CN115725390A - System for full-automatic sectional type of normal position is enriched water environment DNA - Google Patents

Abstract

The invention relates to an in-situ full-automatic sectional type water environment DNA enrichment system which comprises a water sample suction head, a primary separation device, a secondary separation device, a tertiary separation device, a DNA enrichment device, a circulating water container, a plankton sample collection device and a central controller. The system can obtain four biological indexes which are crucial to water environment evaluation in one water sample treatment: including water-sensitive zooplankton, phytoplankton, planktonic bacteria, and free DNA (the major component is macrophyte DNA). The system can be arranged at a preselected water area monitoring point, so that a water sample is taken regularly for enriching the environmental DNA within one year or even longer, the volume of the environmental DNA sample obtained by enrichment is small, the environmental DNA sample is convenient to carry, and the environmental DNA sample can be easily transferred to a laboratory for relevant detection and analysis. Therefore, the biodiversity condition in the target water area can be monitored for a long time, and the biodiversity condition can be taken as one of the water environment monitoring factors to be brought into the water ecology evaluation system.

Description

A system for in-situ fully automatic segmented enrichment of environmental DNA in water

technical field

The invention relates to the field of water ecology research and monitoring, and more particularly relates to a system that can be used for enriching water environment DNA.

Background technique

Water ecological health diagnosis is an important part of environmental protection, governance and restoration. Aquatic organisms are an important index to evaluate the water environment. Due to the uneven distribution of plankton in the water, especially the larger zooplankton, even if a large volume of water samples is collected for plankton analysis, it is still not enough to make a complete statistics of the plankton in the water body. In order to make up for this problem, environmental DNA (eDNA) in water samples is often analyzed in water environment monitoring. Environmental DNA in water includes free DNA and in vivo DNA in plankton. The detection and analysis of environmental DNA in water bodies can be used to indicate the composition of species in water bodies and characterize the health of aquatic ecosystems.

At present, environmental DNA is often obtained by collecting plankton in the water body, and then cracking and extracting DNA. However, this method often ignores the free DNA composition in the environment itself. This part is mainly used for monitoring and evaluating the diversity of fish in water areas. . DNA enrichment materials can be used to enrich free DNA in water, but the concentration of free DNA in water is very low. Likewise, existing devices for DNA enrichment in aquatic environments do not work well for collecting lower-abundance plankton. To obtain this part of DNA and plankton, a large number of water samples need to be enriched, but it is inconvenient to transport large volumes of water samples back to the laboratory for enrichment, and pollution occurs during transportation. Further, if the water used for free DNA enrichment contains too many particles (such as plankton), the enrichment effect and service life of the DNA enrichment device will be affected.

Therefore, it is necessary to construct an in-situ, fully automatic and segmented enrichment system for environmental DNA in water.

Contents of the invention

In order to solve the above problems, the present invention provides an in-situ fully automatic segmented enrichment system for water environment DNA, including a water sample tip, a primary separation device, a secondary separation device, a tertiary separation device, a DNA enrichment device, Circulating water container and plankton sample collection device, and central controller;

The water outlet of the water sample tip is connected to a water inlet of the first-level separation device, and the filtrate outlet of the first-level separation device is connected to the water inlet of the second-level separation device. The filtrate outlet is connected to the water inlet of the three-stage separation device, the filtrate outlet of the three-stage separation device is connected to the water inlet of the DNA enrichment device, and a water outlet of the DNA enrichment device is connected to the circulating water container The water inlet is connected, and a water outlet of the circulating water container is connected with a water inlet of the first-stage separation device;

The central controller is in communication connection with the water sample suction head, primary separation device, secondary separation device, tertiary separation device, DNA enrichment device, circulating water container and plankton sample collection device.

