Method for forming supported liquid membrane in situ and application of supported liquid membrane in extraction system

Abstract

The invention relates to the technical field of sample pretreatment, in particular to a method for forming a supported liquid membrane in situ and application of the method in an extraction system. According to the specific technical scheme, the method comprises the following steps: (1) adding an organic membrane solvent into a receiving phase solution to obtain a receiving phase working solution; (2) adding a sample solution into a donor phase chamber of the extraction device, placing a membrane carrier material in a groove above the donor phase chamber, screwing a receiving phase chamber into the donor phase chamber in a spiral manner, and pressing the membrane carrier material; and (3) uniformly mixing the receiving phase working solution in a vortex manner, and then adding the receiving phase working solution into a receiving phase chamber, so that the organic membrane solvent is automatically migrated to the surface and pores of the membrane carrier material, and a supported liquid membrane is formed in situ. According to the invention, the experimental process of traditional supported liquid membrane liquid phase microextraction is simplified, the analysis error caused by manual operation is reduced, the analysis time cost is reduced, and the commercialization and automation development of the supported liquid membrane liquid phase microextraction technology is promoted.

Description

Technical Field

[0001] The present invention relates to the technical field of sample pretreatment, and in particular to a method for in-situ forming a supported liquid membrane and application thereof in an extraction system. Background Art

[0002] In the field of analytical chemistry, sample pretreatment is a crucial step in the analysis process due to the wide variety of samples to be tested, complex matrices, and low target content. To meet development requirements such as environmental friendliness, time-saving, and high efficiency, some miniaturized sample pretreatment technologies have received increasing attention. Among them, liquid phase microextraction technology based on supported liquid membranes has been widely used in the analysis process of various samples due to its excellent sample purification ability, good selectivity, and low organic solvent consumption. Liquid phase microextraction technology based on supported liquid membranes mainly includes three forms: liquid phase microextraction (Chinese patent CN112138428A), electromembrane extraction (Journal of Chromatography A, 2006, 1109, 183-190), and a combination of the two (Analytical Chemistry, 2015, 87, 6951-6957). Conventional devices are composed of three parts: a receiving phase, a supported liquid membrane, and a donor phase. Among them, the supported liquid membrane is formed by the organic membrane solvent being fixed in the pores of the membrane carrier material through capillary action, and is a key factor affecting the extraction performance and extraction selectivity.

[0003] At present, supported liquid membranes are mainly prepared by the following two methods: i) manually dripping or applying the organic membrane solvent on the surface of the membrane material; ii) soaking the membrane carrier material in the organic membrane solvent for a certain period of time, taking it out, and wiping off the excess membrane solvent on the surface. The above-mentioned manual preparation method of supported liquid membranes is relatively cumbersome and cannot guarantee the consistency of membrane preparation, which is not conducive to the high-throughput analysis and automation development of supported liquid membrane microextraction technology. Although a team has developed a commercial electromembrane extraction device (LCGC North America, 2020, 38, 435-439), the device still uses manual dripping of membrane solvents to prepare supported liquid membranes, which to a certain extent limits the standardization of the extraction process. In recent years, in order to meet the analysis needs of more substances, new membrane materials such as polymer inclusion membranes (Chemical Engineering Journal, 2025, 158916), electrospinning membranes (Analytical Chimica Acta, 2019, 1088, 168-177), and semi-interpenetrating network polymer support membranes (Chinese patent CN112138547A) have been reported one after another. Although these alternative membrane materials enhance the stability and extraction efficiency of the extraction system, it is still necessary to add membrane solvents or affinity reagents to the membrane carrier material before extraction to prepare a selective membrane barrier that allows the target analytes to pass through, and the membrane preparation process is still relatively cumbersome. Summary of the Invention

[0004] To address the shortcomings of the prior art, the present invention provides a method for in situ formation of a supported liquid membrane and its application in an extraction system, resolving the existing issues of cumbersome preparation, inconvenient storage, and difficulty in standardization of supported liquid membranes. The present invention directly adds a small amount of organic membrane solvent to a receiving phase solution to produce a receiving phase working solution. The supported liquid membrane is then formed in situ through the automatic diffusion of the organic membrane solvent, eliminating the need for pre-prepared supported liquid membranes. This simplifies the extraction process, significantly reduces time costs in large sample analysis, and promotes the automation and commercialization of liquid-phase microextraction technology.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0006] The present invention discloses a method for in-situ forming a supported liquid membrane, comprising the following steps:

[0007] (1) adding an organic membrane solvent to a receiving phase solution to obtain a receiving phase working solution;

[0008] (2) adding the sample solution to the donor phase chamber of the extraction device, placing the membrane carrier material in the groove above the donor phase chamber, screwing the receiving phase chamber into the donor phase chamber by a spiral manner and pressing the membrane carrier material;

[0009] (3) The receiving phase working solution is vortex-mixed and then added to the receiving phase chamber, so that the organic membrane solvent automatically migrates to the surface of the membrane support material and its pores, forming a supported liquid membrane in situ.

