Micro-nano enrichment device as well as preparation method and use method thereof

Abstract

The invention discloses a micro-nano enrichment device and a preparation method and a use method thereof, and relates to the technical field of detection equipment, the micro-nano enrichment device comprises a syringe, a cavity is formed in the syringe, an adsorption part is arranged in the cavity, a nano adsorbate is arranged in the adsorption part, a sharp nozzle is arranged on the syringe, the end part of the sharp nozzle is closed, and the nano adsorbate is arranged in the cavity. And a pushing mechanism for communicating the adsorption piece with the outside is arranged on the syringe. The rapid enrichment detection work of pollutants is achieved through mutual cooperation of the injection cylinder, the adsorption part and the pushing mechanism, the whole device is simple in structure and convenient to manufacture, the whole enrichment device can be conveniently moved to different positions and environments for rapid detection, and practicability is higher.

Description

Technical Field

[0001] The present invention relates to the technical field of nanometer detection equipment, and in particular to a micro-nano concentrator and a preparation method and a use method thereof. Background Art

[0002] Environmental water pollution caused by organic pesticides, clinical antibiotics, discarded pharmaceuticals, heavy metal emissions, and factory wastewater discharges has caused significant environmental damage, leading to serious impacts on public safety and even human health. In the context of comprehensive health, pesticide residues in fruits and vegetables are increasingly attracting widespread attention. Accurately detecting trace amounts of pesticide residues in fruits and vegetables is crucial to protecting public health. Furthermore, food poisoning and poisoning cases occur frequently, seriously impacting public safety and social security and stability.

[0003] However, the detection of trace amounts of low-abundance pollutants in various samples is a technical bottleneck that needs to be addressed urgently by the Environmental Protection Bureau, the Market Supervision Administration, and other agencies. Conventional enrichment techniques for low-abundance samples suffer from complex sample pretreatment, low reproducibility, and poor enrichment efficiency. Detecting trace pollutants in water bodies using simple detection instruments alone is difficult.

[0004] The use of nanomaterial-based enrichers can improve the enrichment effect of trace pollutants in the sample, thereby improving the detection rate of trace pollutants in the sample by conventional instruments. It will become a convenient and applicable tool for daily enrichment detection by relevant government agencies and even the general public.

[0005] For example, the announcement number CN111211034A disclosed an enrichment and desorption device for low-concentration gaseous samples on May 29, 2020, which is composed of an enrichment and desorption chamber, a nano-enrichment material, a metal filter, a heating element, a gas shut-off valve, a gas outlet and an inlet. The enrichment and desorption chamber is a hollow and closed cavity, in which a filter screen, a nano-enrichment material, and a heating element are arranged from bottom to top. The enrichment material divides the cavity into two upper and lower cavities that are not connected to each other. The nano-enrichment material is located between the filter screen and the heating element and is attached to them respectively. The above-mentioned disclosed device has a complex structure and is limited to the enrichment of gaseous samples. It cannot realize the convenient movement of the entire enricher to the liquid-phase pollutants in different environments for detection, and its practicality is relatively low. Summary of the Invention

[0006] The present invention aims to provide a convenient and fast micro-nanoconcentrator, as well as its preparation and use methods. This device achieves rapid contaminant enrichment and detection through the coordinated integration of a syringe, adsorbent, and propulsion mechanism. The overall structure is simple, making it easy to manufacture and easily move the concentrator to various locations and environments for rapid detection, enhancing its practicality.

[0007] To achieve the above-mentioned purpose, the technical solution adopted by the present invention to solve its technical problems is: a micro-nano enricher, including a syringe, a cavity is provided in the syringe, an adsorption element is provided in the cavity, a nano-adsorbent is provided in the adsorption element, a pointed nozzle is provided on the syringe, the end of the pointed nozzle is closed, and a pushing mechanism is provided on the syringe to connect the adsorption element with the outside.

[0008] The pushing mechanism includes a piston arranged in the injection cylinder, a pull rod is provided on one side of the piston, a push plate is provided on the pull rod, a tip is provided on the other side of the piston, and a connecting piece is provided on the hole wall of the injection cylinder.