Through the system of the present invention, a large amount of water samples can be concentrated and enriched in situ into a very small volume of plankton concentrate and free DNA enrichment solution, both of which can be conveniently transported to a qualified laboratory for further analysis, thereby Obtaining complete environmental DNA information and plankton classification information is an excellent water environment monitoring tool. Extraction of cell-free DNA through large-volume enrichment avoids the potential impact of fish capture on the ecosystem, and provides a non-destructive monitoring method for the diagnosis of large-scale aquatic biodiversity.

The system of the present invention can be arranged at pre-selected water area monitoring points, so that water samples can be taken regularly for enrichment of environmental DNA in a year or even longer, and the environmental DNA samples obtained by enrichment are small and easy to carry, and can It is easy to transfer the environmental DNA sample to the laboratory for relevant detection and analysis after each or several enrichments are completed. In this way, the long-term monitoring of the biodiversity in the target waters can be realized, and it can be included in the water ecological evaluation system as one of the factors of the water environment.

In a specific embodiment, the primary separation device includes a housing and a filter assembly;

The housing is made of watertight material, wrapping the filter assembly in the inner space;

The filter assembly includes a cylindrical filter area and a motor, the motor is arranged on the inner wall of the top of the housing and connected to the outer wall of the top of the filter part, the rotation of the motor can drive the filter area to rotate, The side wall of the filter area is set as a screen structure;

A water inlet is provided in the center of the top of the filter area, passing through the housing, and connecting with the water sample suction head and the circulating water container through pipes;

The bottom of the filter area is provided with a concave enrichment area, and the bottom of the enrichment area is provided with a plankton concentrate outlet, and the plankton concentrate outlet passes through the shell and connects with the plankton sample through a pipeline. collection device connection;

The bottom of the housing is also provided with a filtrate outlet, which is connected to the water inlet of the secondary separation device through a pipeline. The pore size of the sidewall screen structure of the filter area is set to 20-64 μm, wherein 64 μm is the size of a commonly used plankton net (No. 25 net) for water quality aquatic life monitoring, and most of the plankton in normal water bodies are contained in the in this fraction. For water bodies with low particle content, the pore size can be increased to 20 μm, so as to give full play to the high separation performance of the cross-flow field and reduce the second-stage separation pressure. Among them, 64 μm is the size of plankton net (No. 25 net) commonly used in water quality aquatic life monitoring. The separation principle of this stage adopts cross-flow field separation with high performance. For water bodies with low particle content, the pore size can be increased to 20 μm, so as to fully exert the cross-flow field separation performance and reduce the second-stage separation pressure.

In a specific embodiment, both the secondary separation device and the tertiary separation device are equipped with an ultrafiltration device in a backwash section, and the filter pore size of the secondary separation device is larger than that of the tertiary separation device. Preferably, the filter pore size of the secondary separation device is 0.7-1.2 μm, and the filter pore size of the tertiary separation device is 0.2 μm. Among them, 0.7 μm and 1.2 μm respectively correspond to the pore diameters of the most commonly used filter membranes for water quality testing: GF/F and GF/C glass fiber membranes.

Since the filter pore size of the three-stage separation device is 0.2 μm, which is the same as the filter membrane pore size of the current filtration method for enriching bacteria, the system can intercept zooplankton in water samples by integrating the first-stage and second-stage enrichment samples , phytoplankton and phytoplankton bacteria, without missing genetic information. In order to ensure the operating efficiency of the system, the system is equipped with a primary separation device upstream of the secondary separation device and the tertiary separation device. The filter aperture of the separation device is 20-64 μm, which intercepts and collects zooplankton and phytoplankton larger than this size , thus ensuring the efficient operation of the downstream secondary separation device and tertiary separation device.

In a specific embodiment, the plankton sample collection device includes three plankton sample collection bottles, and each of the three plankton sample collection bottles is respectively connected with the primary separation device, the secondary separation device and the tertiary separation device .

