm by appropriate means such as light, sound, or display. In this embodiment, when the amount of albumin leakage calculated by analyte leakage amount calculation unit 53 is equal to or greater than a preset threshold, alarm unit 54 issues an alarm by appropriate means such as light, sound, or display.

[0039] (Method for measuring components in dialysis effluent) 4 is a flow diagram of the method for measuring components in a dialysis effluent according to this embodiment. For example, the flow of FIG. 4 starts at the start of blood purification treatment.

[0040] 4, in the method for measuring components in a dialysis effluent according to this embodiment, first, in step S1, light of a first wavelength (here, a wavelength of 280 nm) is irradiated onto the dialysis effluent from the light source 2, and in step S2, the transmitted light is received by the transmitted light receiving element 31 of the absorbance measurement unit 3, the light intensity is measured, and the absorbance at the first wavelength is determined. Also, the first fluorescence light receiving element 41 of the first fluorescence measurement unit 4 measures the light intensity of fluorescence of a second wavelength due to the component to be measured (here, albumin), and the second fluorescence light receiving element 61 of the second fluorescence measurement unit 6 measures the light intensity of fluorescence of a third wavelength due to a measurement-inhibiting component (here, uric acid).

[0041] Then, in step S3, the ratio calculation unit 51 calculates the ratio of the concentration of the measurement target component (here, albumin) contained in the dialysis effluent to the concentration of the measurement-inhibiting component (here, uric acid) based on the measurement results of the first and second fluorescence measurement units 4 and 6. In this embodiment, the ratio of the concentrations of albumin and uric acid is calculated by comparing the light intensity of the fluorescence at the second wavelength (340 nm) due to albumin with the light intensity of the fluorescence at the third wavelength (430 nm) due to uric acid.

[0042] Thereafter, in step S4, the measurement component concentration calculation unit 52 calculates the concentration of the measurement component (here, albumin) in the dialysis effluent based on the ratio of the concentrations calculated in step S3 and the absorbance measured in step S2 by the absorbance measurement unit 3. The calculated albumin concentration is stored in the memory unit 55.

[0043] Thereafter, in step S5, the alarm unit 54 determines whether the albumin concentration determined in step S4 is equal to or greater than a preset threshold. If the determination in step S5 is YES (Y), an alarm is issued using light, sound, or the like in step S6, and the process proceeds to step S7. If the determination in step S5 is NO (N), the process proceeds to step S7 without issuing an alarm.

[0044] In step S7, the measurement component leakage calculation unit 53 calculates the leakage amount of the measurement component since the start of treatment based on the albumin concentration determined in step S4 and the flow rate of the dialysis effluent. More specifically, as described above, the measurement component leakage calculation unit 53 calculates the average albumin concentration for one minute, and multiplies the average albumin concentration by the flow rate of the dialysis effluent to calculate the albumin leakage amount per minute, which is stored in the memory unit 55 for each minute. The albumin leakage amount per minute stored in the memory unit 55 is then added up over the entire elapsed treatment time to calculate the albumin leakage amount since the start of treatment.

[0045] Thereafter, in step S8, the alarm unit 54 determines whether the amount of albumin leakage determined in step S7 is equal to or greater than a preset threshold. If the determination in step S8 is YES (Y), an alarm is issued using light, sound, or the like in step S9, and the process proceeds to step S10. If the determination in step S8 is NO (N), the process proceeds to step S10 without issuing an alarm.

[0046] In step S10, the calculation device 5 determines whether the treatment has ended. Whether the treatment has ended can be determined, for example, by a signal from a dialysis control device. If the determination in step S10 is NO (N), the process returns to step S1 and continues to monitor the albumin concentration in the dialysis effluent. If the determination in step S10 is YES (Y), the process ends.