[0009] The adsorbent comprises a fragile sealing layer arranged in the syringe, the fragile sealing layer is connected to the cavity wall of the inner cavity of the syringe, and the nano-adsorbent is arranged on one side of the fragile sealing layer.

[0010] The adsorbent comprises a collecting box arranged in the syringe, the nano adsorbent is arranged in the collecting box, a side tube is provided on the collecting box, the side tube extends into the sharp mouth, and the end of the side tube is closed.

[0011] A microporous filter head is provided on the pointed mouth.

[0012] A fragile layer is provided on one side of the collecting box close to the piston, and an opening is provided on one side of the collecting box close to the pointed mouth.

[0013] A microporous filter membrane is provided between the collecting box and the pointed mouth.

[0014] A method for preparing the micro-nano concentrator as described above, the preparation steps are as follows:

[0015] Step 1: Filling the adsorbent with nano-adsorbent;

[0016] Step 2: Hold the syringe and install the adsorption element into the cavity of the syringe;

[0017] Step 3: Install the pushing mechanism onto the syringe;

[0018] Step 4. Hold the syringe with the tip facing upwards, then connect the vacuum tube to the tip and pump air into the syringe until it is vacuumed.

[0019] Step 5: Use a plastic sealing machine to heat and clamp the tip, so that the tip is deformed by heat and the adsorption element is sealed in the syringe to form a micro-nano concentrator.

[0020] A method for using the micro-nano concentrator as described above comprises the following specific steps:

[0021] Step 1: Turn the micro-nano concentrator upside down so that the tip of the syringe is facing upwards. Use scissors to cut off the tip to open it to the atmosphere, and then connect the microporous filter to the tip.

[0022] Step 2: Immerse the tip of the micro-nano enricher prepared in step 1 into the liquid sample to be enriched. Pull the rod back and forth to allow the sample liquid to be absorbed into the enricher. Let it stand for 30 seconds to 5 minutes. Push the rod to move the piston to push out the liquid to complete the enrichment.

[0023] Step 3: After the enrichment is completed in the previous step, immerse the tip of the syringe into the organic elution solvent, move the pull rod to move the piston in the syringe, absorb the organic elution solvent, let it stand for 30 seconds to 5 minutes, and push out the eluent to obtain the sample to be tested.

[0024] Step 4: The test sample eluted in step 3 is subjected to enrichment detection of the target substance of the test sample in the test material of the analytical instrument.

[0025] The beneficial effects of the present invention are:

[0026] The rapid enrichment and detection of pollutants is achieved through the cooperation of the syringe, adsorption element, and pushing mechanism. The entire device has a simple structure and is easy to manufacture. The entire enricher can be easily moved to different locations and environments for rapid detection, which makes it more practical.

[0027] By arranging a microporous filter head at the tip and a microporous filter membrane in the syringe, the solution to be tested can stably enter the syringe, preventing impurities in the solution to be tested from entering the syringe, thereby ensuring the stable operation of the entire enrichment device and improving practicality.

[0028] By vacuum packaging the nano-adsorbent in a syringe, the nano-adsorbent is prevented from being contaminated by foreign matter in the outside air, thereby increasing the service life of the entire enricher. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 Schematic diagram of the structure of the first embodiment of the micro-nano enricher of the present invention.

[0030] Figure 2 Schematic diagram of the structure of the second embodiment of the micro-nano enricher of the present invention.

[0031] Figure 3 Schematic diagram of the structure of the third embodiment of the micro-nano enricher of the present invention.

[0032] In the accompanying drawings: 1-syringe, 2-pull rod, 3-piston, 4-tip, 5-push plate, 6-pointed nozzle, 7-nanoadsorbent, 8-fragile sealing layer, 9-collection box, 901-side tube, 902-fragile layer, 10-microporous filter membrane, 11-microporous filter head, 12-connecting piece. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0034] The specific implementation of the present invention is described in detail below with reference to specific embodiments.

