Solid-phase microextraction fiber-adsorption extraction stirring rod combined device and use method of solid-phase microextraction fiber-adsorption extraction stirring rod combined device

Abstract

The invention 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 and extraction chamber, solid-phase micro-extraction fibers and an adsorption and extraction stirring rod, the adsorption and extraction stirring rod is placed at the bottom of the adsorption and extraction chamber, the solid-phase micro-extraction fiber is fixed in the adsorption and extraction chamber in a suspended manner through the fixed bottle cap, and the adsorption and extraction chamber is connected with the fixed bottle cap through external threads. The combined device provided by the invention not only can be used for liquid-liquid combined extraction, but also can be used for gas-liquid combined extraction, so that competitive adsorption introduced by an additional stirrer is effectively avoided, meanwhile, the problem of insufficient enrichment caused by volatilization of part of analytes is avoided, and the extraction rate is improved.

Description

Technical Field

[0001] The invention relates to the technical field of solid phase microextraction, and in particular to a combined device of a solid phase microextraction fiber-adsorption extraction stirring rod and a use method thereof. Background Art

[0002] Traditional solid phase microextraction technology only uses direct extraction or headspace extraction methods, which has the defect that some analytes adhere to the container wall or volatilize, resulting in a decrease in the actual extraction rate. In addition, in the direct extraction and headspace extraction methods, a stirring bar is usually required to evenly mix the solution, which will cause some analytes to easily adhere to the stirring bar, resulting in a decrease in extraction efficiency. At the same time, the volatilization of some analytes and the re-dissolution of volatilized analytes will also lead to a decrease in the actual extraction amount of direct extraction and headspace extraction methods. Therefore, it is difficult for traditional solid phase microextraction technology to eliminate the loss caused by the volatilization of analytes or the re-dissolution after volatilization, and there is a problem of insufficient enrichment. Summary of the invention

[0003] The purpose of the present invention is to provide a combined device of solid phase microextraction fiber-adsorption extraction stirring rod and a method of using the same, so as to solve the problems of insufficient extraction and easy adsorption of the stirring rod in traditional solid phase microextraction technology.

[0004] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0005] The present invention provides a combined device of solid phase microextraction fiber and adsorption extraction stirring rod, comprising 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 through the fixed bottle cap 1, and the adsorption extraction chamber 2 is connected to the fixed bottle cap 1 through threads.

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

[0008] Preferably, in the combined device, the fixing material comprises 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 device, 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 tube 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 tube sleeve to the adsorption extraction stirring rod 4 is 2-3 mm: 20-22 mm.

[0013] The present invention also provides a method for using the combined device, which comprises the following steps: adding the liquid phase to be extracted into the adsorption extraction chamber 2; placing the solid phase microextraction fiber 3 and the adsorption extraction stirring rod 4 into the liquid phase to be extracted at the same time, threading the fixed bottle cap 1 and the adsorption extraction chamber 2, assembling the combined device, and performing extraction;

[0014] Alternatively, the method of use 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, and placing the adsorption extraction stirring rod 4 into the liquid phase to be extracted, threading the fixed bottle cap 1 and the adsorption extraction chamber 2, assembling the combined device, and performing extraction.

[0015] Preferably, in the method of use, the combined device for extraction is closed.

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

[0017] The combined device of solid phase microextraction fiber and adsorption extraction stirring rod of the present invention can be used for both liquid-liquid extraction and gas-liquid extraction. When liquid-liquid extraction is adopted, the solid phase microextraction fiber and the adsorption extraction stirring rod complete adsorption at the same time, avoiding competitive adsorption introduced by the external stirring rod, thereby improving the extraction rate; and 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, the extraction rate is improved, and the extraction amount is significantly higher than that of a single extraction mode. When gas-liquid extraction is adopted, the solid phase microextraction fiber is completely suspended in the liquid phase, thereby avoiding the problem of insufficient enrichment due to the volatilization of some analytes and improving the extraction rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required to be used in the description of the embodiments or the prior art are briefly introduced below.

[0019] Figure 1 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 of the extraction effects of Example 1 and Comparative Examples 1-2 are shown, wherein Peak 1 is bisphenol A;

[0021] Figure 3 It is the extraction effect chromatogram of Example 2 and Comparative Examples 3-4, wherein Peak 2 is ethyl paraben. DETAILED DESCRIPTION

[0022] The present invention provides a solid phase microextraction fiber-adsorption extraction stirring rod combined device, 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 through the fixed bottle cap 1, and the adsorption extraction chamber 2 is connected to the fixed bottle cap 1 through threads.

