Sampling device and filtration unit

Abstract

To appropriately and easily sample a sampling target such as environmental DNA.SOLUTION: A sampling device 1 comprises a filtration unit 100 and a base unit 200 to which the filtration unit 100 can be detachably attached. The filtration unit 100 includes a filter 102 that filters a liquid containing a sampling target, and a configuration for supplying a fixative that fixes the sampling target remaining on the filter 102 after filtration of the liquid. The base unit 200 includes a housing 201 to which the filtration unit 100 is attached; a configuration which is provided on the housing 201 for discharging or storing, outside the device, the liquid filtered through the filter 102 of the filtration unit 100 attached to the housing; and a configuration which is provided on the housing 201 for enabling filtration by the filter 102 and supply of the fixative in the filtration unit 100 attached to the housing 201.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a collection device and a filtration unit included in the collection device. [Background technology]

[0002] BACKGROUND ART Conventionally, a method of filtering a liquid containing environmental DNA (deoxyribonucleic acid) has been proposed as a method for collecting environmental DNA (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-101225 Summary of the Invention [Problem to be solved by the invention]

[0004] To analyze the environmental DNA obtained by filtration, for example, the filtered filter with the residue containing environmental DNA is removed from the filtration device and transported to the analysis site. When attaching and removing the filter, care must be taken to prevent DNA contamination from the external environment. For example, it is necessary to use properly cleaned equipment and tools and wear gloves during the procedure. These procedures must also be performed in a sterile environment. The above-mentioned care is also necessary when fixing the residue on the filtered filter with a fixative reagent to prevent degradation of the collected DNA.

[0005] Furthermore, the filtration equipment must be cleaned after each collection of environmental DNA, i.e., after each filtration. Furthermore, the operation of the filtration equipment requires a worker with specialized collection skills. Without such a worker, it is difficult to properly collect environmental DNA.

[0006] The present invention has been made in view of the above, and aims to provide a collection device and a filtration unit that can appropriately and easily collect collection targets such as environmental DNA. [Means for solving the problem]

[0007] In order to achieve the above-mentioned object, the collection device of the present invention is a collection device including a filtration unit and a base unit to which the filtration unit can be detachably attached, wherein the filtration unit has a filter that filters a liquid containing a collection target and a configuration that supplies a fixing reagent that fixes the collection target remaining in the filter that has filtered the liquid, and the base unit has a housing to which the filtration unit is attached, a configuration provided in the housing that discharges or stores the liquid filtered by the filter discharged from the filtration unit attached to the housing outside the device, and a configuration provided in the housing that enables filtration by the filter and supply of a fixing reagent in the filtration unit attached to the housing.

[0008] With the collection device of the present invention, the entire filtration unit can be removed from the base unit after filtration. Therefore, for example, the entire filtration unit can be transported to an analysis location. This eliminates the above-mentioned problems that arise when only the filter is attached and detached at the time of collection of environmental DNA, i.e., at the time of filtration. Therefore, the collection device of the present invention allows collection targets, such as environmental DNA, to be collected appropriately and easily.

[0009] The filtration unit may further include a pipe for discharging the liquid and the fixing reagent that have passed through the filter, a valve provided in the pipe, and a control device that opens the valve when the filter filters the liquid and closes the valve when the fixing reagent passes through the filter. With this configuration, the collection target remaining on the filter can be more appropriately fixed by the fixing reagent.

[0010] The piping may be flexible and have a variable volume. With this configuration, the collection target substance remaining on the filter can be more appropriately fixed by the fixing reagent.

[0011] The base unit may further include a sensor for detecting the properties of the liquid discharged from the filtration unit attached to the base unit after filtration by the filter. With this configuration, information indicating the properties of the filtered liquid can be obtained in addition to collecting the sample.

[0012] The filtration unit may further include a storage device that stores the detection results of the sensor. With this configuration, the filtration unit stores information indicating the collected sample and the properties of the liquid after filtration, thereby improving convenience.

[0013] The base unit may be configured to enable filtration by a filter and supply of a fixing reagent, and may include a configuration for operating the filtration and supply. With this configuration, the sample to be sampled can be sampled by operating the configuration provided in the base unit.