[0035] like Figure 1-3 As shown, the micro-nano enricher includes a syringe 1, which has a cavity inside, an adsorbent in the cavity, and a nano-adsorbent 7 inside the adsorbent. The adsorbent is arranged so that the nano-adsorbent 7 is encapsulated in the syringe 1. The syringe 1 is provided with a sharp nozzle 6, the end of the sharp nozzle 6 is closed, and the sharp nozzle 6 has thermoplastic properties. The enricher needs to be cut off before use. The syringe 1 is provided with a pushing mechanism that connects the adsorbent to the outside. The pushing mechanism can not only break the adsorbent so that the nano-adsorbent 7 can be balanced with the air pressure outside the syringe 1, but also generate negative pressure in the cavity of the syringe 1, so that the external solution moves into the syringe 1 for enrichment.

[0036] During use, the end of the tip 6 is cut open, and the syringe 1 is moved so that the tip 6 extends into the solution to be tested. The pushing mechanism works to break the adsorption element in the syringe 1, and the pushing mechanism continues to work to generate negative pressure in the cavity of the syringe body 1, so that the solution to be tested moves into the syringe 1, and the target object in the solution to be tested is enriched by the nano-adsorbent 7 in the adsorption element. After the enrichment is completed, the test solution is discharged from the syringe 1. At this time, the tip 6 is moved into the organic elution solvent, and the pushing mechanism works to move the organic elution solvent into the syringe 1. The target object in the nano-adsorbent 7 dissolves into the organic elution solvent. The pushing mechanism works to discharge the organic elution solvent containing the target object from the syringe 1, and then the organic elution solvent is detected by the detection instrument. The rapid enrichment and detection of pollutants are achieved through the mutual cooperation of the syringe 1, the adsorption element, and the pushing mechanism. The entire device has a simple structure and is easy to manufacture. It is also easy to move the entire enricher to different locations and environments for rapid detection, and it is more practical.

[0037] Reference Figure 1The pushing mechanism includes a piston 3 arranged in the syringe 1, a pull rod 2 is provided on one side of the piston 3, a push plate 5 is provided on the pull rod 2, a tip 4 is provided on the other side of the piston 3, and a connecting piece 12 is provided on the hole wall of the syringe 1. When the pushing mechanism is working, the connecting piece 12 is opened to connect the syringe 1 with the outside world, and the push plate 5 is moved to make the pull rod 2 move in the syringe 1, thereby making the piston 3 at the end of the pull rod 2 move, and then the movement of the piston 3 makes the tip 4 move, and then the tip 4 moves to contact with the adsorbent, so that the tip 4 squeezes the adsorbent to break it, and the nano-adsorbent 7 in the adsorbent is connected with the outside. At this time, the connecting piece 12 is closed, thereby activating The movement of the plug 3 enables the solution outside the syringe 1 to flow into the syringe 1 through the sharp nozzle 6 and contact the nano-adsorbent 7 for enrichment. Specifically, the connecting piece 12 is used to balance the air pressure inside and outside the syringe 1, thereby ensuring that the piston 3 can move stably in the syringe 1 before the nano-adsorbent 7 is broken, thereby ensuring that the tip 4 on the piston 3 can stably achieve the crushing of the nano-adsorbent 7, and ensuring that after the connecting piece 12 is closed and the piston 3 moves, the liquid can enter the syringe 1 from the sharp nozzle 6 for enrichment. The connecting piece 12 is a vent valve. When the vent valve is open, the syringe 1 is connected to the outside world. When the vent valve is closed, the syringe 1 can only be connected to the outside world through the sharp nozzle 6.

[0038] Reference Figure 1 In the first embodiment, the adsorbent includes a fragile sealing layer 8 arranged in the syringe 1, the fragile sealing layer 8 is connected to the cavity wall of the inner cavity of the syringe 1, and the nano-adsorbent 7 is arranged on one side of the fragile sealing layer 8. During the inspection, after the pointed mouth 6 is cut open, the tip 4 squeezes the fragile sealing layer 8 as the pull rod 2 and the piston 3 move, thereby balancing the air pressure inside and outside the syringe 1, thereby facilitating the movement of the piston 3 to realize the movement of the solution on the syringe 1.

