An extraction method based on a solid phase microextraction fiber-adsorption extraction stir bar combined device

Abstract

The application belongs to the technical field of solid phase microextraction, and discloses a solid phase microextraction fiber-adsorption extraction stirring rod combined device and a use method. The combined device comprises a fixed bottle cap, an adsorption extraction chamber, a solid phase microextraction fiber and an adsorption extraction stirring rod. The adsorption extraction stirring rod is placed at the bottom of the adsorption extraction chamber, the solid phase microextraction fiber is suspended and fixed in the adsorption extraction chamber through the fixed bottle cap, and the adsorption extraction chamber is connected with the fixed bottle cap through external threads. The combined device can be used for liquid-liquid combined extraction and gas-liquid combined extraction, competition adsorption caused by an additional stirring rod is avoided, the problem of insufficient enrichment caused by volatilization of part of analytes is avoided, and the extraction rate is improved.

Description

Technical Field

[0001] This invention relates to the field of solid-phase microextraction technology, and in particular to an extraction method based on a solid-phase microextraction fiber-adsorption extraction stirring rod combined device. Background Technology

[0002] Traditional solid-phase microextraction (SPE) techniques, employing only direct extraction or headspace extraction, suffer from drawbacks such as analyte adhesion to the container walls or volatilization, leading to a decrease in the actual extraction yield. Furthermore, direct and headspace extraction methods typically require a stir bar for homogenization, which can cause some analytes to adhere to the stir bar, further reducing extraction efficiency. Simultaneously, the volatilization and resolution of volatilized analytes also contribute to the reduced actual extraction yield in direct and headspace extraction methods. Therefore, traditional SPE techniques struggle to eliminate losses due to analyte volatilization or subsequent resolution, resulting in insufficient enrichment. Summary of the Invention

[0003] The purpose of this invention is to provide an extraction method based on a solid-phase microextraction fiber-adsorption extraction stirring rod combined device, which solves the problems of insufficient extraction and easy adsorption of stirring rods in traditional solid-phase microextraction technology.

[0004] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0005] The present invention provides a device for the combined use of solid-phase microextraction fiber and adsorption extraction stirring rod, including a fixed bottle cap 1, an adsorption extraction chamber 2, a solid-phase microextraction fiber 3 and an adsorption extraction stirring rod 4.

[0006] The adsorption extraction stirring rod 4 is placed at the bottom of the adsorption extraction chamber 2, and the solid phase microextraction fiber 3 is suspended and fixed in the adsorption extraction chamber 2 by the fixed bottle cap 1. The adsorption extraction chamber 2 and the fixed bottle cap 1 are connected by threads.

[0007] Preferably, in the combined device, the fixing cap 1 is filled with a fixing material.

[0008] Preferably, in the combined device, the fixing material includes a rubber gasket.

[0009] Preferably, in the combined device, the height of the adsorption extraction chamber 2 is greater than the length of the solid-phase microextraction fiber 3 fixed in the adsorption extraction chamber 2.

[0010] Preferably, in the combined apparatus, the length of the adsorption-extraction stirring rod 4 is smaller than the bottom inner diameter of the adsorption-extraction chamber 2.

[0011] Preferably, in the combined device, rubber sleeves are provided at both ends of the adsorption extraction stirring rod 4.

[0012] Preferably, in the combined device, the length ratio of the rubber sleeve to the adsorption extraction stirring rod 4 is 2~3mm:20~22mm.

[0013] The present invention also provides an extraction method based on a solid-phase microextraction fiber-adsorption extraction stirring rod combined device, comprising the following steps: adding the liquid phase to be extracted into the adsorption extraction chamber 2; simultaneously placing the solid-phase microextraction fiber 3 and the adsorption extraction stirring rod 4 into the liquid phase to be extracted; threading the fixed bottle cap 1 to the adsorption extraction chamber 2; assembling the combined device; and performing extraction.

[0014] Alternatively, the extraction method may include the following steps: adding the liquid phase to be extracted into the adsorption extraction chamber 2; suspending the solid-phase microextraction fiber 3 in the gas phase of the adsorption extraction chamber 2 without contacting the liquid phase to be extracted, while placing the adsorption extraction stirring rod 4 into the liquid phase to be extracted, and threading the fixed bottle cap 1 to the adsorption extraction chamber 2, thus completing the assembly of the combined device and performing extraction.