We collected the plankton intercepted by the three separation devices separately. The primary separation device intercepted all the plankton larger than 20-64 μm, of which 64 μm is the size of the plankton net (No. 25 net) commonly used for water quality aquatic life monitoring. Most of the plankton are contained in this fraction. Some zooplankton retained by the primary separation device can be used as sensitive indicators for water quality evaluation. For example, Daphnia magna, this type of zooplankton is more sensitive to water quality, therefore, the plankton separated by the primary separation device can be used as an early warning indicator of water quality. In addition, the setting of the first separation device not only provides a grading effect on the plankton in the water, but also retains most of the plankton for the subsequent two-stage ultrafiltration classification, preventing the ultrafiltration membrane of the latter two-stage separation device from being blocked , to ensure the efficient operation of the last two-stage separation device and the entire system.

The size of the plankton trapped by the secondary separation device is larger than 0.7-1.2 μm and smaller than the first-level retention aperture (20-64 μm). Among them, 0.7 μm and 1.2 μm correspond to the pore diameters of commonly used filter membranes for water quality testing: GF/F and GF/C glass fiber membranes, respectively. This part of phytoplankton is mainly (ultra) microphytoplankton, which contains some phytoplankton that are small, fast-growing, and easy to disperse. Many of these phytoplankton can cause blooms. Therefore, the phytoplankton intercepted by the secondary separation Biology provides an important reference for the possibility of future algal blooms in water bodies and the types of algal blooms.

The plankton retained by the tertiary separation device is mainly some bacteria and may include some nanophytes. Bacteria are more sensitive to the content of organic matter in the water. If the content of organic matter in the water is too high, the bacteria will multiply in large numbers, which may cause the water quality to become black and smelly, forming black and smelly water. Therefore, the plankton intercepted by the three-stage separation device can be used to assist in the evaluation of organic matter content in water and as an early warning indicator of black and odorous water.

Extraction of cell-free DNA through large-volume enrichment avoids the potential impact of fish capture on the ecosystem, and provides a non-destructive monitoring method for the diagnosis of large-scale aquatic biodiversity.

Through the above arrangement, we can obtain four biological indicators that are crucial to the evaluation of the water environment in one water sample treatment: including zooplankton sensitive to water quality, phytoplankton, bacteria sensitive to organic matter, and free DNA (the main component is macroaquatic DNA). Since these four biological indicators are collected separately, the other items will not be diluted due to the high abundance of one of them, which better reflects the ecological status of the water environment and provides a basis for water environment monitoring and early warning. Important reference.

In a specific embodiment, the DNA enrichment device includes a DNA enrichment tube, an eluent storage container, a DNA sample collection bottle and a balance liquid storage container, the filtrate outlet of the three-stage separation device, the eluent Both the storage container and the balance liquid storage container are connected to the water inlet of the DNA enrichment tube, and the water outlet of the DNA enrichment tube is connected to the DNA sample collection bottle and the circulating water container.

In a specific embodiment, the DNA enrichment device includes multiple DNA enrichment tubes.

In a specific embodiment, the water inlet of the water sample tip is provided with a screen with a pore size of 3mm. Among the four major types of zooplankton, copepods are the largest, generally up to 3mm. Using a 3mm aperture will not affect the enrichment of larger plankton on the one hand, and on the other hand, it can prevent large objects from entering the system and affect the operation of the system.

In a specific embodiment, the water sample tip is provided with a detector for detecting cell density, and the detector is communicatively connected with the central controller. When the cell density in the water is detected to be too high, the water sample suction and processing are stopped to protect the system from damage.

Description of drawings

The structural schematic diagram of the system of Fig. 1 embodiment 1.

FIG. 2 is a schematic structural view of the primary separation device of the system of Example 1. FIG.

Fig. 3 is a schematic structural diagram of a DNA enrichment device in one embodiment of the system of the present invention.

FIG. 4 is a schematic structural diagram of the system of Embodiment 2.

5 is a schematic structural diagram of the DNA enrichment device in Example 2.

Fig. 6 is a schematic structural diagram of a water sample tip with an anti-blocking structure, and the water sample tip is in a normal working state of absorbing water samples.

Fig. 7 is a structural schematic diagram of a water sample tip with an anti-blocking structure. At this time, the water sample tip is in the state where the filter screen is blocked and the ultrasonic generator is working.