[0010] Preferably, in step (1), the volume ratio of the organic membrane solvent to the receiving phase solution is 2%-10%.

[0011] Preferably, in step (1), the organic membrane solvent is one or more of nitroaromatic ethers, substituted aromatic hydrocarbons, phosphates, and deep eutectic solvents.

[0012] Preferably, the nitroaromatic ethers include but are not limited to 2-nitrophenyl octyl ether and 2-nitrophenyl pentyl ether, the substituted aromatic hydrocarbons include but are not limited to 2-nitroethylbenzene and 4-nitroisopropylbenzene, the phosphates include but are not limited to di(2-ethylhexyl) phosphate and di(2-ethylhexyl) phosphite, and the deep eutectic solvents include but are not limited to 6-methylcoumarin / menthol and camphor / thymol.

[0013] Preferably, in step (1), 0.000%-0.01%, m / v, of a surfactant is added to the receiving phase working solution; the surfactant includes but is not limited to Triton X-100, hexadecyltrimethylammonium bromide, and sodium lauryl sulfate.

[0014] Preferably, in step (2), the membrane carrier material is one of polypropylene microporous membrane, polyvinylidene fluoride membrane, polymer inclusion membrane, and electrospinning membrane, but is not limited to these porous membrane materials.

[0015] Preferably, in step (3), the receiving phase working solution is vortexed for 10-60 seconds and is mixed evenly without forming a stable emulsion.

[0016] The invention discloses the application of in-situ formed supported liquid membrane in liquid phase microextraction, electromembrane extraction or a combination of the two.

[0017] Preferably, when the application is liquid phase microextraction, the steps are: adding a sample solution to the donor phase chamber, placing the membrane carrier material in the groove above the donor phase chamber, screwing it into the receiving phase chamber and adding the mixed receiving phase working solution thereto, placing the assembled extraction device on a constant temperature mixer and shaking it, so that the target in the sample solution passes through the supported liquid membrane formed in situ and enters the receiving phase working solution.

[0018] Preferably, when the application is electromembrane extraction, the process comprises the following steps:

[0019] (1) Add the sample solution to the donor phase chamber where the stainless steel electrode is inserted, place the membrane support material in the groove above the donor phase chamber, screw it into the receiving phase chamber and add the mixed receiving phase working solution, and insert the platinum wire electrode into the receiving phase working solution through the electrode fixing block;

[0020] (2) The two electrodes are connected to the positive and negative poles of a DC constant voltage power supply, respectively, and the device of step (1) is placed on a constant temperature mixer for oscillation, so that the target in the sample solution passes through the in situ formed support liquid membrane under the action of the electric field and enters the receiving phase.

[0021] Preferably, in step (2), the voltage of the DC constant voltage power supply is 2-200V, and the rotation speed of the constant temperature mixer is 500-1000rpm.

[0022] Preferably, the scope of application includes but is not limited to pre-treatment of wastewater, urine or blood.

[0023] The present invention has the following beneficial effects:

[0024] 1. Compared with existing methods for preparing supported liquid membranes, the method proposed in the present invention directly adds a small amount of organic membrane solvent to the receiving phase solution, forming the supported liquid membrane in situ during the extraction process, which simplifies the operation process and can greatly save time and costs, especially when analyzing large sample volumes.

[0025] 2. The receiving phase working solution with the addition of an organic membrane solvent in the present invention can be prepared in advance and stored for a long time, without having to worry about the storage problem of the supporting liquid membrane in the prior art, and can be easily converted into a complete set of commercial liquid phase microextraction equipment.