[0039] The fragile sealing layer 8 is made of a pressure-resistant material such as plastic or light aluminum foil. In this embodiment, the fragile sealing layer 8 is made of plastic and is integrally formed with the inner wall of the syringe 1. The diameter of the syringe can be adjusted according to actual needs. The fragile sealing layer 8 is arranged between the piston 3 and the tip 6. The end of the tip 6 is closed. The tip 6 and the fragile sealing layer 8 ensure that the nano-adsorbent 7 is stably placed in the syringe 1 before use, preventing the nano-adsorbent 7 from flowing out of the syringe 1 and protecting the nano-adsorbent 7.

[0040] Reference Figure 2In the second embodiment, the adsorbent includes a collecting box 9 arranged in the syringe 1, the nano-adsorbent 7 is arranged in the collecting box 9, and a side tube 901 is provided on the collecting box 9. The side tube 901 extends into the sharp nozzle 6, and the end of the side tube 901 is closed. During detection, the sharp nozzle 6 and the side tube 901 are cut apart, and the push plate 5 is moved so that the pull rod 2 drives the piston 3 to move in the syringe 1. The tip 4 on the piston 3 moves to contact the collecting box 9 until the tip 4 breaks the collecting box 9. At this time, the piston 3 moves back and forth under the drive of the pull rod 2, so that the solution outside the syringe 1 enters the collecting box 9 of the syringe 1 through the sharp nozzle 6 and the side tube 901, thereby realizing enrichment detection. The side tube 901 is used to load the nano-adsorbent 7. After the nano-adsorbent 7 is loaded into the side tube 901, the collecting box 9 is vacuumed. After the collecting box 9 is vacuumed, the side tube 901 is hot-melt sealed.

[0041] A microporous filter head 11 is provided on the pointed mouth 6. After the microporous filter head 11 is tightly connected to the pointed mouth 6, it can prevent the nano-powder from spilling out when the direction of the enricher is changed. Specifically, the microporous filter head 11 is clamped with the pointed mouth 6. The microporous filter head 11 can also prevent large particles of impurities in the solution to be detected from being blocked at the pointed mouth 6, thereby ensuring that the enrichment device can stably perform enrichment work. Specifically, the pore size of the filter pores of the microporous filter head 11 is smaller than the particle diameter of the nano-adsorbent 7, thereby preventing the nano-adsorbent 7 from flowing out of the microporous filter head 11. The pore size of the filter pores of the microporous filter head 11 is 0.1-0.5μm. In this embodiment, the pore size of the filter pores of the microporous filter head 11 is 0.22μm.

[0042] Reference Figure 3 In the third embodiment of the enricher, a fragile layer 902 is provided on the side of the collecting box 9 close to the piston 3, and an opening is provided on the side of the collecting box 9 close to the sharp nozzle 6, the opening facing the sharp nozzle 6. When in use, the sharp nozzle 6 is moved, and the push plate 5 is moved so that the pull rod 2 drives the piston 3 to move in the syringe 1. The tip 4 on the piston 3 moves to contact the fragile layer 902 on the collecting box 9 until the tip 4 breaks the fragile layer 902. At this time, the piston 3 moves back and forth under the drive of the pull rod 2, so that the solution outside the syringe 1 enters the collecting box 9 of the syringe 1 through the sharp nozzle 6, thereby realizing enrichment detection.

[0043] In this embodiment, the fragile layer 902 on the collection box 9 is made of plastic and light aluminum foil. Specifically, the fragile layer 902 is aluminum foil, the collection box 9 is made of plastic, and the aluminum foil is hot-melted onto the collection box 9.