The names of the components corresponding to the numbers in the figure are as follows: 1. Primary separation device, 11. Shell, 11. Filtrate outlet, 12. Filter assembly, 121. Filter area, 122. Motor, 1211. Water inlet, 1212. Rich Concentration area, 1213, plankton concentrate outlet, 2, secondary separation device, 21, secondary ultrafiltrate outlet, 22, secondary backwash liquid outlet, 3, tertiary separation device, 31, tertiary ultrafiltrate Outlet, 32, three-stage backwash liquid outlet, 4, DNA enrichment device, 41, DNA enrichment tube, 411, DNA enrichment filler, 42, eluent storage container, 43, DNA sample collection bottle, 44, balance Liquid storage container, 5, circulating water container, 6, plankton sample collecting device, 61, the first plankton collecting bottle, 62, the second plankton collecting bottle, 63, the third plankton collecting bottle, 7, water sample suction Head, 70, suction head main body, 71, cell density monitoring device, 72, 10mm aperture filter screen, 73, 3mm aperture filter screen, 74, spring telescopic column, 75, baffle plate, 76, ultrasonic generator, 761, ultrasonic generation controller control switch.

Detailed ways

The principles and features of the present invention are described below in conjunction with the accompanying drawings, and the examples given are only used to explain the present invention, and are not intended to limit the scope of the present invention.

Example 1

As shown in Figure 1, the system of this embodiment includes a water sample tip 7, a primary separation device 1, a secondary separation device 2, a tertiary separation device 3, a DNA enrichment device 4, a circulating water container 5 and a plankton sample Collecting device 6, and central controller.

The water outlet of the water sample tip 7 is connected to a water inlet of the first-level separation device 1, the filtrate outlet of the first-level separation device 1 is connected to the water inlet of the second-level separation device 2, and the filtrate outlet of the second-level separation device 3 is connected to the third-level separation device. The water inlet of the separation device 3 is connected, the filtrate outlet of the three-stage separation device 3 is connected with the water inlet of the DNA enrichment device 4, a water outlet of the DNA enrichment device 4 is connected with the water inlet of the circulating water container 5, and the water outlet of the circulating water container 5 A water outlet is connected with a water inlet of the primary separation device 1 .

The water inlet of the water sample suction head 7 is provided with a stainless steel mesh screen with an aperture of more than 3 mm. Among the four major types of zooplankton, copepods are the largest, generally up to 3 mm. Using a 3 mm aperture does not affect the enrichment of larger plankton on the one hand. On the other hand, it can prevent large objects from entering the system and affecting the operation of the system.

As shown in FIG. 2 , the primary separation device 1 includes a housing 11 and a filter assembly 12 . The housing 11 is made of a watertight material and contains the filter assembly 12 in the inner space. The filter assembly 12 includes a cylindrical filter area 121 and a motor 122. The motor 122 is arranged on the inner wall of the top of the housing 11 and connected to the outer wall of the top of the filter area 121. The rotation of the motor 122 can drive the filter area 121 to rotate. A mesh structure with a pore size of 20-64 μm is provided on the side wall of the filter area 121 , and a concave enrichment area 1212 is provided at the bottom of the filter area 121 , and the enrichment area 1212 has a volume of 5-50 mL. A water inlet 1211 is provided at the center of the top of the filter area 121 , passes through the housing 11 , and is respectively connected to the water sample suction head 7 and the circulating water container 5 through pipes. At the bottom of the enrichment area 1212, there is an outlet 1213 for the plankton concentrate, and the outlet 1213 for the plankton concentrate passes through the housing 11 and is connected to the plankton sample collection device 6 through a pipeline. A filtrate outlet 111 is also provided at the bottom of the housing 11 , and the filtrate outlet 111 is connected to the water inlet of the secondary separation device 2 through a pipe.