[0015] Preferably, in the extraction method, the coupling device used during extraction is a closed system.

[0016] As can be seen from the above technical solution, compared with the prior art, the present invention has the following beneficial effects:

[0017] The solid-phase microextraction fiber-adsorption extraction stirring rod combined device described in this invention can be used for both liquid-liquid and gas-liquid extraction. When using liquid-liquid extraction, the solid-phase microextraction fiber and the adsorption extraction stirring rod simultaneously complete adsorption, avoiding competitive adsorption introduced by an external stir bar and improving the extraction rate. Furthermore, by completely immersing the adsorption coating of the solid-phase microextraction fiber and the adsorption extraction stirring rod in the liquid phase, the volume of the extraction phase is increased, further improving the extraction rate, with a significantly higher extraction yield than single extraction modes. When using gas-liquid extraction, the solid-phase microextraction fiber is completely suspended in the liquid phase, avoiding insufficient enrichment due to partial analyte volatilization and improving the extraction rate. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below.

[0019] Figure 1 This is a schematic diagram of a combined device of solid-phase microextraction fiber and adsorption extraction stirring rod, wherein 1 is a fixed bottle cap, 2 is an adsorption extraction chamber, 3 is a solid-phase microextraction fiber, and 4 is an adsorption extraction stirring rod.

[0020] Figure 2The chromatograms are of the extraction effects of Example 1 and Comparative Examples 1-2, where peak 1 is bisphenol A;

[0021] Figure 3 The chromatograms show the extraction effects of Examples 2 and Comparative Examples 3-4, where peak 2 represents ethylparaben. Detailed Implementation

[0022] This invention provides a combined device for solid-phase microextraction fiber and adsorption extraction stirring rod, such as... Figure 1 As shown, it includes a fixed bottle cap 1, an adsorption extraction chamber 2, a solid-phase microextraction fiber 3, and an adsorption extraction stirring rod 4;

[0023] The adsorption extraction stirring rod 4 is placed at the bottom of the adsorption extraction chamber 2, and the solid phase microextraction fiber 3 is suspended and fixed in the adsorption extraction chamber 2 by the fixed bottle cap 1. The adsorption extraction chamber 2 and the fixed bottle cap 1 are connected by threads.

[0024] In this invention, the threaded connection is preferably an external threaded connection.

[0025] In this invention, the fixed cap 1 is preferably filled with a fixing material. The purpose of filling with the fixing material is to suspend and fix the solid-phase microextraction fiber in a specific position within the adsorption extraction chamber, and to improve the sealing of the adsorption extraction chamber, preventing the analyte from volatilizing and causing loss.

[0026] In this invention, the connection method between the fixed bottle cap 1 and the solid-phase microextraction fiber 3 is preferably: the solid-phase microextraction fiber 3 passes through the hole in the fixed bottle cap 1 filled with fixing material, and is fixed by the fixing material, thereby adjusting the position of the solid-phase microextraction fiber 3.

[0027] In this invention, the fixing material preferably includes a rubber gasket.

[0028] In this invention, the height of the adsorption extraction chamber 2 is preferably greater than the length of the solid-phase microextraction fiber 3 fixed within the adsorption extraction chamber 2. This is to ensure that the solid-phase microextraction fiber can be suspended and fixed within the adsorption extraction chamber by the bottle cap.

[0029] In this invention, the length of the adsorption extraction stirring rod 4 is preferably smaller than the bottom inner diameter of the adsorption extraction chamber 2. This is to ensure that the adsorption extraction stirring rod can rotate within the adsorption extraction chamber.

[0030] In this invention, rubber sleeves are preferably provided at both ends of the adsorption extraction stirring rod 4. The purpose is to reduce the direct contact between the adsorption extraction stirring rod and the bottom of the adsorption extraction chamber, thereby reducing losses caused by stirring in the adsorption extraction chamber, while increasing the contact area of ​​the adsorption extraction stirring rod.

[0031] In this invention, the length ratio of the rubber sleeve to the adsorption extraction stirring rod 4 is preferably 2~3mm:20~22mm.

[0032] In this invention, the types of the solid-phase microextraction fiber 3 and the adsorption extraction stirring rod 4 are not limited, and materials or preparation methods well known to those skilled in the art can be used. Specifically, in the embodiments of this invention, the solid-phase microextraction fiber 3 and the adsorption extraction stirring rod 4 are illustrated by way of molecularly imprinted coating materials.