[0047] (Actions and Effects of the Embodiments) As described above, in the dialysis effluent component measuring device 1 according to this embodiment, the component to be measured is a component that absorbs light of a first wavelength and is excited by light of the first wavelength to emit fluorescence of a second wavelength different from the first wavelength, and the dialysis effluent contains a measurement-inhibiting component that absorbs light of the first wavelength and is excited by light of the first wavelength to emit fluorescence of a third wavelength different from the first and second wavelengths, and the device comprises a light source 2 that irradiates the dialysis effluent with light of the first wavelength, an absorbance measuring unit 3 that measures the light intensity of transmitted light from the light source 2 that has passed through the dialysis effluent and determines the absorbance at the first wavelength from the light intensity of the transmitted light and the light intensity of the light source 2, and a light source 3 that measures the light intensity of the transmitted light and the light intensity of the light source 2. The device is equipped with a first fluorescence measurement unit 4 that measures the light intensity of fluorescence at a second wavelength emitted by the measured component when excited by light from the light source 2, a second fluorescence measurement unit 6 that measures the light intensity of fluorescence at a third wavelength emitted by the measurement-inhibiting component when excited by light from the light source 2, a ratio calculation unit 51 that calculates the ratio of the concentration of the measured component to the concentration of the measurement-inhibiting component contained in the dialysis effluent based on the measurement results of the first and second fluorescence measurement units 4 and 6, and a measured component concentration calculation unit 52 that calculates the concentration of the measured component in the dialysis effluent based on the concentration ratio calculated by the ratio calculation unit 51 and the absorbance at the first wavelength measured by the absorbance measurement unit 3.

[0048] As a result, even when the concentration of the component to be measured is low and the light intensity of the fluorescence is low, the concentration of the component to be measured can be measured based on the light intensity of the transmitted light that ensures sufficient light intensity (more specifically, based on the absorbance calculated from the light intensity of the transmitted light), thereby improving the accuracy of measuring the concentration of the component to be measured.Furthermore, by calculating the ratio of the concentrations of the component to be measured and the measurement-inhibiting component using fluorescence, which makes it easy to distinguish between them, and then taking this ratio into consideration, the concentration of the component to be measured can be calculated based on the absorbance, thereby eliminating the influence of the measurement-inhibiting components and accurately measuring the concentration of the component to be measured.

[0049] (Summary of the embodiment) Next, the technical ideas grasped from the above-described embodiments will be described by using the reference numerals and the like in the embodiments. However, the reference numerals and the like in the following description do not limit the components in the claims to the members and the like specifically shown in the embodiments.

[0050] [1] An apparatus for measuring the concentration of a component to be measured contained in a dialysis effluent discharged from a blood purifier (12), wherein the component to be measured is a component that absorbs light of a first wavelength and is excited by the light of the first wavelength to emit fluorescence at a second wavelength different from the first wavelength, and the dialysis effluent contains a measurement-inhibiting component that absorbs light of the first wavelength and is excited by the light of the first wavelength to emit fluorescence at a third wavelength different from the first and second wavelengths, the apparatus comprising: a light source (2) that irradiates the dialysis effluent with light of the first wavelength; an absorbance measurement unit (3) that measures the light intensity of transmitted light from the light source (2) that has passed through the dialysis effluent and determines the absorbance at the first wavelength from the light intensity of the transmitted light and the light intensity of the light source; a second fluorescence measurement unit (6) that measures the intensity of fluorescence at the third wavelength emitted by the measurement-inhibiting component upon excitation by light from the light source (2); a ratio calculation unit (51) that calculates a ratio between the concentration of the measurement-inhibiting component contained in the dialysis effluent and the concentration of the measurement-inhibiting component based on the measurement results of the first and second fluorescence measurement units (4, 6); and a measurement-inhibiting component concentration calculation unit (52) that calculates the concentration of the measurement-inhibiting component in the dialysis effluent based on the ratio of the concentrations calculated by the ratio calculation unit (51) and the absorbance at the first wavelength measured by the absorbance measurement unit (3).

[0051] [2] The dialysis effluent component measuring device (1) according to [1], wherein the component to be measured is albumin and the measurement-inhibiting component is uric acid.

[0052] [3] The dialysis effluent component measuring device (1) according to [2], wherein the first wavelength is 250 nm or more and 330 nm or less, the second wavelength is 300 nm or more and 400 nm or less, and the third wavelength is 380 nm or more and 480 nm or less.