[0044] A microporous filter membrane 10 is provided between the collection box 9 and the pointed mouth 6. The setting of the microporous filter membrane 10 makes it difficult for impurities in the solution to be detected to enter the collection box 9, thereby ensuring that the nano-adsorbent 7 is stably enriched. Specifically, the microporous filter membrane 10 is made of nylon membrane, polytetrafluoroethylene, polyethersulfone, polyvinyl fluoride, mixed cellulose ester and other materials. In this embodiment, nylon membrane is selected; the pore size of the filter pores of the microporous filter membrane 10 is smaller than the particle diameter of the nano-adsorbent 7, thereby preventing the nano-adsorbent 7 from flowing out of the microporous filter membrane 10. The pore size of the filter pores of the microporous filter membrane 10 is 0.1-0.5μm. In this embodiment, the pore size of the filter pores of the microporous filter membrane 10 is 0.22μm.

[0045] In the third embodiment, the microporous filter head 11 is replaced by a microporous filter membrane 10, thereby reducing the space occupied by the tip 6 of the entire enricher while preventing the nano-adsorbent 7 from leaking out of the syringe 1, thereby facilitating the movement of the enricher for enrichment work and reducing the number of process steps when using the enricher, thereby increasing practicality.

[0046] A method for preparing the micro-nano concentrator as described above, the preparation steps are as follows:

[0047] Step 1: Fill the adsorbent with nano-adsorbent 7;

[0048] Step 2: Hold the syringe and install the adsorption element into the cavity of the syringe 1;

[0049] Step 3: Install the pushing mechanism onto the syringe 1;

[0050] Step 4: Hold the syringe 1 with the tip 6 facing upwards, then connect the vacuum pump to the tip 6 and pump air into the vacuum;

[0051] Step 5: Use a plastic sealing machine to heat and clamp the tip 6 so that the tip 6 is deformed by heat and the adsorption element is hollowly encapsulated in the syringe 1 to form a micro-nano concentrator.

[0052] By vacuum packaging the nano-adsorbent in the syringe 1 , the nano-adsorbent is prevented from being contaminated by foreign matter in the outside air, thereby increasing the service life of the entire enricher.

[0053] Reference Figure 1 The preparation method of the first embodiment comprises the following specific steps:

[0054] Step 1: Directly inject the nano-adsorbent 7 into the syringe 1 through the tip 6;

[0055] Step 2: Point the tip 6 of the syringe 1 upwards, then connect the vacuum pump to the tip 6 and pump air to a vacuum state;

[0056] Step 3: Heating and clamping the tip 6 so that the tip 6 is deformed by heat and the nano-adsorbent 7 is vacuum-sealed in the syringe 1 . The nano-adsorbent 7 in the syringe 1 forms an adsorbent under the sealing effect of the fragile sealing layer 8 .

[0057] Step 4: insert the piston 3 into the syringe 1 to form a micro-nano enricher.

[0058] Air-sensitive nanomaterials can be encapsulated in micro-nano concentrators. Vacuum encapsulation can preserve nanomaterials for a long time to prevent them from deteriorating due to exposure to air. If the encapsulated nanomaterials are stable in the air, they can be directly thermoplastic encapsulated without vacuuming.

[0059] Reference Figure 2 The preparation method of the second embodiment comprises the following specific steps:

[0060] Step 1: inject the nano-adsorbent 7 into the collection box 9 through the side tube 901;

[0061] Step 2: Point the side tube 901 of the collection box 9 upwards, then connect a vacuum exhaust pipe to the side tube 901 and exhaust air to a vacuum state;

[0062] Step 3: Heating and clamping the side tube 901 so that the side tube 901 is deformed by heat and the nano-adsorbent 7 is vacuum-sealed in the collection box 9;

[0063] Step 4: Place the collecting box 9 in the syringe 1 until the side tube 901 of the collecting box 9 extends out of the tip 6, thereby forming an adsorption member;

[0064] Step 5: Install the pull rod 2 and the piston 3 into the syringe 1, and point the tip 4 on the piston 3 toward the collection box 9 to form a micro-nano enricher.