Both the secondary separation device 2 and the tertiary separation device 3 are ultrafiltration devices with backwashing parts, the difference is that the filter membrane pore size of the secondary separation device 2 is set to 0.7-1.2 μm, and the filter membrane of the tertiary separation device 3 is The membrane pore size was set at 0.2 μm.

The secondary separation device 2 is provided with a secondary ultrafiltrate outlet 21 and a secondary backwash liquid outlet 22, the secondary ultrafiltrate outlet 21 is connected to the water inlet of the tertiary separation device through a pipeline, and the secondary backwash liquid outlet 22 passes through The pipeline is connected with the plankton sample collection device 6 .

The three-stage separation device 3 is provided with a three-stage ultrafiltrate outlet 31 and a three-stage backwash liquid outlet 32, the three-stage ultrafiltrate outlet 31 is connected with the water inlet of the DNA enrichment device 4 through a pipeline, and the three-stage backwash liquid outlet 32 Connect with plankton sample collection device 6 through pipeline.

As shown in FIG. 3 , the DNA enrichment device 4 includes a DNA enrichment tube 41 , an eluent storage container 42 , a DNA sample collection bottle 43 and a balance liquid storage container 44 . The DNA enrichment tube 41 is equipped with a DNA enrichment filler 411 . The filtrate water outlet 111 is connected with a water inlet of the DNA enrichment pipe 41 . Both the eluent storage container 42 and the balance liquid storage container 44 are connected to a water inlet of the DNA enrichment tube 41 , and the DNA sample collection bottle 43 is connected to a water outlet of the DNA enrichment tube 41 .

A water outlet of the DNA enrichment pipe 41 is connected to the circulating water container 5, and the treated water is pumped into the circulating water container 5 for temporary storage by a pump. A water outlet of the circulating water container 5 is connected with the water inlet 1211 of the primary separation device 1 to supply water to the primary separation device 1 .

All the above water inlets, water outlets, waste liquid outlets, etc. are equipped with valves to control the opening and closing where necessary. All valves and pumps are electrically connected to the central controller, and the working status of the valves and pumps is controlled by the central controller.

When in use, the water sample suction head 7 sucks the water sample and feeds it into the filter part 121 of the primary separation device 1. During the feeding process, the motor 122 drives the filter area 121 to rotate to form a cross flow field and provide centrifugal force to make the filter area 121 rotate. The water sample passes through the micropores on the side wall of the filter area 121, and the separated plankton flows out from the plankton concentrated solution outlet 1213 and enters the plankton collecting device 6, and the obtained primary filtrate flows out from the filtrate outlet 111 of the housing, into the secondary separation device 2. The primary filtrate is further filtered in the secondary separation device 2, and the separated plankton flows out from the secondary backwash liquid outlet 22 and enters the plankton collection device 6, and the secondary filtrate obtained flows out from the secondary filtrate outlet 21, into the three-stage separation device 3. The secondary filtrate is further filtered in the tertiary separation device 3, and the separated plankton flows out from the tertiary backwash liquid outlet 32, enters in the plankton collecting device 6, and the obtained tertiary filtrate flows out from the tertiary filtrate outlet 31, into the DNA enrichment device 4. After the tertiary filtrate passes through the DNA enrichment device 4 , the DNA in the water is adsorbed on the DNA enrichment filler 411 . The treated water flows out through a water outlet of the DNA enrichment pipe 41 and is temporarily stored in the circulating water container 5 . After the water sample treatment is completed, part of the water stored in the circulating water container 5 can be supplied to the primary separation device 1 to wash the primary separation device 1, so that the primary separation device 1 can be recycled. The balance liquid storage container 44 in the DNA enrichment device 4 supplies the balance liquid to the DNA enrichment tube to restore the DNA adsorption function of the DNA enrichment material 411, so that the DNA enrichment device 4 can be recycled. The secondary separation device 2 and the tertiary separation device 3 are ultrafiltration devices with backwashing parts, which have a washing function and can be recycled. Therefore, the system itself of this embodiment is a recyclable system, which can work automatically under the control of the central controller.