[0014] Furthermore, the filtration unit included in the collection device according to the present invention has a novel configuration and is an invention in itself. [Effects of the Invention]

[0015] According to the present invention, it is possible to appropriately and easily collect a collection target such as environmental DNA. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a diagram showing the appearance of a collection device according to an embodiment of the present invention, and a filtration unit and a base unit included in the collection device. [Figure 2] 1 is a diagram showing the internal configuration of a filtration unit and a base unit included in a collection device according to an embodiment of the present invention. FIG. [Figure 3]10A and 10B are diagrams illustrating an example of supplying a fixing reagent in a filtration unit according to an embodiment of the present invention. [Figure 4] FIG. 10 is a diagram for explaining an example of supplying a fixing reagent. DETAILED DESCRIPTION OF THE INVENTION

[0017] Hereinafter, an embodiment of a collection device and a filtration unit according to the present invention will be described in detail with reference to the drawings. In the description of the drawings, the same elements are designated by the same reference numerals, and duplicated explanations will be omitted. Furthermore, the dimensional proportions of the drawings do not necessarily correspond to those in the description.

[0018] FIG. 1(a) shows the appearance of a sampling device 1 according to this embodiment. The sampling device 1 is a device (system) that samples a sample from a liquid containing the sample. The sample sampled by the sampling device 1 is, for example, environmental DNA derived from living organisms. When the sample is environmental DNA, the liquid (suspended matter) containing the sample is water, more specifically, water (environmental water) such as ocean, river, or lake water. By sampling environmental DNA, for example, ecosystem monitoring can be performed. In the following description, an example is used in which environmental DNA is sampled from environmental water. However, the sample may be something other than environmental DNA, such as RNA (ribonucleic acid). Furthermore, the liquid containing the sample may be something other than environmental water that corresponds to the sample.

[0019] The sampling device 1 enables appropriate and easy collection of environmental DNA at sites where environmental water is obtained, such as on land or at sea (on a ship), even by workers who do not have specialized skills or knowledge in collecting environmental DNA. The sampling device 1 filters environmental water and collects (filters and collects, or concentrates) environmental DNA as a residue (filtrate).

[0020] Next, the configuration of the collection device 1 according to this embodiment will be described. The collection device 1 includes a filtration unit 100 and a base unit 200. Fig. 1(b) shows the appearance of the filtration unit 100, and Fig. 1(c) shows the appearance of the base unit 200. Fig. 2 shows the internal configuration of the filtration unit 100 and the base unit 200.

[0021] The filtration unit 100 can be attached to the base unit 200. This attachment constitutes the collection device 1. The filtration unit 100 can also be detached from the base unit 200. That is, the filtration unit 100 and the base unit 200 are configured to be detachable.

[0022] The environmental DNA collected by the collection device 1 is held in the filtration unit 100. After collecting environmental DNA using the collection device 1, the operator removes the filtration unit 100 from the base unit 200 and transports the filtration unit 100 to the analysis location. If it takes time to transport the filtration unit 100 to the analysis location, the filtration unit 100 may be stored in a refrigerator or the like. Therefore, if environmental DNA is to be collected multiple times, a number of filtration units 100 should be prepared in advance, corresponding to the number of times the environmental DNA will be collected.

[0023] The filtration unit 100 is a device that filters a liquid containing a collection target and holds the collection target obtained by filtration. The filtration unit 100 also fixes the collection target obtained by filtration with a fixing reagent.

[0024] The filtration unit 100 includes a housing 101. A configuration for performing filtration and supplying a fixing reagent is provided inside the housing 101. The housing 101 of the filtration unit 100 has, for example, a substantially rectangular parallelepiped shape as shown in FIG. 1(b).

[0025] As shown in Fig. 2, the filtration unit 100 includes a filter 102 that filters environmental water. A conventional hydrophilic filter that does not allow environmental DNA to pass through but allows environmental water to pass through can be used as the filter 102. Note that "conventional" also includes those that utilize conventional technology (the same applies hereinafter).

[0026] For example, a commercially available cartridge filter such as Sterivex manufactured by Merck Millipore, as shown in FIG. 3(a), may be used as the filter 102. This filter 102 is cylindrically disposed inside a cylindrical filter unit 103. In FIG. 3, the interior of the cylindrical filter 102 is hatched. In the cartridge filter shown in FIG. 3(a), environmental water flows into the cylindrical filter unit 103, is filtered by the cylindrical filter 102, and the filtered environmental water is discharged from the inside of the cylinder. Note that the filter 102 used for filtration does not necessarily have to have the above configuration, and any filter that can be used for collecting environmental DNA may be used.

[0027] Filtration unit 100 is configured to filter environmental water and includes a liquid delivery system including filter 102, main pump 104, valve 105, and valve 106. Main pump 104 and valve 105 are provided before filter 102 in the flow path of the environmental water. Valve 106 is provided after filter 102 in the flow path of the environmental water. Main pump 104 is a pump that pushes environmental water into filter 102. A conventional liquid delivery pump such as a diaphragm pump, a peristaltic pump, or a syringe-type pump having a movable piston and cylinder can be used as main pump 104.