[0065] Reference Figure 3 The preparation method of the third embodiment comprises the following specific steps:

[0066] Step 1: inject the nano-adsorbent 7 into the collection box 9 through the side tube 901;

[0067] Step 2: Point the side tube 901 of the collection box 9 upwards, then connect a vacuum exhaust pipe to the side tube 901 and exhaust air to a vacuum state;

[0068] Step 3: Heating and clamping the side tube 901 so that the side tube 901 is deformed by heat and the nano-adsorbent 7 is vacuum-sealed in the collection box 9;

[0069] Step 4: Cut off the side tube 901 and make the end of the collection box 9 flat;

[0070] Step 5: Place the microporous filter membrane 10 in the syringe 1, and then place the collection box 9 in the syringe 1 so that the opening of the collection box 9 contacts the microporous filter membrane 10, thereby forming an adsorption member;

[0071] Step 6: Install the pull rod 2 and the piston 3 into the syringe 1, and point the tip 4 on the piston 3 toward the fragile layer 902 of the collection box 9 to form a micro-nano concentrator.

[0072] In summary, Example 1 is an integrated micro-nano enricher in which the adsorption component and the syringe 1 are integrally formed, and Examples 2 and 3 are separate micro-nano enrichers in which the adsorption component and the syringe 2 are separately formed. The micro-nano enrichers are easy and quick to prepare and have low manufacturing costs.

[0073] A method for using the micro-nano concentrator as described above comprises the following specific steps:

[0074] Step 1: Invert the micro-nano concentrator so that the tip 6 of the syringe 1 faces upward, cut off the top of the tip 6 with scissors to make it open to the atmosphere, and then connect the microporous filter head 11 to the tip 6;

[0075] Step 2: Immerse the tip 6 of the micro-nano enricher prepared in step 1 into the liquid sample to be enriched, pull the rod 2 back and forth to allow the sample liquid to be absorbed into the enricher, let it stand for 30 seconds to 5 minutes, and push the rod 2 to move the piston 3 to push out the liquid to complete the enrichment;

[0076] Step 3: After the enrichment in step 2 is completed, immerse the tip 6 of the syringe 1 in the organic elution solvent, move the pull rod 2 to move the piston 3 in the syringe 1, absorb the organic elution solvent, let it stand for 30 seconds to 5 minutes, and push out the eluent to obtain the sample to be tested.

[0077] Step 4: The test sample eluted in step 3 is subjected to enrichment detection of the target substance of the test sample in the test material of the analytical instrument.

[0078] In step 2, before the tip 6 comes into contact with the liquid sample, the connecting piece 12 is opened.

[0079] Reference Figure 1 In the first embodiment, the movement of the pull rod 2 causes the piston 3 to move, so that the tip 4 breaks the fragile sealing layer 8. After the fragile sealing layer 8 is broken, the connecting piece 12 is closed, and then the syringe 1 is moved to the tip 6 to contact the liquid sample to perform enrichment work;

[0080] Reference Figure 2 In the second embodiment, the movement of the pull rod 2 causes the piston 3 to move, so that the tip 4 breaks the collection box 9. After the collection box 9 is broken, the connecting piece 12 is closed, and then the syringe 1 is moved to the tip 6 to contact the liquid sample to perform enrichment work;

[0081] Reference Figure 3 In the third embodiment, the movement of the pull rod 2 causes the piston 3 to move, so that the tip 4 breaks the fragile layer 902 on the collection box 9. After the fragile layer 902 is broken, the connecting piece 12 is closed, and then the syringe 1 is moved to the tip 6 to contact the liquid sample for enrichment.

[0082] Specifically, in step 2, the enrichment can be repeated 1-5 times as needed to complete multiple repeated enrichments, thereby ensuring that the target in the solution to be detected can be stably enriched.

[0083] In step 3, different types of organic elution solvents are selected according to different enriched substances, and the organic elution solvent is selected from one of acetonitrile, ethyl acetate, methanol, and dichloromethane.

[0084] In step 4, the test sample eluted in step 3 is concentrated by air purge method, and then qualitatively and quantitatively analyzed by modern analytical instruments such as gas chromatography-mass spectrometry or liquid chromatography-mass spectrometry to complete the enrichment detection of the target in the sample.

[0085] Specifically, refer to Figure 1 and Figure 2 In the first and second embodiments, in step 1, the microporous filter head 11 needs to be installed on the tip 6, and referring to Figure 3 In the third embodiment, since the microporous filter membrane 10 is provided in the syringe barrel 1, there is no need to install the microporous filter head 11 on the tip 6 during use.