Through the system of this embodiment, a large number of water samples can be concentrated and enriched into a very small volume of plankton concentrate and free DNA enrichment solution, both of which can be conveniently transported to a qualified laboratory for further analysis, thereby Obtaining complete environmental DNA information and plankton classification information is an excellent water environment monitoring tool.

Since the filter pore size of the three-stage separation device is 0.2 μm, the system can intercept and collect zooplankton, phytoplankton and phytoplankton bacteria in the water sample by integrating the first, second and third stages. Ensure a more comprehensive plankton view without missing genetic information. In order to ensure the operating efficiency of the system, the system is equipped with a primary separation device upstream of the secondary separation device and the tertiary separation device. The filter aperture of the separation device is 20-64 μm, and the planktonic zooplankton and zooplankton larger than this size are intercepted and collected. Phytoplankton ensure the efficient operation of the downstream secondary separation device. Therefore, the system of this embodiment can be arranged at pre-selected water area monitoring points, so that water samples can be taken regularly for enrichment of environmental DNA, for example, within a year or even longer, and the environmental DNA samples obtained by enrichment are small and convenient. Portable, it can be easily transferred to the laboratory for relevant detection and analysis. In this way, the long-term monitoring of the biodiversity in the target waters can be realized, and it can be included in the water ecological evaluation system as one of the factors of the water environment.

Example 2

In order to make the system of the present invention work more effectively, we made improvements on the basis of Embodiment 1.

As shown in FIG. 4 , the plankton sample collection device 6 includes a first plankton collection bottle 61 , a second plankton collection bottle 62 and a third plankton collection bottle 63 . The first plankton collection bottle 61 is connected with the plankton concentrate outlet 1213 of the primary separation device 1, the second plankton collection bottle 62 is connected with the secondary backwash liquid outlet 22, and the 3rd plankton collection bottle 63 is connected with the tertiary reaction. The flushing liquid outlet 32 is connected. Also, each plankton collection bottle is pre-filled with a fixative solution to maintain the shape of the plankton that enters the collection bottle and prevent it from spoiling.

Through the above settings, we store the plankton samples intercepted by the three separation devices separately, and, due to the setting of the filter aperture, each of the three divided samples has its own index meaning.

First, the primary separation device 1 intercepts all plankton larger than 20-64 μm, wherein 64 μm is the size of a commonly used plankton net (No. 25 net) for water quality aquatic life monitoring, and most zooplankton and phytoplankton in normal water included in this fraction. Moreover, plankton of this scale are also relatively easy to observe with an optical microscope. Some zooplankton retained by the primary separation device can be used as sensitive indicators for water quality evaluation. For example, Daphnia magna, this type of zooplankton is more sensitive to water quality, therefore, the plankton separated by the primary separation device can be used as an early warning indicator of water quality. In addition, the setting of the first separation device not only provides a grading effect on the plankton in the water, but also retains most of the plankton for the subsequent two-stage ultrafiltration classification, preventing the ultrafiltration membrane of the latter two-stage separation device from being blocked , to ensure the efficient operation of the last two-stage separation device and the entire system.

The size of the plankton retained by the secondary separation device 2 is greater than 0.7-1.2 μm and smaller than the first-stage interception aperture (20-64 μm). Among them, 0.7 μm and 1.2 μm respectively correspond to the pore diameters of the most commonly used filter membranes for water quality testing: GF/F and GF/C glass fiber membranes. This part of phytoplankton is mainly (ultra)microphytoplankton, which includes some phytoplankton that are small in size, fast in reproduction, and easy to disperse. Many of these phytoplankton can cause blooms. Therefore, the intercepted by the secondary separation device 2 Plankton provides important references for the possibility of future algal blooms in water bodies and the types of algal blooms.