[0026] 3. The liquid-phase microextraction method based on in situ formation of supported liquid membrane proposed in the present invention eliminates the process of manually preparing supported liquid membrane, can form a standardized extraction process, reduces the errors caused by human operation during the experiment, has good stability and repeatability, and can meet the analysis needs of various types of samples such as biological, environmental, and food. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Schematic diagram of the electromembrane extraction device based on in-situ formation of a supported liquid membrane according to the present invention; (a) is a model diagram and a physical diagram of the components of the extraction device, (b) is a diagram showing the components of the extraction device from different angles, and (c) is a model diagram and a physical diagram of the assembled extraction device;

[0028] Figure 2 is a scanning electron microscope image of the polypropylene microporous membrane selected in Examples 1-3;

[0029] Figure 3 This is a scanning electron microscope image of the supported liquid film formed in situ in Example 2. DETAILED DESCRIPTION

[0030] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0031] Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art.

[0032] The present invention discloses a method for in-situ forming a supported liquid membrane, comprising the following steps:

[0033] (1) Adding 2%-10% (v / v) of an organic membrane solvent to a receiving phase solution, with or without adding 0.001%-0.01% (m / v) of a surfactant, to obtain a receiving phase working solution;

[0034] The organic membrane solvent is one or more of nitroaromatic ethers, substituted aromatic hydrocarbons, phosphates, and deep eutectic solvents. The surfactant includes, but is not limited to, Triton X-100, cetyltrimethylammonium bromide, and sodium lauryl sulfate. The organic membrane solvents are all insoluble or poorly soluble in water, have low volatility or non-volatility, and low viscosity, exhibiting excellent stability. The surfactants possess unique amphiphilic properties, which can reduce the interfacial tension between the organic membrane solvent and the aqueous solution, promoting diffusion and migration of the organic membrane solvent when its own migration capacity is insufficient.

[0035] Specifically: the nitroaromatic ethers include but are not limited to 2-nitrophenyl octyl ether and 2-nitrophenyl pentyl ether, the substituted aromatic hydrocarbons include but are not limited to 2-nitroethylbenzene and 4-nitroisopropylbenzene, the phosphates include but are not limited to di(2-ethylhexyl) phosphate and di(2-ethylhexyl) phosphite, and the deep eutectic solvents include but are not limited to 6-methylcoumarin / menthol and camphor / thymol.

[0036] The receiving phase solution is selected based on the extraction method's principles and the target's acidity or alkalinity. In liquid-phase microextraction, when the target is alkaline, the receiving phase solution is an acidic solution such as hydrochloric acid, formic acid, or trifluoroacetic acid; when the target is acidic, the receiving phase solution is an alkaline solution such as sodium hydroxide, ammonia buffer, or phosphate buffer. In electromembrane extraction, when the target is alkaline, the receiving phase solution is one of the aforementioned acidic solutions; when the target is acidic, the receiving phase solution is one of the aforementioned alkaline solutions.

[0037] (2) adding the sample solution to the donor phase chamber of the extraction device, placing a circular polymer membrane carrier material with a diameter of 10-16 mm in the groove above the donor phase chamber, screwing the receiving phase chamber into the donor phase chamber by spiral means and pressing the membrane carrier material;

[0038] The membrane support material is selected from the group consisting of a polypropylene microporous membrane, a polyvinylidene fluoride membrane, a polymer inclusion membrane, and an electrospun membrane. Alternatively, the membrane support material has a pore size of 0.1-0.2 μm and a thickness of 100-200 μm. The selected membrane support material exhibits excellent physical and chemical stability and a uniform pore size, effectively preventing the introduction of non-target impurities such as macromolecular substances and particulate matter during the extraction process.

[0039] The sample solution includes, but is not limited to, aqueous solutions, urine, blood, environmental samples, and food samples. In specific applications, dilution, homogenization, or other simple processing is required depending on the sample type, and the organic membrane solvent type, pH values of the receiving phase solution, and sample solution, among other conditions, are optimized based on the target substance to be measured.

[0040] (3) The receiving phase working solution is vortexed and mixed and then added to the receiving phase chamber. The receiving phase working solution is vortexed for 10-60 seconds and mixed until the organic membrane solvent automatically migrates to the surface of the membrane carrier material and its pores to form a supported liquid membrane in situ. Generally, a supported liquid membrane can be quickly formed on the membrane carrier material within 3 minutes.

[0041] The present invention also discloses the application of the in-situ formed supported liquid membrane in liquid phase microextraction, electromembrane extraction, or a combination thereof, including but not limited to pre-treatment of wastewater, urine, or blood.