[0028] Valve 105 is a valve that opens and closes the liquid flow path before filter 102. Valve 106 is a valve that opens and closes the liquid flow path after filter 102. Conventional electromagnetic valves can be used as valves 105 and 106. Valves 105 and 106 may also be switching valves that are electromagnetic valves or air valves whose opening and closing is controlled in conjunction with the operation of a plunger. Furthermore, the switching valves may be two-way valves or three-way valves.

[0029] The main pump 104, valve 105, filter 102, and valve 106 are connected by piping through which liquid flows in this order. A piping leading to the outside of the filtration unit 100 is connected to the main pump 104 so that environmental water can flow in from the outside. For example, the filtration unit 100 is configured so that a sample water bottle (tank) 300 containing environmental water can be connected to this piping, allowing the environmental water contained in the sample water bottle 300 to flow in. A piping (drain line) leading to the outside of the filtration unit 100 is connected to the valve 106 so that the liquid filtered by the filter 102 can be discharged to the outside. Conventional piping can be used (the same applies to the piping below).

[0030] Environmental water flowing into filtration unit 100 is pushed into filter 102 by main pump 104, filtered by filter 102, and discharged from filtration unit 100. When filtration is performed by filter 102, valves 105 and 106 are open. Note that the configuration of filtration unit 100, including filter 102 for filtering environmental water, may be other than that described above, as long as it is capable of filtering in a manner that allows environmental DNA to be collected.

[0031] The filtration unit 100 is configured to supply a fixation reagent that fixes environmental DNA remaining on the filter 102 (collected in the filter 102) after filtering environmental water. The fixation reagent is a liquid reagent that prevents DNA degradation. Conventional fixation reagents can be used. Note that the fixation reagent may be one that is suitable for the collection target other than those described above, as long as it fixes the collection target remaining on the filter 102.

[0032] The filtration unit 100 is configured to supply a fixing reagent, and is equipped with a reagent container 107 for the fixing reagent and a sub-pump 108. The reagent container 107 is a container that contains the fixing reagent to be supplied to the filter 102 in which environmental DNA remains. The reagent container 107 already contains the fixing reagent when the filtration unit 100 is used (when environmental DNA is collected). A conventional reagent container can be used as the reagent container 107.

[0033] The secondary pump 108 is a pump that pushes the immobilization reagent into the filter 102. As the secondary pump 108, a conventional liquid-transfer pump such as a diaphragm pump, a peristaltic pump, or a syringe-type pump having a movable piston and cylinder can be used.

[0034] A pipe for the fixing reagent is provided between the reagent container 107 and the sub-pump 108 so as to enable supply of the fixing reagent. In addition, a pipe for the fixing reagent is provided between the pipe between the valve 105 and the filter 102 and the sub-pump 108 so as to enable supply of the fixing reagent.

[0035] When a fixing reagent is supplied to the filter 102 on which environmental DNA remains after filtering environmental water, the fixing reagent contained in the reagent container 107 is pushed out to the filter 102 by the sub-pump 108. A portion of the supplied fixing reagent acts on the environmental DNA remaining on the filter 102 to fix it. The remainder of the supplied fixing reagent passes through the filter 102 and is discharged from the filtration unit 100. The fixing reagent that has passed through the filter 102, like the filtered environmental water, is discharged from the filtration unit 100 through a pipe connected to the outside of the filtration unit 100. Note that the configuration of the filtration unit 100 for supplying a fixing reagent to the filter 102 on which environmental DNA remains after filtration may be other than that described above.

[0036] The filtration unit 100 includes a control circuit 109. The control circuit 109 is a control device that controls the filtration of the liquid and the supply of the fixing reagent. The control circuit 109 is connected to the main pump 104, valves 105, 106, and sub-pump 108 so as to control these. The control circuit 109 controls the filtration of the environmental water and the supply of the fixing reagent in accordance with a control method (an operation sequence for filtration and supply of the fixing reagent) pre-stored in a memory 109a included in the control circuit 109. The control method stored in the control circuit 109 corresponds to the characteristics of the filtration unit 100 (e.g., the number of filters 102, the filtration volume, the filtration flow rate, and the amount of fixation reagent introduced). Conventional hardware used for controlling equipment can be used for the control circuit 109.

[0037] The control circuit 109 controls each component of the filtration unit 100 so that the filtration of the environmental water and the supply of the fixing reagent are performed automatically. When filtering the environmental water, the control circuit 109 opens the valves 105 and 106 and operates the main pump 104 via the motor driver 110 to push the environmental water contained in the sample water bottle 300 to the filter 102. The control circuit 109 detects the end of the filtration process of the environmental water, for example, when all of the environmental water contained in the sample water bottle 300 has been filtered.