[0033] The present invention also provides an extraction method based on a solid-phase microextraction fiber-adsorption extraction stirring rod combined device, preferably including the following steps: adding the liquid phase to be extracted into the adsorption extraction chamber 2; simultaneously placing the solid-phase microextraction fiber 3 and the adsorption extraction stirring rod 4 into the liquid phase to be extracted; threading the fixed bottle cap 1 to the adsorption extraction chamber 2; assembling the combined device; and performing extraction.

[0034] Alternatively, the extraction method preferably includes the following steps: adding the liquid phase to be extracted into the adsorption extraction chamber 2; suspending the solid-phase microextraction fiber 3 in the gas phase of the adsorption extraction chamber 2 without contacting the liquid phase to be extracted, while placing the adsorption extraction stirring rod 4 into the liquid phase to be extracted, and threading the fixed bottle cap 1 to the adsorption extraction chamber 2, thus completing the assembly of the combined device and performing extraction.

[0035] In this invention, the combined extraction device is preferably sealed. The solid-phase microextraction fiber 3 and the fixed cap 1 in the combined device are fixed by filling with a fixing material; then the fixed cap 1 is threadedly connected to the adsorption extraction chamber 2 to achieve a seal, thus ensuring the airtightness of the combined device.

[0036] In this invention, the parameters and conditions of the extraction method are not limited, and solutions well known to those skilled in the art can be used.

[0037] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0038] Example 1

[0039] This embodiment provides a method for extracting bisphenol A using a combined device based on molecularly imprinted solid-phase microextraction fiber and molecularly imprinted adsorption extraction stirring rod, comprising the following steps:

[0040] (1) Prepare bisphenol A molecularly imprinted solid-phase microextraction fiber 3 and bisphenol A molecularly imprinted adsorption extraction stirring rod 4 respectively.

[0041] The preparation method of bisphenol A molecularly imprinted solid-phase microextraction fiber 3 includes the following steps:

[0042] 1 mmol of bisphenol A and 4 mmol of acrylamide were dissolved in 5 mL of acetonitrile and prepolymerized at room temperature for 12 h to obtain a template-monomer mixed solution. Then, 30 mmol of ethylene glycol dimethacrylate and 50 mg of azobisisobutyronitrile were added to the template-monomer mixed solution. After ultrasonic mixing, nitrogen gas was blown to remove oxygen. Finally, the mixed solution was injected into the glass capillary jacket using a syringe and inserted into the silanized capillary liner. The gap between the two capillaries was sealed with a rubber band to isolate air. The mixture was placed in a constant temperature water bath at 60 °C for 24 h to polymerize. After the reaction was completed, the imprinted coating was cut to a length of 18 mm and washed with a methanol-acetic acid (9:1) mixed solution to obtain bisphenol A molecularly imprinted solid-phase microextraction fiber 3.

[0043] The preparation method of the molecularly imprinted adsorption extraction stirring rod 4 for bisphenol A includes the following steps:

[0044] The cleaned and dried iron core was placed into a 22 mm silanized capillary tube. The other end of the capillary tube was melted and sealed as a stir bar. Then, 1 mmol of bisphenol A and 4 mmol of acrylamide were dissolved in 5 mL of acetonitrile and prepolymerized at room temperature for 12 h to obtain a template-monomer mixed solution. Then, 30 mmol of ethylene glycol dimethacrylate and 50 mg of azobisisobutyronitrile were added to the template-monomer mixed solution. After ultrasonic mixing, nitrogen gas was blown to remove oxygen. Finally, the mixed solution was injected into the glass capillary tube jacket using a syringe. The prepared stir bar was placed in the capillary tube and the gap between the two capillaries was sealed with a rubber band to isolate air. The mixture was heated in a water bath to initiate the polymerization reaction. After the reaction was completed, the core was removed and the coating length was cut to 18 mm, with both ends exposed. A 2 mm rubber sleeve was put on the core and the core was washed with methanol-acetic acid (9:1) solution to obtain the molecular imprinted adsorption extraction stir bar 4 of bisphenol A.