[0042] When the application is liquid-phase microextraction, the steps are as follows: adding a sample solution to the donor phase chamber, placing the membrane carrier material in the groove above the donor phase chamber, screwing it into the receiving phase chamber and adding the mixed receiving phase working solution thereto, placing the assembled extraction device on a constant temperature mixer and oscillating it at a speed of 500-1000 rpm, so that the target in the sample solution passes through the supported liquid membrane formed in situ and enters the receiving phase working solution.

[0043] When the application is electromembrane extraction, the steps include:

[0044] (1) Add the sample solution to the donor phase chamber where the stainless steel electrode is inserted, place the membrane support material in the groove above the donor phase chamber, screw it into the receiving phase chamber and add the mixed receiving phase working solution, and insert the platinum wire electrode into the receiving phase working solution through the electrode fixing block;

[0045] (2) The two electrodes are connected to the positive and negative poles of a DC constant voltage power supply, respectively, wherein the voltage of the DC constant voltage power supply is 2-200 V, and the device of step (1) is placed on a constant temperature mixer and oscillated at a speed of 500-1000 rpm, so that the target in the sample solution passes through the in situ formed support liquid membrane under the action of the electric field and enters the receiving phase.

[0046] The present invention will be further described below with reference to specific embodiments.

[0047] Figure 1 Schematic diagram of an electromembrane extraction device based on in situ formation of a supported liquid membrane. The liquid phase microextraction device in Example 1 is basically the same as it, except that the bottom of the donor phase chamber is a sealed structure and no electrode is inserted. The receiving phase chamber also does not have an electrode inserted, and no voltage is applied during the extraction process.

[0048] Figure 2 This is a scanning electron microscope image of the polypropylene microporous membrane selected in Examples 1-3. It can be seen that the material has a pore structure with uniform size.

[0049] Example 1

[0050] The acidic drugs naproxen, ketoprofen, ibuprofen, flurbiprofen and diclofenac are extracted from water samples under optimized extraction conditions using the liquid phase microextraction technology based on in-situ formation of supported liquid membrane disclosed in the present invention.

[0051] The steps for in situ formation of supported liquid membrane and liquid phase microextraction are:

[0052] (1) 10 mM sodium hydroxide was used as the receiving phase solution, and 5% (v / v) 2-nitroethylbenzene was added thereto to obtain a receiving phase working solution.

[0053] (2) Add 800 μL of a 1.0 mg / L mixed solution of naproxen, ketoprofen, ibuprofen, flurbiprofen, and diclofenac (prepared in 10 mM hydrochloric acid) to the donor phase chamber as the sample solution. Place a 15 mm diameter polypropylene microporous membrane in the groove above the donor phase chamber. Screw the receiving phase chamber into place and press the polypropylene microporous membrane tightly.

[0054] (3) Vortex the receiving phase working solution for 30 seconds to mix thoroughly, then add 400 μL to the receiving phase chamber. Place the assembled extraction device on a thermomixer at 25°C and 1000 rpm. Extract for 30 minutes. Centrifuge the receiving phase working solution at 12000 rpm for 3 minutes, and analyze the supernatant by high performance liquid chromatography.

[0055] Chromatographic conditions: The chromatographic column was a C18 column (150 mm × 4.6 mm, 4 μm), the column temperature was 40°C, the mobile phase A was 0.01% (v / v) formic acid, the mobile phase B was methanol, the separation method was 75% methanol isocratic separation for 8.5 min, the flow rate was 0.6 mL / min, the injection volume was 10 μL, and the detection wavelength of the UV detector was 214 nm.

[0056] The calculated recoveries of the five drugs were: naproxen 94%, ketoprofen 99%, ibuprofen 96%, flurbiprofen 95%, and diclofenac 91%.

[0057] Example 2

[0058] The alkaline drugs haloperidol, amitriptyline, fluoxetine and sertraline in water samples are extracted under optimized extraction conditions using the electromembrane extraction technology based on in-situ formation of a supported liquid membrane.

[0059] The steps for in situ formation of supported liquid membrane and electromembrane extraction are:

[0060] (1) 10 mM hydrochloric acid was used as the receiving phase solution, to which 2% (v / v) 2-nitrophenyl octyl ether and 0.01% (w / v) hexadecyltrimethylammonium bromide were added to obtain a receiving phase working solution.