[0038] For example, the control circuit 109 measures a decrease in the load on the main pump 104 to detect the end of the filtration process and thereby detect the end of the filtration process of the environmental water. Specifically, the control circuit 109 is configured to input the real-time current consumption value of the main pump 104. The control circuit 109 compares the current consumption value of the main pump 104 with a preset threshold value and detects a decrease in the load of the main pump 104 if the current consumption value is equal to or less than the threshold value. A state in which the load on the main pump 104 is decreased means that the main pump 104 is pushing out gases such as air instead of environmental water. The control circuit 109 determines that the filtration process of the environmental water is completed if the decrease in the load on the main pump 104 continues for a preset length of time. This state means that all of the environmental water contained in the sample water bottle 300 has been pushed out by the main pump 104. This state also means that most of the environmental water in the filter unit 103 has been discharged and replaced with gases such as air.

[0039] When the sampling device 1 is used on a ship that is moving and experiencing fluctuations in the water surface, the supply to the main pump 104 repeatedly changes from liquid to gas to liquid in the final stage of filtration. Therefore, the above-mentioned preset length for determining that the filtration process of the environmental water has ended must take this into consideration.

[0040] The filtration unit 100 may also include a pressure sensor 111 that detects the pressure of the liquid in the pipeline (liquid delivery pressure), and the control circuit 109 may perform control using the pressure detected by the pressure sensor 111. A conventional pressure sensor 111 may be used. For example, as shown in FIG. 1, the pressure sensor 111 detects the pressure of the liquid flowing into the filter 102 in real time and notifies the control circuit 109 of the detected pressure value. If the pressure detected by the pressure sensor 111 exceeds a preset pressure, the control circuit 109 stops the operation of the main pump 104 until the pressure value falls below a preset pressure for restarting the pump.

[0041] When the filtration process of the environmental water is completed, the control circuit 109 closes the valve 105 and controls the supply of the fixing reagent. When supplying the fixing reagent, the control circuit 109 operates the sub-pump 108. As described above, a portion of the fixing reagent passes through the filter 102 and is discharged from the filtration unit 100. When the fixing reagent is discharged from the filtration unit 100, the control circuit 109 controls the valve 106 to open, but may also control the valve 106 to close before that. In this case, the piping for discharging the filtered environmental water and fixing reagent from the filtration unit 100 may be flexible and have a variable volume, as described below. Conventional flexible piping can be used.

[0042] The hydrophilic filters used in conventional cartridge filters have the property of being difficult to pass gas through in the presence of liquid (preferentially passing liquid). Therefore, when a fixing reagent is supplied to the filter unit 103, which has been purged with gas such as air after filtering environmental water as shown in FIG. 4(a), the fixing reagent 400 flows into the filter unit 103 as shown in FIG. 4(b). As shown in FIG. 4(c), if the fixing reagent 400 that has passed through the filter 102 is immediately discharged, gas remains within the filter unit 103, and the filter unit 103 cannot be completely filled with the fixing reagent 400. As a result, there is a risk that the fixing reagent 400 will not be able to completely fix the environmental DNA remaining in the filter 102.

[0043] When the control circuit 109 controls the supply of the fixed reagent 400 to the filter unit 103, the fixed reagent 400 flows into the filter unit 103 as shown in Fig. 3(b). When the control circuit 109 starts this control, it controls the valve 106 provided after the filter unit 103 to close as shown in Fig. 3(c). When the fixed reagent 400 is introduced with the discharge side valve 106 closed, the fixed reagent 400 initially passes through preferentially, but as the pressure inside the filter unit 103 rises and exceeds a threshold, gases such as air inside the filter unit 103 also begin to pass through the filter 102.

[0044] When the gas begins to pass through the filter 102, the resistance of the gas passing through the filter 102 is much smaller than that of the fixing reagent 400, so the gas passes through preferentially. This allows the gas inside the filter unit 103 to be efficiently pushed out. As a result, as shown in Figure 3, the filter unit 103 is filled with the fixing reagent 400, and the environmental DNA remaining on the filter 102 can be properly fixed by the fixing reagent 400.

[0045] At this time, by making the piping 112 between the filter unit 103 and the valve 106, which is the piping for discharging the environmental water and the fixed reagent 400 after passing through the filter 102 from the filtration unit 100, flexible and variable in volume, the piping 112 expands and its volume increases as shown in Figure 3(c), thereby making it possible to prevent liquid from leaking from the conduit due to pressurization.

[0046] After the filter unit 103 is filled with the fixed reagent 400, the control circuit 109 controls the valve 106 to open as shown in FIG. 3(d). This allows the fixed reagent 400 that has passed through the filter 102 to be immediately discharged. The timing for controlling the valve 106 to open may be, for example, the timing when a preset time has elapsed since the timing for controlling the valve to close (the timing for supplying the fixed reagent 400). Alternatively, for example, the pressure of the fixed reagent 400 supplied to the filter unit 103 may be detected by the pressure sensor 111, and the control circuit 109 may open the valve 106 in accordance with the detected pressure.