[0045] (2) Take 50 mL of 100 μg / L bisphenol A solution and put it into the adsorption extraction chamber 2. Place the molecularly imprinted adsorption extraction stirring rod 4 at the bottom of the adsorption extraction chamber 2. Pass the molecularly imprinted solid microextraction fiber 3 through the hole on the fixed bottle cap 1 filled with rubber gasket, and fix the molecularly imprinted solid microextraction fiber 3 through the rubber gasket. Adjust the adsorption coating of the molecularly imprinted solid microextraction fiber 3 to be completely immersed in the solution. Connect the adsorption extraction chamber 2 to the fixed bottle cap 1 that fixes the molecularly imprinted solid microextraction fiber 3 through the external thread. After sealing, the combined device is assembled.

[0046] (3) Place the combined device on a magnetic stirrer and perform adsorption extraction for 150 min.

[0047] Comparative Example 1

[0048] This comparative example provides a method for extracting bisphenol A using an apparatus containing a molecularly imprinted adsorption extraction stirring rod, comprising the following steps:

[0049] (1) The molecularly imprinted adsorption extraction stirring rod 4 for bisphenol A was prepared by the method in step (1) of Example 1;

[0050] (2) Take 50 mL of 100 μg / L bisphenol A solution and put it into the adsorption extraction chamber 2. Place the molecularly imprinted adsorption extraction stirring rod 4 at the bottom of the adsorption extraction chamber 2. Connect the adsorption extraction chamber 2 to the fixed bottle cap 1 through the external thread. After sealing, the device is assembled.

[0051] (3) Place the device on a magnetic stirrer and perform adsorption extraction for 150 min.

[0052] Comparative Example 2

[0053] This comparative example provides a method for extracting bisphenol A using a device containing molecularly imprinted solid-phase microextraction fibers, comprising the following steps:

[0054] (1) Bisphenol A molecularly imprinted solid-phase microextraction fiber 3 was prepared using the method in step (1) of Example 1;

[0055] (2) Take 50 mL of 100 μg / L bisphenol A solution and put it into the adsorption extraction chamber 2. Fix the molecularly imprinted solid microextraction fiber 3 with the fixed bottle cap 1. Adjust the adsorption coating of the molecularly imprinted solid microextraction fiber 3 to be completely immersed in the solution. Connect the adsorption extraction chamber 2 to the fixed bottle cap 1 of the fixed molecularly imprinted solid microextraction fiber 3 through the external thread. After sealing, the device is assembled.

[0056] (3) Place the device on a magnetic stirrer and perform adsorption extraction for 150 min.

[0057] Test Example 1

[0058] (1) Take out the molecularly imprinted solid-phase microextraction fiber 3 and molecularly imprinted adsorption extraction stirring rod 4 after extraction in Example 1, the molecularly imprinted adsorption extraction stirring rod 4 after extraction in Comparative Example 1, and the molecularly imprinted solid-phase microextraction fiber 3 after extraction in Comparative Example 2, and desorb them by ultrasonication with 200 μL of methanol for 10 min respectively.

[0059] (2) The above three desorption solutions were analyzed by high performance liquid chromatography. The liquid chromatography conditions were as follows: C18 column, mobile phase chromatographic acetonitrile / water (50:50, v / v), column temperature 30℃, flow rate 1mL / min, dual wavelength detection, and detection wavelengths of 225nm and 254nm.

[0060] The peak areas of the eluents obtained under the three extraction conditions of Example 1 and Comparative Examples 1-2 were analyzed, and the results are as follows: Figure 2 As shown. Figure 2 The results showed that the peak area of ​​bisphenol A extracted using Example 1 was 43.52 mAU·min, while the peak areas of bisphenol A extracted using Comparative Example 2 and Comparative Example 1 were 20.22 mAU·min and 29.52 mAU·min, respectively. Therefore, compared to methods using a single extraction fiber or a single extraction stirring rod, the peak area of ​​bisphenol A extracted using the combined device described in this invention is 2.15 times that of a single extraction fiber and 1.47 times that of a single extraction stirring rod. This indicates that the extraction efficiency of the combined device is significantly higher than that of a single extraction method.

[0061] Example 2

[0062] This embodiment provides a method for extracting ethylparaben using a combined device based on molecularly imprinted solid-phase microextraction fiber and molecularly imprinted adsorption extraction stirring rod, comprising the following steps:

[0063] (1) Molecularly imprinted solid-phase microextraction fiber 3 and molecularly imprinted adsorption extraction stirring rod 4 of ethylparaben were prepared respectively.