[0053] [4] The dialysis effluent component measuring device (1) according to any one of [1] to [3], wherein the first fluorescence measurement unit (4) has a first fluorescence light receiving element (41) and a first filter (42) that blocks light of the first wavelength and the third wavelength from being incident on the first fluorescence light receiving element (41) and transmits light of the second wavelength, and the second fluorescence measurement unit (6) has a second fluorescence light receiving element (61) and a second filter (62) that blocks light of the first wavelength and the second wavelength from being incident on the second fluorescence light receiving element (61) and transmits light of the third wavelength.

[0054] [5] The dialysis effluent component measuring device (1) according to [4], wherein the first fluorescence measurement unit (4) has a first light-guiding member (43) that guides the fluorescence generated in the dialysis effluent to the first fluorescence light-receiving element (41), and the second fluorescence measurement unit (6) has a second light-guiding member (63) that guides the fluorescence generated in the dialysis effluent to the second fluorescence light-receiving element (61).

[0055] [6] The dialysis effluent component measuring device (1) according to any one of [1] to [5], wherein the light source (2) repeats emission and non-emission at a predetermined cycle, the absorbance measuring unit (3) measures the difference in the intensity of light received when the light source is emitting light and when it is not emitting light as the light intensity of the transmitted light, and the first and second fluorescence measuring units (4, 6) measure the difference in the intensity of light received when the light source is emitting light and when it is not emitting light as the light intensity of the fluorescence.

[0056] [7] A method for measuring the concentration of a target component contained in a dialysis effluent discharged from a blood purifier (12), wherein the target component is a component that absorbs light of a first wavelength and is excited by the light of the first wavelength to emit fluorescence of a second wavelength different from the first wavelength, and the dialysis effluent contains a measurement-inhibiting component that absorbs light of the first wavelength and is excited by the first light to emit fluorescence of a third wavelength different from the first and second wavelengths, the method comprising: irradiating the dialysis effluent with light of the first wavelength from a light source (2); measuring the light intensity of the transmitted light from the light source (2) that has passed through the dialysis effluent; and comparing the light intensity of the transmitted light with a previous measurement. a measurement result of the fluorescence at the second wavelength and the measurement-inhibiting component emitted by the measurement target component; a measurement result of the fluorescence at the third wavelength and the measurement-inhibiting component emitted by the measurement target component; a calculation result of the ratio of the concentrations of the measurement target component and the measurement-inhibiting component contained in the dialysis effluent based on the measurement result of the fluorescence at the second and third wavelengths; and a calculation result of the ratio of the concentrations of the measurement target component and the measurement-inhibiting component contained in the dialysis effluent based on the calculated ratio of the concentrations and the measured absorbance at the first wavelength.

[0057] Although the embodiments of the present invention have been described above, the invention according to the claims is not limited to the above-described embodiments. It should be noted that not all of the combinations of features described in the embodiments are necessarily essential to the means for solving the problems of the invention. Furthermore, the present invention can be appropriately modified and implemented within the scope of its spirit. [Explanation of symbols]

[0058] 1...Dialysis waste fluid component measuring device 2…Light source 3...Absorbance measuring section 31...Transmitted light receiving element 4...First fluorescence measurement unit 41...First fluorescent light receiving element 42...First filter 43...First lens (first light guide member) 5...Arithmetic device 51...Ratio calculation section 52...Measurement component concentration calculation section 53...Measurement component leakage calculation section 54...Alarm section 6...Second fluorescence measurement unit 61...second fluorescent light receiving element 62...Second filter 63...Second lens (second light guide member) 10...Blood purification device 12...Blood purifier