[0047] The control circuit 109 may repeatedly control the supply of the fixing reagent 400 and the opening and closing of the valve 106. This repetition allows the environmental DNA remaining in the filter 102 to be fixed by the fixing reagent 400, and the fixing reagent 400 to be discharged after passing through the filter 102 appropriately and efficiently. The control circuit 109 closes the valve 106 after the discharge of the fixing reagent 400 after passing through the filter 102 is complete. The control circuit 109 closes the valves 105 and 106 before and after the filter 102 on which the environmental DNA remains and has been fixed by the fixing reagent. Closing the valves 105 and 106 prevents subsequent contamination within the filtration unit 100. Note that the filtration unit 100 may have a configuration other than that described above to control the filtration of environmental water and the supply of the fixing reagent, as long as it is capable of filtering environmental water and supplying the fixing reagent.

[0048] When the filtration unit 100 is attached to the base unit 200, electrical wiring is connected between the filtration unit 100 and the base unit 200, and power is supplied from the base unit 200 via the electrical wiring. The power input to the filtration unit 100 operates the devices provided in the filtration unit 100.

[0049] For example, the filtration unit 100 and the base unit 200 are provided with connectors 113 and 202, respectively, for exchanging power and information. When the filtration unit 100 is attached to the base unit 200, the connectors 113 and 202 are connected, enabling the exchange of power and information between the filtration unit 100 and the base unit 200.

[0050] 2 shows only one filter 102, the filtration unit 100 may include multiple filters 102. The multiple filters 102 may each filter different environmental water to collect environmental DNA. When the filtration unit 100 includes multiple filters 102, it may also include multiple components associated with the filters 102 as needed.

[0051] The base unit 200 is a device to which the filtration unit 100 is attached and which operates the filtration unit 100. The base unit 200 has a configuration that enables the filtration unit 100 to supply a filtration and fixation reagent.

[0052] The base unit 200 includes a housing 201 to which the filtration unit 100 is attached. The housing 201 of the base unit 200 has a shape that allows the filtration unit 100 to be attached. For example, as shown in FIG. 1(c), the filtration unit 100 can be fitted into the housing 201 of the base unit 200. Note that the housing 201 of the base unit 200 may have any shape as long as the filtration unit 100 can be detachably attached thereto.

[0053] The base unit 200 is provided in a housing 201 and has a configuration for discharging or storing liquid after filtration by the filter 102 discharged from the filtration unit 100 attached to the housing 201 to the outside of the device. As this configuration, the base unit 200 has, for example, the following configuration.

[0054] The base unit 200 includes a pipe (drainage port) that is connected to a pipe (drainage line) that discharges the liquid filtered by the filter 102 in the filtration unit 100 when the filtration unit 100 is attached. The base unit 200 is configured so that a drainage bottle (tank) 301 that stores the liquid that is discharged from the filtration unit 100 after filtration by the filter 102 can be connected to the pipe. The drainage liquid discharged from the filtration unit 100 passes through the pipe of the base unit 200 and is stored in the drainage bottle 301.

[0055] The drainage bottle 301 may contain both the drainage liquid, which is the filtered environmental water, and the drainage liquid, which is the fixation reagent after passing through the filter 102. Alternatively, separate drainage bottles 301 may be provided for the drainage liquid, which is the filtered environmental water, and the drainage liquid, which is the fixation reagent after passing through the filter 102. In this case, a valve for switching the flow direction, such as a three-way valve, is provided in the piping after the filter 102, so that each drainage liquid is contained in the corresponding drainage bottle 301. This control may be performed by the control circuit 109 or the like.

[0056] The base unit 200 may be configured to store the waste liquid therein, in addition to being configured to discharge the waste liquid from the device itself as described above. For example, the base unit 200 may be configured to include the waste liquid bottle 301 described above. Note that the base unit 200 may be configured in a manner other than the above to discharge or store the liquid discharged from the filtration unit 100 and filtered by the filter 102 outside the device.

[0057] The base unit 200 may further include a sensor that detects the properties of the environmental water that has been filtered by the filter 102 and discharged from the filtration unit 100 attached to the base unit 200. For example, the base unit 200 includes a sensor 203 that detects the temperature (water temperature) and electrical conductivity of the drainage liquid passing through the piping that continues to the drainage bottle 301. The sensor 203 may also detect the salinity of the drainage liquid. The properties of the filtered environmental water detected by the sensor 203 may also be other than those described above. A conventional sensor 203 may be used as such a sensor 203.