[0064] The preparation method of ethylparaben-imprinted solid-phase microextraction fiber 3 includes the following steps:

[0065] 1 mmol of ethylparaben and 4 mmol of acrylamide were dissolved in 5 mL of acetonitrile and prepolymerized at room temperature for 12 h to obtain a template-monomer mixed solution. Then, 30 mmol of ethylene glycol dimethacrylate and 50 mg of azobisisobutyronitrile were added to the template-monomer mixed solution. After ultrasonic mixing, nitrogen gas was blown to remove oxygen. Finally, the mixed solution was injected into the glass capillary jacket using a syringe and inserted into the silanized capillary liner. The gap between the two capillaries was sealed with a rubber band to isolate air. The mixture was placed in a constant temperature water bath at 60 °C for 24 h to polymerize. After the reaction was completed, the imprinted coating was cut to a length of 18 mm and washed with a methanol-acetic acid (9:1) mixed solution to obtain molecularly imprinted solid-phase microextraction fiber 3 of ethylparaben.

[0066] The preparation method of the molecularly imprinted adsorption extraction stirring rod 4 for ethylparaben includes the following steps:

[0067] The cleaned and dried iron core was placed into a 22 mm silanized capillary tube. The other end of the capillary tube was melted and sealed as a stir bar. Then, 1 mmol of ethylparaben and 4 mmol of acrylamide were dissolved in 5 mL of acetonitrile and prepolymerized at room temperature for 12 h to obtain a template-monomer mixed solution. Then, 30 mmol of ethylene glycol dimethacrylate and 50 mg of azobisisobutyronitrile were added to the template-monomer mixed solution. After ultrasonic mixing, nitrogen gas was blown to remove oxygen. Finally, the mixed solution was injected into the glass capillary tube jacket using a syringe. The prepared stir bar was placed in the capillary tube and the gap between the two capillaries was sealed with a rubber band to isolate air. The mixture was heated in a water bath to initiate the polymerization reaction. After the reaction was completed, the core was removed and the coating length was cut to 18 mm, with both ends exposed. A 2 mm rubber sleeve was put on the core and the core was washed with methanol-acetic acid (9:1) solution to obtain the molecular imprinted adsorption extraction stir bar 4 of ethylparaben.

[0068] (2) Take 50 mL of ethylparaben solution with a concentration of 100 μg / L and put it into the adsorption extraction chamber 2. Place the molecularly imprinted adsorption extraction stirring rod 4 at the bottom of the adsorption extraction chamber 2. Pass the molecularly imprinted solid microextraction fiber 3 through the hole on the fixed bottle cap 1 filled with rubber gaskets and fix the molecularly imprinted solid microextraction fiber 3 through the rubber gaskets. Adjust the adsorption coating of the molecularly imprinted solid microextraction fiber 3 to be completely immersed in the solution. Connect the adsorption extraction chamber 2 to the fixed bottle cap 1 that fixes the molecularly imprinted solid microextraction fiber 3 through the external thread. After sealing, the combined device is assembled.

[0069] (3) Place the combined device on a magnetic stirrer and perform adsorption extraction for 150 min.

[0070] Comparative Example 3

[0071] This comparative example provides a method for extracting ethylparaben from a device containing a molecularly imprinted adsorption extraction stirring rod, comprising the following steps:

[0072] (1) Molecularly imprinted adsorption extraction stirring rod 4 for ethylparaben was prepared using the method in step (1) of Example 2;

[0073] (2) Take 50 mL of ethylparaben solution with a concentration of 100 μg / L and put it into the adsorption extraction chamber 2. Place the molecularly imprinted adsorption extraction stirring rod 4 at the bottom of the adsorption extraction chamber 2. Connect the adsorption extraction chamber 2 to the fixed bottle cap 1 through the external thread. After sealing, the device is assembled.

[0074] (3) Place the device on a magnetic stirrer and perform adsorption extraction for 150 min.