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

[0025] In the present invention, the fixing bottle cap 1 is preferably filled with fixing material. The purpose of filling the fixing material is to suspend the solid phase microextraction fiber in a specific position in the adsorption extraction chamber, improve the sealing of the adsorption extraction chamber, and prevent the loss of the analyte due to volatilization.

[0026] In the present 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 a fixing material and is fixed by the fixing material, thereby adjusting the position of the solid phase microextraction fiber 3.

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

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

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

[0030] In the present 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, reduce the loss caused by stirring in the adsorption extraction chamber, and increase the contact area of ​​the adsorption extraction stirring rod.

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

[0032] In the present invention, the types of the solid phase microextraction fiber 3 and the adsorption extraction stirring rod 4 are not limited, and the materials or preparation methods familiar to those skilled in the art can be used. Specifically in the embodiment of the present invention, the solid phase microextraction fiber 3 and the adsorption extraction stirring rod 4 are exemplified by molecular imprinting coating materials.

[0033] The present invention also provides a method for using the combined device, which preferably includes the following steps: adding the liquid phase to be extracted into the adsorption extraction chamber 2; placing the solid phase microextraction fiber 3 and the adsorption extraction stirring rod 4 into the liquid phase to be extracted at the same time, threading the fixed bottle cap 1 and the adsorption extraction chamber 2, assembling the combined device, and performing extraction;

[0034] Alternatively, the method of use 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, and placing the adsorption extraction stirring rod 4 into the liquid phase to be extracted, threading the fixed bottle cap 1 and the adsorption extraction chamber 2, assembling the combined device, and performing extraction.

[0035] In the present invention, the combined device for extraction is preferably airtight. The solid phase microextraction fiber 3 in the combined device is fixed to the fixed bottle cap 1 by filling with a fixing material; then the fixed bottle cap 1 is threadedly connected to the adsorption extraction chamber 2 to achieve sealing, thereby ensuring the airtightness of the combined device.

[0036] In the present invention, the parameter conditions in the method of use are not limited, and schemes well known to those skilled in the art can be adopted.

[0037] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work 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 molecular imprinting solid phase microextraction fiber-molecular imprinting adsorption extraction stirring rod combined device, comprising the following steps:

[0040] (1) preparing a molecularly imprinted solid phase microextraction fiber 3 of bisphenol A and a molecularly imprinted adsorption extraction stirring rod 4 of bisphenol A respectively;

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

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

[0043] The method for preparing the molecular imprinting adsorption extraction stirring bar 4 of bisphenol A comprises the following steps:

[0044] Place the cleaned and dried iron core into a 22 mm silanized capillary, melt and seal the other end of the capillary to serve as a stirrer, then dissolve 1 mmol bisphenol A and 4 mmol acrylamide in 5 mL acetonitrile, prepolymerize for 12 h at room temperature to obtain a template-monomer mixed solution; then add 30 mmol ethylene glycol dimethacrylate and 50 mg azobisisobutyronitrile to the template-monomer mixed solution, mix evenly with ultrasound, blow nitrogen to remove oxygen, finally inject the mixed solution into the glass capillary jacket with a syringe, put in the stirrer prepared in advance, seal the gap between the two capillaries with a rubber band to isolate the air, heat in a water bath to initiate the polymerization reaction, take out after the reaction is completed, cut off the coating length of 18 mm, expose both ends at the same time, put on a 2 mm rubber sleeve, and wash with a methanol-acetic acid (9:1) solution to obtain a molecular imprinting adsorption extraction stirring rod 4 of bisphenol A;

[0045] (2) 50 mL of 100 μg / L bisphenol A solution was loaded into the adsorption extraction chamber 2, and the molecular imprinting adsorption extraction stirring rod 4 was placed at the bottom of the adsorption extraction chamber 2. The molecular imprinting solid phase microextraction fiber 3 was passed through the hole on the fixed bottle cap 1 filled with a rubber gasket, and the molecular imprinting solid phase microextraction fiber 3 was fixed by the rubber gasket. The adsorption coating of the molecular imprinting solid phase microextraction fiber 3 was adjusted to be completely immersed in the solution, and the adsorption extraction chamber 2 was connected to the fixed bottle cap 1 fixed with the molecular imprinting solid phase microextraction fiber 3 through an external thread. After sealing, the combined device was 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 a device containing a molecularly imprinted adsorption extraction stirring rod, comprising the following steps:

[0049] (1) The method of step (1) of Example 1 was used to prepare a molecularly imprinted adsorption extraction stirring bar 4 of bisphenol A;