[0058] When the filtering unit 100 is attached to the base unit 200, the sensor 203 is connected to the filtering unit 100 so as to be able to transmit information to the filtering unit 100. The sensor 203 transmits a measurement value, which is the detection result, to the filtering unit 100.

[0059] The filtering unit 100 includes a storage device that stores the detection results of the sensor 203 of the base unit 200. For example, the control circuit 109 of the filtering unit 100 includes a memory 109a as the above-mentioned storage device. The control circuit 109 of the filtering unit 100 receives the detection results of the sensor 203 input to the filtering unit 100 and stores them in the memory 109a.

[0060] By storing the above information in the filtration unit 100 and transporting the filtration unit 100, the information can be read from the memory 109a at an analysis site or the like, and the detection results of the sensor 203 can be referred to.

[0061] The base unit 200 is provided with a configuration that is provided in a housing 201 and that enables filtration by the filter 102 and supply of a fixing reagent in the filtration unit 100 attached to the housing 201. As this configuration, the base unit 200 may be provided with a configuration that operates the filtration by the filter 102 and supply of a fixing reagent. As this configuration, the base unit 200 is provided with, for example, the following configuration.

[0062] The base unit 200 includes a power supply circuit 204 that receives power from an external power source (e.g., 100V AC (alternating current)) and supplies the filtering unit 100 with power for operating the filtering unit 100. The power supply from the power supply circuit 204 to the filtering unit 100 is performed via connectors 113 and 202 of the filtering unit 100 and the base unit 200, which are connected to each other. The base unit 200 may also include a power switch 205 that turns on and off the supply of power to the filtering unit 100. The power input from the external power source to the power supply circuit 204 may also be used to operate devices (e.g., sensor 203) of the base unit 200. A conventional power supply circuit 204 may be used as the power supply circuit 204.

[0063] The base unit 200 includes switches that allow an operator to operate the filtration unit 100. These switches include, for example, a start switch 206, a stop switch 207, and a post-treatment switch 208. When each of the switches 206, 207, and 208 is pressed, a signal corresponding to the switch 206 is sent to the control circuit 109 of the filtration unit 100. The signals are supplied from each of the switches 206, 207, and 208 to the control circuit 109 via connectors 113 and 202 of the filtration unit 100 and the base unit 200, which are connected to each other.

[0064] The control circuit 109 receives the signal and performs control in accordance with the signal. The start switch 206 is a switch for causing the filter 102 to perform filtration and supply of the fixing reagent. When the start switch 206 is pressed, the control circuit 109 controls the filter 102 to automatically perform filtration and supply of the fixing reagent as described above. The stop switch 207 is a switch for stopping the filtration and supply of the fixing reagent by the filter 102. When the stop switch 207 is pressed, the control circuit 109 controls the filter 102 to stop the filtration and supply of the fixing reagent that are currently being performed. The post-processing switch 208 is a switch for performing post-processing after the filtration and supply of the fixing reagent by the filter 102. When the post-processing switch 208 is pressed, the control circuit 109 controls the post-processing to be performed. Conventional switches can be used as the switches 206, 207, and 208. Note that the configuration of the base unit 200 that enables filtration and supply of the fixing reagent by the filter 102 may be other than the above.

[0065] The base unit 200 may also have a function as a water receiver, such as a drain outlet, to accommodate water leakage from the filtration unit 100. The function of the water receiver may be the same as that of a conventional device. This eliminates the need to take separate measures to prevent water leakage, thereby reducing the costs and risks associated with collecting environmental DNA. The above is the configuration of the collection device 1 according to this embodiment.

[0066] Next, a method of using the sampling device 1 according to this embodiment and its operation during use will be described. The sampling device 1 is used at a location where environmental water is filtered to collect environmental DNA. For example, the sampling device 1 may be used at a site where environmental water is obtained, such as on land or at sea (on a ship). Before using the sampling device 1, the filtration unit 100 is attached to the base unit 200 in advance.

[0067] An operator prepares environmental water from which environmental DNA is collected. Specifically, a sample water bottle 300 containing environmental water is placed inside the bottle and connected to the filtration unit 100. When the operator presses the start switch 206 of the base unit 200, a corresponding signal is input to the control circuit 109, and the control circuit 109 controls filtration by the filter 102 and the supply of the fixing reagent in the filtration unit 100.

[0068] In response to this control, first, the environmental water contained in the sample water bottle 300 is pushed out to the filter 102 by the main pump 104. The environmental water is filtered by the filter 102, and the environmental DNA remains as a residue (filtrate). Next, the fixing reagent contained in the reagent container 107 is pushed out and supplied to the filter 102 by the sub-pump 108. The fixing reagent fixes the environmental DNA remaining in the filter 102. In addition, a portion of the fixing reagent passes through the filter 102. At this time, the valve 106 of the filter 102 may be closed as described above, and the fixing reagent may be supplied appropriately.