Claims

1. An apparatus for measuring the concentration of a target component contained in dialysis wastewater discharged from a blood purifier, the component to be measured is a component that absorbs light of a first wavelength and is excited by the light of the first wavelength to emit fluorescence of a second wavelength different from the first wavelength, the dialysis effluent contains a measurement-inhibiting component that absorbs light of the first wavelength and is excited by light of the first wavelength to emit fluorescence of a third wavelength different from the first and second wavelengths; a light source that irradiates the dialysis effluent with light of the first wavelength; an absorbance measurement unit that measures the light intensity of transmitted light from the light source that has passed through the dialysis effluent, and calculates the absorbance at the first wavelength from the light intensity of the transmitted light and the light intensity of the light source; a first fluorescence measurement unit that measures the light intensity of the fluorescence of the second wavelength emitted by the component to be measured upon excitation by the light from the light source; a second fluorescence measurement unit that measures the light intensity of the fluorescence of the third wavelength emitted by the measurement-inhibiting component upon excitation by light from the light source; a ratio calculation unit that calculates a ratio between the concentration of the measurement target component and the concentration of the measurement inhibiting component contained in the dialysis effluent based on the measurement results of the first and second fluorescence measurement units; and a measurement component concentration calculation unit that calculates the concentration of the measurement component in the dialysis effluent based on the concentration ratio calculated by the ratio calculation unit and the absorbance at the first wavelength measured by the absorbance measurement unit. Dialysis effluent component measuring device.

2. the component to be measured is albumin, The measurement-inhibiting component is uric acid. The dialysis effluent component measuring device according to claim 1.

3. the first wavelength is equal to or greater than 250 nm and equal to or less than 330 nm, the second wavelength is 300 nm or more and 400 nm or less, the third wavelength is 380 nm or more and 480 nm or less; The dialysis effluent component measuring device according to claim 2.

4. the first fluorescence measurement unit includes a first fluorescence light-receiving element and a first filter that blocks light of the first wavelength and the third wavelength from being incident on the first fluorescence light-receiving element and transmits light of the second wavelength; the second fluorescence measurement unit includes a second fluorescence light-receiving element and a second filter that blocks light of the first wavelength and the second wavelength from being incident on the second fluorescence light-receiving element and transmits light of the third wavelength. The dialysis effluent component measuring device according to any one of claims 1 to 3.

5. the first fluorescence measurement unit has a first light guiding member that guides the fluorescence generated in the dialysis effluent to the first fluorescence light receiving element, the second fluorescence measurement unit has a second light guiding member that guides the fluorescence generated in the dialysis effluent to the second fluorescence light receiving element. The dialysis effluent component measuring device according to claim 4.

6. the light source repeats light emission and non-light emission at a predetermined cycle; the absorbance measurement unit measures a difference between the received light intensity when the light source emits light and when it does not emit light as the light intensity of the transmitted light; The first and second fluorescence measurement units measure a difference in received light intensity between when the light source emits light and when it does not emit light as the light intensity due to the fluorescence. The dialysis effluent component measuring device according to any one of claims 1 to 5.

7. A method for measuring the concentration of a target component contained in a dialysis effluent discharged from a blood purifier using a dialysis effluent component measuring device, comprising: the component to be measured is a component that absorbs light of a first wavelength and is excited by the light of the first wavelength to emit fluorescence of a second wavelength different from the first wavelength, the dialysis effluent contains a measurement-inhibiting component that absorbs light of the first wavelength and is excited by the first light to emit fluorescence of a third wavelength different from the first and second wavelengths; The device, irradiating the dialysis effluent with light of the first wavelength from a light source; measuring the intensity of light transmitted from the light source through the dialysis effluent, and calculating the absorbance at the first wavelength from the intensity of the transmitted light and the intensity of the light source; measuring the light intensity of the fluorescence of the second wavelength emitted by the component to be measured upon excitation by the light from the light source; measuring the light intensity of the fluorescence of the third wavelength emitted by the measurement-inhibiting component upon excitation by the light from the light source; calculating a ratio of the concentration of the measurement target component contained in the dialysis effluent to the concentration of the measurement inhibiting component based on the measurement results of the fluorescence of the second and third wavelengths; calculating a concentration of the measured component in the dialysis effluent based on the ratio of the calculated concentrations and the measured absorbance at the first wavelength; Method for measuring components in dialysis effluent.

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