The plankton intercepted by the tertiary separation device 3 are mainly some bacteria and some nanophytoplankton. Bacteria are more sensitive to the content of organic matter in the water. If the content of organic matter in the water is too high, the bacteria will multiply in large numbers, which may cause the water quality to become black and smelly, forming black and smelly water. Therefore, the plankton fraction intercepted by the three-stage separation device 3 can be used to assist in evaluating the organic matter content in water and as an early warning indicator for black and odorous water.

In a specific embodiment, a phytoplankton concentration monitoring device 61 is provided on the water sample suction head 6 to monitor the phytoplankton concentration at the location where the water sample suction head 6 is located. The phytoplankton concentration monitoring device 61 communicates with the central controller, and sends phytoplankton concentration data to the central controller.

In the process of practice, we found that in some water bodies, the concentration of plankton varies greatly. When an algal bloom occurs, some dominant phytoplankton multiply in large numbers, resulting in a large amount of plankton in the water. If the device of Example 1 is used, a large amount of DNA of dominant phytoplankton enters into the total DNA collected, resulting in a large dilution of other environmental DNA in the water, which is not conducive to the statistics of the overall biodiversity in the water body.

When in use, the cell density monitoring device 71 detects the cell density at the water sample tip 7 before the water sample tip 7 starts to suck the water sample, and sends the cell density data to the central controller, and the central controller controls the cell density according to the cell density. The operating mode of the system. When the cell density is low, the system periodically draws water samples from the water for enrichment of plankton and cell-free DNA.

When algal blooms or black odorous water break out in the water area, the concentration of phytoplankton cells or bacterial cells exceeds the threshold, and the central controller stops water sampling in time to prevent the system from being damaged.

In this embodiment, the DNA enrichment device is further optimized. As shown in FIG. 5 , multiple DNA enrichment tubes 41 are provided to improve the DNA enrichment efficiency.

Example 3

The water sample suction head 7 adopts a 3mm filter screen to filter out bulky objects, but the 3mm aperture is relatively small, which is prone to blockage. Therefore, in order to solve this problem in this embodiment, an improved design is made to the water sample tip 7 . As shown in Figures 6 and 7, the water sample tip 7 of the present embodiment includes a tip body 70, which is a container with an open bottom, and the bottom opening is blocked by a 10mm aperture filter screen 72, and the top of the tip body 70 is connected to a water pipe, so that The interior of the tip body 70 can communicate with the tube pump system of the system. A 3mm filter screen 73 is fixed near the top of the suction head body 70, a spring telescopic rod 74 is fixed at the bottom of the 3mm filter screen 73, and the other end of the spring telescopic rod 74 is fixedly connected to the baffle 75, which has the same shape as the suction head main body 70. Cooperate with the bottom opening of the suction head body 70, which can just block the bottom opening of the suction head body 70. An ultrasonic generator 76 is arranged on the inner wall of the suction head main body 70, and the ultrasonic generator 76 is arranged below the 3mm aperture filter screen. The ultrasonic generator switch 761 is arranged at the bottom opening of the suction head main body 70 and above the filter screen 72 with an aperture of 10 mm.

When the spring telescopic rod 74 is set to a natural state, the baffle plate 75 is blocked, and when the water sample suction head 7 begins to absorb water samples when the pump works, the negative pressure formed by the suction head body 70 makes the spring retractable rod 74 shrink, and the baffle plate 75 is lifted. From the beginning, the water sample enters from the bottom opening of the tip main body 70, and the larger floating objects are blocked by the 10mm aperture filter screen 72, and then filtered through the 3mm aperture filter screen 73 in the tip main body 70, and then enter the system. When the 3mm aperture filter screen 73 is blocked, the negative pressure in the suction head main body 70 gradually decreases, causing the spring telescopic rod 74 to elongate under the thrust of the spring, and the baffle plate 75 descends to seal the bottom opening of the suction head main body 70 and touch The sonotrode switch 761 makes the sonotrode 76 in working order, and the sonotrode generates ultrasonic waves in the water inside the suction head main body 70, so that the foreign matter blocked on the 3mm aperture filter screen 73 is separated, and the 3mm aperture filter screen 73 is dredged, Proceed with water sample aspiration.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection of the present invention. within range.