[0069] Once filtration by the filter 102 and supply of the fixation reagent are complete, the filtration unit 100 is removed from the base unit 200. The filtration unit 100, containing the collected environmental DNA fixed by the fixation reagent, is transported, for example, to an analysis site. At the analysis site, the environmental DNA is extracted from the filtration unit 100 and analyzed. The above is the method of use of the collection device 1 according to this embodiment and the operation during use.

[0070] In the collection device 1 according to this embodiment, the entire filtration unit 100 can be removed from the base unit 200 after filtration. Therefore, for example, the entire filtration unit 100 can be transported to an analysis location. This eliminates the need for work that carries the risk of contamination, such as cleaning the device, attaching and detaching only the filter 102 (filter unit 103), and replenishing the fixing reagent at the time of collection of environmental DNA, i.e., at the time of filtration.

[0071] Furthermore, a series of processes for collecting environmental DNA, such as filtering environmental water in the filtration unit 100 and supplying the fixing reagent, are automatically performed under the control of the control circuit 109. Therefore, environmental DNA can be collected even by workers who are not skilled in or have specialized knowledge of collecting environmental DNA. That is, with the collection device 1 according to this embodiment, even inexperienced workers can reliably and easily collect environmental DNA. Therefore, with the collection device 1 according to this embodiment, collection targets such as environmental DNA can be collected appropriately and easily. Furthermore, collection targets such as environmental DNA can be collected with high quality. Furthermore, collection of collection targets such as environmental DNA can be performed unmanned, thereby reducing labor.

[0072] The filtration unit 100 may include a pipe 112 for discharging the environmental water and fixation reagent that have passed through the filter 102, a valve 106 provided in the pipe 112, and a control circuit 109 that controls the valve 106 to open when the filter 102 filters the environmental water and close when the fixation reagent passes through the filter 102. With this configuration, as described above, it is possible to more appropriately fix the target substance to be collected, such as environmental DNA, remaining on the filter 102 with the fixation reagent. For example, even when a cartridge filter such as Sterivex is used as described above, gases such as air can be efficiently discharged from the filter unit 103, and the filter unit 103 can be reliably filled with the fixation reagent.

[0073] In this case, the piping 112 may be flexible and have a variable volume. This configuration allows the collection target, such as environmental DNA, remaining on the filter 102 to be more appropriately fixed by the fixing reagent. However, the piping 112 does not necessarily have to have the above configuration. Furthermore, the above configuration for supplying the fixing reagent to the filter 102 does not necessarily have to be provided in the filtration unit 100. Furthermore, the above configuration for supplying the fixing reagent to the filter 102 does not necessarily have to be based on the collection device 1 of this embodiment, and may be configured for supplying a fixing reagent to fix residues to the filter 102 after filtration.

[0074] The base unit 200 may include a sensor 203 (for example, in this embodiment, a sensor 203 for detecting temperature (water temperature) and electrical conductivity) that detects the properties of the liquid that has been filtered by the filter and discharged from the filtration unit 100 attached to the base unit 200. With this configuration, it is possible to obtain information indicating the properties of the filtered liquid in addition to collecting the environmental DNA and other collection targets.

[0075] The filtration unit 100 may include a storage device (for example, memory 109a of the control circuit 109 in this embodiment) that stores the detection results of the sensor 203. With this configuration, the filtration unit 100 stores information indicating the collected collection object and the properties of the liquid after filtration, thereby improving convenience. For example, at the analysis location to which the filtration unit 100 is transported, both the collected environmental DNA and information indicating the properties of the environmental water from which the environmental DNA was collected can be used. However, the storage device that stores the detection results of the sensor 203 and the sensor 203 do not necessarily need to be included in the collection device 1.

[0076] The base unit 200 may be provided with a configuration for operating the filtration and supply of the fixation reagent and for filtering by the filter 102. With this configuration, the collection target, such as environmental DNA, can be collected by operating the configuration provided in the base unit 200. However, the configuration provided in the base unit 200 for filtering by the filter 102 and for supplying the fixation reagent does not necessarily have to be a configuration for operating the filtration and supply.