[0086] When preparing the above-mentioned enricher: the present micro-nano enricher can be loaded with various nanopowders; and according to the enrichment performance of the nanopowders, it can be used to enrich and analyze various test materials, including environmental water, fruit and vegetable washing liquid, blood, urine and gastric content separation liquid; according to the enrichment performance of the nanopowders, it can be used to enrich and analyze various target substances, including organic pesticides, antibiotics, sleeping pills, heavy metal ions and dyes.

[0087] When using:

[0088] To detect chlorpyrifos in the solution to be tested, a certain amount of 1000 mg / L chlorpyrifos methanol solution (mother liquor) was taken and diluted with deionized water to obtain a chlorpyrifos working solution with a concentration of 0.05-5.0 μg / L. 5 mg of "nickel@silica-graphene" nanocomposite tube powder was encapsulated into the Figure 1 Use the concentrator to slowly pump chlorpyrifos solutions of varying concentrations back and forth 5-10 times. Soak for 30-300 seconds after each pumping. After the final pumping, push out all the liquid. Then, slowly draw in 0.25-0.5 mL of acetonitrile eluent. After 2-5 minutes of evaporation, slowly push out the eluent to obtain a trace amount of enriched solution for detection.

[0089] To detect the presence of fenitrothion in the solution to be tested, a certain amount of 1000 mg / L of fenitrothion methanol solution (mother liquor) was diluted with deionized water to obtain a fenitrothion working solution with a concentration of 0.05-5.0 μg / L. 5 mg of "nickel@silica-graphene" nanocomposite tube powder was encapsulated in Figure 2 The micro-nanoconcentrator in Collection Box 9 was used. The concentrator was used to slowly pump back and forth 5-10 times with solutions of varying fenitrothion concentrations. After each pumping, the solution was soaked for 30-300 seconds. After the final pumping, all liquid was expelled. Then, 0.25-0.5 mL of acetone eluent was slowly drawn in. After 2-5 minutes of evaporation, the eluent was slowly expelled to obtain a trace amount of enriched solution for detection.

[0090] To detect diazinon in the solution to be tested, a certain amount of diazinon methanol solution (1000 mg / L) (mother liquor) was taken and diluted with deionized water to obtain a diazinon working solution with a concentration of 0.05-5.0 μg / L. 5 mg of "nickel@silica-graphene" nanocomposite tube powder was encapsulated into Figure 3 Use the concentrator to slowly pump back and forth 5-10 times of different concentrations of diazinon solution. Soak for 30-300 seconds after each pumping. After the last pumping, push out all the liquid. Then slowly draw in 0.25-0.5mL of acetonitrile eluent. After 2-5 minutes of rest, slowly push out the eluent to obtain a trace amount of enriched solution for detection.

[0091] When testing tetracycline in the solution to be tested, a certain amount of tetracycline methanol solution (1000 mg / L) (mother liquor) is taken and dissolved with deionized water to obtain a tetracycline solution with a concentration of 10-70 mg / L. 5 mg of "nickel@ZIF-8" nanocomposite tube powder is encapsulated into Figure 1 Use the concentrator to slowly pump tetracycline solutions of varying concentrations back and forth 5-10 times, soaking for 30-120 seconds after each pumping. After the final pumping, push out all the liquid. Then, slowly draw in 0.25-0.5 mL of acetonitrile eluent. After 2-5 minutes of evaporation, slowly push out the eluent to obtain a trace tetracycline enriched solution for detection.

[0092] When testing cefixime in the solution to be tested, a certain amount of cefixime methanol solution (1000 mg / L) (mother liquor) was taken and dissolved with deionized water to obtain a cefixime solution with a concentration of 10-70 mg / L. 5 mg of "nickel@ZIF-8" nanocomposite tube powder was encapsulated into Figure 1 The micro-nanoconcentrator was used to slowly pump cefixime solutions of varying concentrations back and forth 5-10 times. After each pumping, the solution was soaked for 30-120 seconds. After the final pumping, all liquid was pushed out. Then, 0.25-0.5 mL of acetonitrile or other eluent was slowly drawn in. After 2-5 minutes of simmering, the eluent was slowly pushed out to obtain a trace cefixime enriched solution for detection.