Claims (10)

1. An in-situ full-automatic sectional type water environment DNA enrichment system is characterized by comprising a water sample suction head, a primary separation device, a secondary separation device, a tertiary separation device, a DNA enrichment device, a circulating water container, a plankton sample collection device and a central controller;

the delivery port of water sample suction head with a water inlet of one-level separator is connected, the filtrating export of one-level separator with the water inlet of second grade separator is connected, second grade separator's filtrating export with third grade separator's water inlet is connected, third grade separator's filtrating export with DNA enrichment facility water inlet is connected, a delivery port of DNA enrichment facility with circulating water container's water inlet is connected, circulating water container's a delivery port with a water inlet of one-level separator is connected, central controller with water sample suction head, one-level separator, second grade separator, third grade separator, DNA enrichment facility and circulating water container and plankton sample collection device communication connection.

2. The system of claim 1, wherein the primary separation device comprises a housing and a filter assembly;

the shell is made of a water-tight material and wraps the filter assembly in the inner space;

the filter assembly comprises a cylindrical filter area and a motor, the motor is arranged on the inner wall of the top of the shell and is connected with the outer wall of the top of the filter area, the motor can drive the filter area to rotate by rotating, and the side wall of the filter area is of a screen mesh structure;

a water inlet is formed in the center of the top of the filtering area, penetrates through the shell and is respectively connected with the water sample suction head and the circulating water container through pipelines;

a concave enrichment area is arranged at the bottom of the filtering area, a plankton concentrated solution outlet is arranged at the bottom of the enrichment area, and the plankton concentrated solution outlet penetrates through the shell and is connected with the plankton sample collecting device through a pipeline;

and a filtrate outlet is also formed in the bottom of the shell and is connected with a water inlet of the secondary separation device through a pipeline.

3. The system of claim 2, wherein the apertures of the sidewall screen structure of the filter section are set at 20-64 μm.

4. The system of claim 1, wherein the secondary separation device and the tertiary separation device are provided with an ultrafiltration device having a backwash section, and the secondary separation device has a larger filtration pore size than the tertiary separation device.

5. The system of claim 4, wherein the secondary separation device has a filter pore size of 0.7-1.2 μm.

6. The system of claim 1, wherein the planktonic sample collection device comprises three planktonic sample collection bottles, each connected to a primary separation device, a secondary separation device, and a tertiary separation device, respectively.

7. The system of claim 1, wherein the DNA enrichment device comprises a DNA enrichment tube, an eluent storage container, a DNA sample collection bottle, and a balance solution storage container, and wherein the filtrate outlet of the tertiary separation device, the eluent storage container, and the balance solution storage container are all connected to the water inlet of the DNA enrichment tube, and the water outlet of the DNA enrichment tube is connected to the DNA sample collection bottle and the circulating water container.

8. The system of claim 7, wherein the DNA enrichment device comprises a plurality of DNA enrichment tubes.

9. The system according to claim 1, wherein the water inlet of the water sampling suction head is provided with a screen with an aperture of 3mm, the water sampling suction head is provided with a detector for detecting the cell concentration, and the detector is in communication connection with the central controller.

10. The system of claim 9, wherein the water sampling tip comprises a tip body, which is an open-bottomed container, the open bottom of the water sampling tip is blocked by a 10mm pore size filter screen, and the top of the tip body is connected with a water pipe, so that the inside of the tip body can communicate with a pipe pump system of the system;

the utility model discloses a suction head, including suction head main part, 3mm filter screen, the fixed spring telescopic link in 3mm filter screen bottom, spring telescopic link's the other end and baffle fixed connection, the shape of baffle with the bottom opening cooperation of suction head main part, be provided with supersonic generator on the inner wall of suction head main part, and supersonic generator sets up the below of 3mm aperture filter screen, the supersonic generator switch sets up suction head main part bottom opening part is located 10mm aperture filter screen top.

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