[0075] Comparative Example 4

[0076] This comparative example provides a method for extracting ethylparaben from a device containing molecularly imprinted solid-phase microextraction fibers, comprising the following steps:

[0077] (1) Molecularly imprinted solid-phase microextraction fiber 3 of ethylparaben was prepared by the method in step (1) of Example 2;

[0078] (2) Take 50 mL of ethylparaben solution with a concentration of 100 μg / L and put it into the adsorption extraction chamber 2. Fix the molecularly imprinted solid microextraction fiber 3 with the fixed bottle cap 1. Adjust the adsorption coating of the molecularly imprinted solid microextraction fiber 3 to be completely immersed in the solution. Connect the adsorption extraction chamber 2 to the fixed bottle cap 1 of the fixed molecularly imprinted solid microextraction fiber 3 through the external thread. After sealing, the device is assembled.

[0079] (3) Place the device on a magnetic stirrer and perform adsorption extraction for 150 min.

[0080] Test Example 2

[0081] (1) Take out the molecularly imprinted solid-phase microextraction fiber 3 and molecularly imprinted adsorption extraction stirring rod 4 after extraction in Example 2, the molecularly imprinted adsorption extraction stirring rod 4 after extraction in Comparative Example 3, and the molecularly imprinted solid-phase microextraction fiber 3 after extraction in Comparative Example 4, and desorb them by ultrasonication with 200 μL of methanol for 10 min respectively.

[0082] (2) The above three desorption solutions were analyzed by high performance liquid chromatography. The liquid chromatography conditions were as follows: C18 column, mobile phase chromatographic acetonitrile / water (50:50, v / v), column temperature 30℃, flow rate 1mL / min, dual wavelength detection, and detection wavelengths of 225nm and 254nm.

[0083] The peak areas of the eluents obtained under the three extraction conditions of Example 2 and Comparative Examples 3-4 were analyzed, and the results are as follows: Figure 3 As shown. Figure 3 The results showed that the peak area of ​​ethylparaben extracted using Example 2 was 7.94 mAU·min, while the peak areas of ethylparaben extracted using Comparative Example 4 or Comparative Example 3 were 4.32 mAU·min and 4.77 mAU·min, respectively. Therefore, compared to methods using a single extraction fiber or a single extraction stir bar, the peak area of ​​ethylparaben extracted using the combined device described in this invention is 1.84 times that of a single extraction fiber and 1.67 times that of a single extraction stir bar. This indicates that the extraction efficiency of the combined device is significantly higher than that of a single extraction method.

[0084] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An extraction method based on a combination of solid phase microextraction fiber-adsorptive extraction stir bar, characterized by, The solid phase microextraction fiber-adsorption extraction stirring rod combined device comprises a fixed bottle cap (1), an adsorption extraction chamber (2), a solid phase microextraction fiber (3) and an adsorption extraction stirring rod (4). The adsorption extraction stirring rod (4) is placed at the bottom of the adsorption extraction chamber (2), the solid phase microextraction fiber (3) is suspended and fixed in the adsorption extraction chamber (2) through the fixed bottle cap (1), and the adsorption extraction chamber (2) and the fixed bottle cap (1) are connected through threads. The extraction method comprises the following steps: adding a liquid phase to be extracted into the adsorption extraction chamber (2); simultaneously placing the solid phase microextraction fiber (3) and the adsorption extraction stirring rod (4) into the liquid phase to be extracted, threadedly connecting the fixed bottle cap (1) and the adsorption extraction chamber (2), assembling the combined device, and performing extraction.

2. The extraction method according to claim 1, characterized in that, The fixed bottle cap (1) is filled with a fixed material.

3. The extraction method according to claim 2, characterized in that, The fixed material comprises a rubber gasket.

4. The extraction method according to any one of claims 1 to 3, characterized in that, The height of the adsorption extraction chamber (2) is greater than the length of the solid phase microextraction fiber (3) fixed in the adsorption extraction chamber (2).

5. The extraction method according to claim 4, characterized in that, The length of the adsorption extraction stirring rod (4) is less than the inner diameter of the bottom of the adsorption extraction chamber (2).

6. The extraction method according to claim 1 or 5, characterized in that, Rubber pipe sleeves are arranged at both ends of the adsorption extraction stirring rod (4).

7. The extraction method according to claim 6, characterized in that, The length ratio of the rubber pipe sleeve to the adsorption extraction stirring rod (4) is 2-3 mm: 20-22 mm.

8. The extraction method of claim 1, wherein, The combined device during extraction is closed.

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