[0050] (2) 50 mL of 100 μg / L bisphenol A solution was loaded into the adsorption extraction chamber 2, the molecular imprinting adsorption extraction stirring rod 4 was placed at the bottom of the adsorption extraction chamber 2, the adsorption extraction chamber 2 was connected to the fixed bottle cap 1 through an external thread, and the device was assembled after sealing;

[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 a molecularly imprinted solid phase microextraction fiber, comprising the following steps:

[0054] (1) The method of step (1) of Example 1 was used to prepare a molecularly imprinted solid phase microextraction fiber 3 for bisphenol A;

[0055] (2) 50 mL of 100 μg / L bisphenol A solution was loaded into the adsorption extraction chamber 2, and the molecular imprinted solid phase microextraction fiber 3 was fixed with the fixed bottle cap 1, and the adsorption coating of the molecular imprinted solid phase microextraction fiber 3 was adjusted to be completely immersed in the solution. The adsorption extraction chamber 2 was connected to the fixed bottle cap 1 fixed with the molecular imprinted solid phase microextraction fiber 3 through the external thread, and the device was assembled after sealing;

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

[0057] Test Example 1

[0058] (1) The molecular imprinted solid phase microextraction fiber 3 and the molecular imprinted adsorption extraction stirring rod 4 after the extraction in Example 1, the molecular imprinted adsorption extraction stirring rod 4 after the extraction in Comparative Example 1, and the molecular imprinted solid phase microextraction fiber 3 after the extraction in Comparative Example 2 were taken out, and ultrasonically desorbed with 200 μL of methanol for 10 min respectively;

[0059] (2) The three desorbents were analyzed by HPLC. The conditions of HPLC were as follows: a C18 column, a mobile phase of acetonitrile / water (50:50, v / v), a column temperature of 30°C, a flow rate of 1 mL / min, and dual-wavelength detection at wavelengths of 225 nm and 254 nm.

[0060] The peak areas of the analytical solutions obtained under the three extraction conditions of Example 1 and Comparative Examples 1 to 2 were analyzed, and the results were as follows: Figure 2 shown. Figure 2 The results show that the peak area of ​​bisphenol A extracted using Example 1 is 43.52 mAU·min, and the peak areas of bisphenol A extracted using Comparative Example 2 or Comparative Example 1 are 20.22 mAU·min and 29.52 mAU·min, respectively. Therefore, compared with the scheme using a single extraction fiber or a single extraction stirring rod, the peak area of ​​bisphenol A extracted using the combined device of the present invention is 2.15 times that of a single extraction fiber and 1.47 times that of a single extraction stirring rod, which indicates that the extraction efficiency of the combined device is significantly higher than the extraction efficiency of a single extraction method.

[0061] Example 2

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

[0063] (1) preparing a molecularly imprinted solid phase microextraction fiber 3 of ethyl paraben and a molecularly imprinted adsorption extraction stirring rod 4 of ethyl paraben respectively;

[0064] The preparation method of molecular imprinted solid phase microextraction fiber 3 of ethyl paraben comprises the following steps:

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

[0066] The preparation method of the molecular imprinting adsorption extraction stirring bar 4 of ethyl paraben comprises the following steps:

[0067] Place the cleaned and dried iron core into a 22 mm silanized capillary, melt and seal the other end of the capillary to serve as a stirrer, then dissolve 1 mmol of ethylparaben and 4 mmol of acrylamide in 5 mL of acetonitrile, prepolymerize for 12 h at room temperature to obtain a template-monomer mixed solution; then add 30 mmol of ethylene glycol dimethacrylate and 50 mg of azobisisobutyronitrile to the template-monomer mixed solution, mix evenly with ultrasound, blow nitrogen to remove oxygen, finally inject the mixed solution into the outer jacket of the glass capillary using a syringe, place the stirrer prepared in advance, seal the gap between the two capillaries with a rubber band to isolate the air, heat in a water bath to initiate the polymerization reaction, take it out after the reaction is completed, cut off the coating length of 18 mm, expose both ends at the same time, put on a 2 mm rubber sleeve, and wash it with a methanol-acetic acid (9:1) solution to obtain a molecular imprinting adsorption extraction stirring rod 4 of ethylparaben;

[0068] (2) 50 mL of 100 μg / L ethyl paraben solution was loaded into the adsorption extraction chamber 2, and the molecular imprinting adsorption extraction stirring rod 4 was placed at the bottom of the adsorption extraction chamber 2. The molecular imprinting solid phase microextraction fiber 3 was passed through the hole on the fixed bottle cap 1 filled with a rubber gasket, and the molecular imprinting solid phase microextraction fiber 3 was fixed by the rubber gasket. The adsorption coating of the molecular imprinting solid phase microextraction fiber 3 was adjusted to be completely immersed in the solution, and the adsorption extraction chamber 2 was connected to the fixed bottle cap 1 fixed with the molecular imprinting solid phase microextraction fiber 3 through an external thread, and the assembly of the combined device was completed after sealing;