[0093] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A micro-nano concentrator, characterized in that: The invention comprises a syringe (1), wherein a cavity is provided in the syringe (1), an adsorption member is provided in the cavity, a nano-adsorbent (7) is provided in the adsorption member, a pointed nozzle (6) is provided on the syringe (1), the end of the pointed nozzle (6) is closed, and a pushing mechanism for connecting the adsorption member to the outside is provided on the syringe (1).

2. A micro-nano concentrator according to claim 1, characterized in that: The pushing mechanism comprises a piston (3) arranged in an injection barrel (1), a pull rod (2) being provided on one side of the piston (3), a push plate (5) being provided on the pull rod (2), a tip (4) being provided on the other side of the piston (3), and a connecting piece (12) being provided on the hole wall of the injection barrel (1).

3. A micro-nano concentrator according to claim 2, characterized in that: The adsorbent comprises a fragile sealing layer (8) arranged in the injection barrel (1), the fragile sealing layer (8) being connected to the cavity wall of the inner cavity of the injection barrel (1), and the nano-adsorbent (7) being arranged on one side of the fragile sealing layer (8).

4. A micro-nano concentrator according to claim 2, characterized in that: The adsorbent comprises a collection box (9) arranged in the syringe (1), the nano-adsorbent (7) is arranged in the collection box (9), and the collection box (9) is provided with a side tube (901), the side tube (901) extends into the tip (6), and the end of the side tube (901) is closed.

5. The micro-nano concentrator according to claim 4, characterized in that: The pointed mouth (6) is provided with a microporous filter head (11).

6. The micro-nano concentrator according to claim 4, characterized in that: A fragile layer (902) is provided on the side of the collecting box (9) close to the piston (3), and an opening is provided on the side of the collecting box (9) close to the nozzle (6).

7. The micro-nano concentrator according to claim 6, characterized in that: A microporous filter membrane 10 is provided between the collecting box 9 and the pointed nozzle 6 .

8. A method for preparing a micro-nano concentrator according to any one of claims 1 to 7, characterized in that: The preparation steps are as follows: Step 1: Filling the nano-adsorbent (7) into the adsorption component; Step 2: Hold the syringe (1) and install the adsorption element into the cavity of the syringe (1); Step 3: Install the pushing mechanism onto the syringe (1); Step 4: Hold the syringe (1) with the tip (6) facing upwards, then connect the vacuum pump to the tip (6) and pump air into the syringe until it is vacuumed. Step 5: Using a plastic sealing machine to heat and clamp the tip (6), so that the tip (6) is deformed by heat and the adsorption element is hollowly encapsulated in the syringe (1), thereby forming a micro-nano concentrator.

9. A method for using the micro-nano concentrator according to any one of claims 1 to 7, characterized in that: The specific steps are as follows: Step 1: Invert the micro-nano concentrator so that the tip (6) of the syringe (1) faces upward, cut off the top of the tip (6) with scissors to allow it to communicate with the atmosphere, and then connect the microporous filter head (11) to the tip (6); Step 2: Immerse the tip (6) of the micro-nano enricher prepared in step 1 into the liquid sample to be enriched, pull the rod (2) back and forth to allow the sample liquid to be absorbed into the enricher, let it stand for 30 seconds to 5 minutes, push the rod (2) to move the piston (3) to push out the liquid, and complete the enrichment; Step 3: After the enrichment in step (2) is completed, immerse the tip (6) of the syringe (1) into the organic elution solvent, move the pull rod (2) to move the piston (3) in the syringe (1), absorb the organic elution solvent, let it stand for 30 seconds to 5 minutes, and push out the eluent to obtain the sample to be tested. Step 4: The test sample eluted in step 3 is subjected to enrichment detection of the target substance of the test sample in the test material of the analytical instrument.

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