[0077] Next, examples according to this embodiment will be described. In Example 1, a test was conducted using a collection device including a filtration unit with one filter unit. The collection device was installed in a room on board a regular shipping vessel. Seawater collected from the ship's seawater supply line was used as a sample, and 5 L of seawater was filtered using a membrane filter unit (Sterivex GP) with a pore size of 0.45 μm to collect a sample for analysis of environmental DNA contained in environmental water. The liquid delivery conditions were set to a flow rate that could process 5 L in approximately 20 minutes. As a result, filtration capture and fixation of environmental DNA were successfully performed. The filtration unit removed from the base unit was stored in a refrigerator and transported to the laboratory by refrigerated delivery service.

[0078] In Example 2, a test was conducted using a collection device including a filtration unit with four filter units. The collection device was installed in a room on board a regular shipping vessel. Seawater collected from the ship's seawater supply line was used as a sample. 20 L of seawater was filtered using a membrane filter unit (Sterivex GP) with a pore size of 0.45 μm to collect environmental DNA contained in the environmental water. The flow rate was set to a rate that could process 20 L in approximately one hour. When multiple filters were used, all filters were used in parallel during sample filtration. After filtration, air replacement and the introduction of fixation reagent were performed in sequence on each filter unit. As a result, filtration and fixation of environmental DNA were successfully performed. The filtration unit was removed from the base unit, stored in a refrigerator, and transported to the laboratory by refrigerated courier.

[0079] The collection device and filtration unit of the present disclosure have the following configuration. [1] A collection device including a filtration unit and a base unit to which the filtration unit can be detachably attached, The filtration unit comprises: a filter for filtering a liquid containing the object to be collected; and supplying a fixation reagent for fixing the sampled object remaining in the filter through which the liquid has been filtered, The base unit a housing in which the filtration unit is mounted; a configuration provided in the housing, which discharges the liquid filtered by the filter discharged from the filtration unit attached to the housing to the outside of the device or stores the liquid therein; a configuration provided in the housing that enables filtration by the filter and supply of the fixed reagent in the filtration unit attached to the housing. [2] The filtration unit comprises: a pipe for discharging the liquid and the fixing reagent that have passed through the filter; a valve provided in the piping; a control device that controls the valve to open when the filter is filtering the liquid and to close when the immobilization reagent is passing through the filter; The collection device according to [1], further comprising: [3] The collection device according to [2], wherein the piping is flexible and has a variable volume. [4] The base unit The collection device according to any one of [1] to [3], further comprising a sensor for detecting the properties of the liquid discharged from the filtration unit attached to the collection device after filtration by the filter. [5] The filtration unit comprises: The collection device described in [4] further comprises a memory device that stores the detection results by the sensor. [6] The base unit The collecting device according to any one of [1] to [5], further comprising a configuration for operating the filtration and supply of the fixing reagent as a configuration for enabling the filtration by the filter and the supply of the fixing reagent. [7] A filtration unit included in the collection device described in any one of [1] to [5]. [Explanation of symbols]

[0080] 1...collection device, 100...filtration unit, 101...housing, 102...filter, 103...filter unit, 104...main pump, 105...valve, 106...valve, 107...reagent container, 108...auxiliary pump, 109...control circuit, 109a...memory, 110...motor driver, 111...pressure sensor, 112...piping, 113...connector, 200...base unit, 201...housing, 202...connector, 203...sensor, 204...power circuit, 205...power switch, 206...start switch, 207...stop switch, 208...post-treatment switch, 300...sample water bottle, 301...drainage bottle.

Claims

1. A collection device including a filtration unit and a base unit to which the filtration unit can be detachably attached, The filtration unit comprises: a filter for filtering a liquid containing the object to be collected; and supplying a fixation reagent for fixing the sampled object remaining in the filter through which the liquid has been filtered, The base unit a housing in which the filtration unit is mounted; a configuration provided in the housing, which discharges the liquid filtered by the filter discharged from the filtration unit attached to the housing to the outside of the device or stores the liquid therein; a configuration provided in the housing that enables filtration by the filter and supply of the fixed reagent in the filtration unit attached to the housing.

2. The filtration unit comprises: a pipe for discharging the liquid and the fixing reagent that have passed through the filter; a valve provided in the piping; a control device that controls the valve to open when the filter is filtering the liquid and to close when the immobilization reagent is passing through the filter; The collection device of claim 1 further comprising:

3. 3. The collection device according to claim 2, wherein the piping is flexible and has a variable volume.

4. The base unit 3. The collection device according to claim 1, further comprising a sensor for detecting the properties of the liquid discharged from the filtration unit attached to the collection device after filtration by the filter.

5. The filtration unit comprises: The sampling device according to claim 4 , further comprising a storage device for storing the detection results of the sensor.

6. The base unit The collection device according to claim 1 or 2, further comprising a configuration for operating the filtration and supply of the fixing reagent, as a configuration for enabling the filtration by the filter and the supply of the fixing reagent.

7. A filtration unit included in the collection device according to claim 1 or 2.

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