[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 ethyl paraben using a device containing a molecularly imprinted adsorption extraction stirring rod, comprising the following steps:

[0072] (1) using the method of step (1) of Example 2 to prepare a molecularly imprinted adsorption extraction stirring bar 4 of ethyl paraben;

[0073] (2) 50 mL of 100 μg / L ethyl paraben solution was loaded into the adsorption extraction chamber 2, the molecular imprinting adsorption extraction stirring rod 4 was placed at the bottom of the adsorption extraction chamber 2, the adsorption extraction chamber 2 was connected to the fixed bottle cap 1 through an external thread, and the device was assembled after sealing;

[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 using a device containing a molecularly imprinted solid phase microextraction fiber, comprising the following steps:

[0077] (1) The method of step (1) of Example 2 was used to prepare molecularly imprinted solid phase microextraction fiber 3 of ethyl paraben;

[0078] (2) 50 mL of 100 μg / L ethyl paraben solution was loaded into the adsorption extraction chamber 2, the molecular imprinted solid phase microextraction fiber 3 was fixed with the fixed bottle cap 1, the adsorption coating of the molecular imprinted solid phase microextraction fiber 3 was adjusted to be completely immersed in the solution, the adsorption extraction chamber 2 was connected to the fixed bottle cap 1 fixed with the molecular imprinted solid phase microextraction fiber 3 through the external thread, and the device was assembled after sealing;

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

[0080] Test Example 2

[0081] (1) The molecular imprinted solid phase microextraction fiber 3 and the molecular imprinted adsorption extraction stirring rod 4 after the extraction in Example 2, the molecular imprinted adsorption extraction stirring rod 4 after the extraction in Comparative Example 3, and the molecular imprinted solid phase microextraction fiber 3 after the extraction in Comparative Example 4 were taken out, and ultrasonically desorbed with 200 μL of methanol for 10 min respectively;

[0082] (2) The three desorbents were analyzed by HPLC. The conditions of HPLC were as follows: a C18 column, a mobile phase of acetonitrile / water (50:50, v / v), a column temperature of 30°C, a flow rate of 1 mL / min, and dual-wavelength detection at wavelengths of 225 nm and 254 nm.

[0083] The peak areas of the analytical solutions obtained under the three extraction conditions of Example 2 and Comparative Examples 3 to 4 were analyzed. The results are as follows: Figure 3 shown. Figure 3 The results show that the peak area of ​​ethylparaben extracted by Example 2 is 7.94 mAU·min, and the peak areas of ethylparaben extracted by Comparative Example 4 or Comparative Example 3 are 4.32 mAU·min and 4.77 mAU·min, respectively. Therefore, compared with the scheme using a single extraction fiber or a single extraction stirring rod, the peak area of ​​ethylparaben extracted by the combined device of the present invention is 1.84 times that of a single extraction fiber and 1.67 times that of a single extraction stirring rod, which indicates that the extraction efficiency of the combined device is significantly higher than that of a single extraction method.

[0084] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A combined device of solid phase microextraction fiber and adsorption extraction stirring rod, characterized in that: It 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 by threads.

2. The combined device according to claim 1, characterized in that: The fixed bottle cap (1) is filled with fixing material.

3. The combined device according to claim 2, characterized in that: The fixing material includes a rubber gasket.

4. The combined device 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 combined device according to claim 4, characterized in that: The length of the adsorption extraction stirring rod (4) is smaller than the inner diameter of the bottom of the adsorption extraction chamber (2).

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

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

8. The method for using the combined device according to any one of claims 1 to 7, characterized in that: The method of use comprises the following steps: adding the liquid phase to be extracted into the adsorption extraction chamber (2); placing the solid phase microextraction fiber (3) and the adsorption extraction stirring rod (4) into the liquid phase to be extracted at the same time, threading the fixed bottle cap (1) and the adsorption extraction chamber (2), assembling the combined device, and performing extraction; Alternatively, the method of use comprises 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, and simultaneously placing the adsorption extraction stirring rod (4) into the liquid phase to be extracted, threading the fixed bottle cap (1) and the adsorption extraction chamber (2), assembling the combined device, and performing extraction.

9. The method of use according to claim 8, characterized in that: The combined device during the extraction is airtight.

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