[0061] (2) 800 μL of a 1.0 mg / L mixed solution of haloperidol, amitriptyline, fluoxetine, and sertraline (prepared in 10 mM hydrochloric acid) was added to the donor phase chamber, which was inserted into the stainless steel electrode. A 15 mm diameter polypropylene microporous membrane was placed in the groove above the donor phase chamber. The receiving phase chamber was screwed in and the polypropylene microporous membrane was pressed tightly.

[0062] (3) After vortexing the receiving phase working solution for 30 seconds to mix it evenly, 400 μL was added to the receiving phase chamber. The electrode fixing block wrapped with platinum wire was clamped on the receiving phase chamber so that the platinum wire electrode was deeply immersed in the receiving phase working solution.

[0063] (4) The stainless steel electrode in the donor phase chamber is connected to the positive pole of the DC constant voltage power supply, and the platinum wire electrode in the receiving phase chamber is connected to the negative pole of the power supply. The assembled extraction device is placed on a constant temperature mixer, and the temperature is set to 25°C, the speed is 1000 rpm, and the voltage is 60 V. The power is turned on and the extraction is carried out for 20 minutes. After the extraction, the receiving phase working solution is centrifuged at 12000 rpm for 3 minutes, and the supernatant is taken for high performance liquid chromatography analysis.

[0064] Chromatographic conditions: The chromatographic column was a C18 column (150 mm × 4.6 mm, 4 μm), the column temperature was 40°C, the mobile phase A was 0.01% (v / v) formic acid, the mobile phase B was methanol, the separation method was 60% methanol isocratic separation for 8 min, the flow rate was 0.6 mL / min, the injection volume was 10 μL, and the detection wavelength of the UV detector was 214 nm.

[0065] The calculated recoveries of the four drugs were: 97% for haloperidol, 97% for amitriptyline, 91% for fluoxetine, and 96% for sertraline.

[0066] The scanning electron microscope image of the supported liquid membrane formed in situ in Example 2 is as follows: Figure 3 As shown in the figure, it can be seen that the original pore structure is evenly filled with the membrane solvent 2-nitrophenyl octyl ether, and a supported liquid membrane is successfully obtained.

[0067] Example 3

[0068] The alkaline drugs haloperidol, amitriptyline, fluoxetine and sertraline in urine are extracted under optimized extraction conditions using the electromembrane extraction technology based on in-situ formation of a supported liquid membrane.

[0069] The steps for in situ formation of supported liquid membrane and electromembrane extraction are:

[0070] (1) 10 mM hydrochloric acid was used as the receiving phase solution, to which 2% (v / v) 2-nitroethylbenzene and 0.01% (w / v) Triton X-100 were added to obtain a receiving phase working solution.

[0071] (2) Prepare a urine sample spiked with 100 ng / L of a 100 ng / L solution of a mixed stock solution of haloperidol, amitriptyline, fluoxetine, and sertraline to be tested in a healthy volunteer's urine sample. Adjust the pH to 2.0 with 1 M hydrochloric acid, then dilute the sample 1:1 (v / v) with 10 mM hydrochloric acid. Take 800 μL and add it to the donor phase chamber as the sample solution. Place a 15 mm diameter polypropylene microporous membrane in the groove above the donor phase chamber, and screw the receiving phase chamber into the chamber and press the polypropylene microporous membrane tightly.

[0072] (3) After vortexing the receiving phase working solution for 30 seconds to mix it evenly, 400 μL was added to the receiving phase chamber. The electrode fixing block wrapped with platinum wire was clamped on the receiving phase chamber so that the platinum wire electrode was deeply immersed in the receiving phase working solution.

[0073] (4) The stainless steel electrode in the donor phase chamber is connected to the positive electrode of a DC constant voltage power supply, and the platinum wire electrode in the receiving phase chamber is connected to the negative electrode of the power supply. The assembled extraction device is placed on a constant temperature mixer, and the temperature is set to 25°C, the speed is 1000 rpm, and the voltage is 6V. The extraction is carried out for 20 minutes. After the extraction, the receiving phase working solution is centrifuged at 12000 rpm for 3 minutes, and the supernatant is taken and analyzed by high performance liquid chromatography coupled to mass spectrometry.

[0074] Chromatographic conditions: The chromatographic column was a C18 column (150 mm × 4.6 mm, 4 μm), the column temperature was 40°C, the mobile phase A was 0.01% (v / v) formic acid, the mobile phase B was methanol, the separation method was 60% methanol isocratic separation for 8 min, the flow rate was 0.6 mL / min, and the injection volume was 10 μL.

[0075] Mass spectrometry conditions: Electrospray ionization was used in positive ion mode, with quantification in MRM mode. Specific detection parameters for the target compounds are shown in Table 1. The calculated recoveries of the four drugs were: 88% for haloperidol, 93% for amitriptyline, 92% for fluoxetine, and 97% for sertraline.

[0076] Table 1 Mass spectrometry detection parameters for four target compounds

[0077]

[0078] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by persons skilled in the art should fall within the scope of protection defined by the claims of the present invention.

Claims

1. A method for forming an in-situ supported liquid membrane, characterized in that: The following steps are involved: (1) adding an organic membrane solvent to a receiving phase solution to obtain a receiving phase working solution; (2) adding the sample solution to the donor phase chamber of the extraction device, placing the membrane carrier material in the groove above the donor phase chamber, screwing the receiving phase chamber into the donor phase chamber by a spiral manner and pressing the membrane carrier material; (3) The receiving phase working solution is vortex-mixed and then added to the receiving phase chamber, so that the organic membrane solvent automatically migrates to the surface of the membrane support material and its pores, forming a supported liquid membrane in situ.

2. The method for in-situ formation of a supported liquid membrane according to claim 1, wherein: In step (1), the volume ratio of the organic membrane solvent to the receiving phase solution is 2%-10%.

3. The method for in-situ formation of a supported liquid membrane according to claim 1, wherein: In step (1), the organic membrane solvent is one or more of nitroaromatic ethers, substituted aromatic hydrocarbons, phosphates, and deep eutectic solvents.

4. The method for in-situ formation of a supported liquid membrane according to claim 3, wherein: The nitro aromatic ethers include but are not limited to 2-nitrophenyl octyl ether and 2-nitrophenyl pentyl ether, the substituted aromatic hydrocarbons include but are not limited to 2-nitroethylbenzene and 4-nitroisopropylbenzene, the phosphates include but are not limited to di(2-ethylhexyl) phosphate and di(2-ethylhexyl) phosphite, and the deep eutectic solvents include but are not limited to 6-methylcoumarin / menthol and camphor / thymol.

5. The method for in-situ formation of a supported liquid membrane according to claim 1, wherein: In step (1), a surfactant (0.000%-0.01%, m / v) is added to the receiving phase solution; the surfactant includes but is not limited to Triton X-100, hexadecyltrimethylammonium bromide, and sodium lauryl sulfate.

6. The method for forming an in-situ supported liquid membrane according to claim 1, wherein: In step (2), the membrane carrier material is one of a polypropylene microporous membrane, a polyvinylidene fluoride membrane, a polymer inclusion membrane, and an electrospinning membrane.

7. Use of a supported liquid membrane formed by the method for in situ formation of a supported liquid membrane according to any one of claims 1 to 6 in liquid phase microextraction, electromembrane extraction or a combination thereof.

8. The use according to claim 7, characterized in that: When the application is liquid-phase microextraction, the steps are as follows: adding a sample solution to the donor phase chamber, placing the membrane carrier material in the groove above the donor phase chamber, screwing it into the receiving phase chamber and adding the mixed receiving phase working solution thereto, placing the assembled extraction device on a constant temperature mixer and oscillating it, so that the target in the sample solution passes through the supported liquid membrane formed in situ and enters the receiving phase working solution.

9. The use according to claim 7, characterized in that: When the application is electromembrane extraction, the steps include: (1) Add the sample solution to the donor phase chamber where the stainless steel electrode is inserted, place the membrane support material in the groove above the donor phase chamber, screw it into the receiving phase chamber and add the mixed receiving phase working solution, and insert the platinum wire electrode into the receiving phase working solution through the electrode fixing block; (2) The two electrodes are connected to the positive and negative poles of a DC constant voltage power supply, respectively, and the device of step (1) is placed on a constant temperature mixer for oscillation, so that the target in the sample solution passes through the in situ formed support liquid membrane under the action of the electric field and enters the receiving phase.

10. The use according to claim 9, characterized in that: In step (2), the voltage of the DC constant voltage power supply is 2-200V, and the speed of the constant temperature mixer is 500-1000rpm; the scope of application includes but is not limited to pre-treatment of wastewater, urine or blood.

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