Method for detecting perfluorinated and polyfluoroalkyl compounds in plasma

Abstract

The invention belongs to the field of plasma detection, and particularly relates to a method for detecting perfluoro and polyfluoroalkyl compounds in plasma. Comprising the following steps: extracting target perfluoro and polyfluoroalkyl compounds in plasma by adopting an ion pair extraction method: mixing the plasma with a buffer solution, adding a tetrabutylammonium hydrogen sulfate solution, uniformly mixing, adding an isotope labeling mixed solution as an internal standard, then adding methyl tert-butyl ether, centrifugally sucking supernate after vortex oscillation, repeatedly extracting, and collecting the target perfluoro and polyfluoroalkyl compounds in the plasma. Combining the supernate, blow-drying, and redissolving with a methanol solution to obtain a to-be-detected sample; detecting a to-be-detected sample through a liquid chromatography-quadrupole time-of-flight high-resolution mass spectrometry method; and analyzing the data to obtain the types and concentrations of the target perfluorinated and polyfluoroalkyl compounds. The method has the advantages of simplicity and convenience in sample treatment, short detection time, high resolution, high sensitivity and the like, and the concentration of trace PFASs in plasma can be efficiently, accurately and quantitatively analyzed.

Description

Technical Field

[0001] The present invention belongs to the field of plasma detection, and particularly relates to a method for detecting perfluoro- and polyfluoroalkyl substances in plasma. Background Art

[0002] Perfluoro- and polyfluoroalkyl substances (PFASs) are a class of organic compounds with persistence, bioaccumulation, and potential toxicity. They have been widely used in industrial and consumer products, such as non-stick pan coatings, waterproof and stain-resistant fabrics, and food packaging materials. Due to their strong chemical stability and resistance to degradation, PFASs can persist in the environment for a long time and accumulate in organisms through biomagnification in the food chain. In recent years, the environmental pollution problem of PFASs has attracted widespread global attention, and their associations with various health problems have gradually been revealed, including liver toxicity, immune function alteration, thyroid function abnormalities, and cancer. Therefore, monitoring PFASs in biological matrices is of great significance for evaluating the risk of adverse health effects and preventing disease occurrence.

[0003] PFASs have a long biological half-life and relatively stable concentrations in plasma, which can reflect long-term exposure. Therefore, regularly collecting and accurately detecting the exposure levels of PFASs in plasma samples is of great value in long-term monitoring and trend analysis. However, due to the physical and chemical properties of PFASs, they often exist at trace levels in various environmental and biological matrices, which further increases the complexity of detection and analysis. Although traditional triple quadrupole mass spectrometry detection methods can provide certain detection sensitivity and accuracy, they often have problems such as cumbersome sample processing, long detection time, and insufficient resolution when facing complex biological samples (such as plasma). Therefore, developing a simpler, more sensitive, and accurate plasma PFASs detection method is crucial for evaluating human exposure levels and studying the health risks of PFASs. The development of high-resolution mass spectrometry technology has provided diverse possibilities for identifying PFASs exposure. As an emerging detection and analysis technology, UHPLC-Q-TOF-MS combines the high separation ability of ultra-high performance liquid chromatography and the high sensitivity and high resolution of quadrupole time-of-flight high-resolution mass spectrometry, and can effectively overcome the limitations of traditional methods. Based on UHPLC-Q-TOF-MS, the present invention has developed a quantitative detection technology for detecting the exposure levels of PFASs in plasma samples (complex matrices) at trace levels. This technology can efficiently and accurately quantify the concentrations of various PFASs in plasma, providing a new solution for fields such as environmental monitoring, toxicological research, and human exposure assessment of PFASs. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide an analytical method for detecting the concentrations of 21 perfluoro and polyfluoroalkyl substances (PFASs) in plasma based on ultra-high performance liquid chromatography tandem quadrupole time-of-flight high-resolution mass spectrometry (UHPLC-Q-TOF-MS) in view of the deficiencies of the prior art. This method combines ion-pair extraction sample pretreatment technology, chromatography-mass spectrometry combined detection technology, and multiple isotope internal standard quantitative analysis technology to achieve high-throughput detection of multiple PFASs in complex matrices (such as plasma). This method has the advantages of simple sample treatment, short detection time, high resolution, and strong sensitivity, and can efficiently and accurately quantify the concentrations of trace PFASs in plasma, providing reliable technical support and innovative solutions for fields such as PFASs environmental monitoring, toxicological research, and human exposure risk assessment.

[0005] To solve the above technical problem, the present invention discloses a method for detecting perfluoro and polyfluoroalkyl compounds in plasma, comprising the following steps:

[0006] S1. Extract the target perfluoro and polyfluoroalkyl compounds in plasma by ion-pair extraction: Mix plasma with a buffer solution, add tetrabutylammonium hydrogen sulfate solution and mix well, then add an isotope-labeled mixed solution as an internal standard, and then add methyl tert-butyl ether. After vortex oscillation, centrifuge and aspirate the supernatant. Repeat the extraction, combine the supernatants, dry them, and re-dissolve them with a methanol solution to obtain the sample to be tested;

[0007] S2. Detect the sample to be tested by ultra-high performance liquid chromatography tandem quadrupole time-of-flight high-resolution mass spectrometry;

[0008] S3. Analyze the data to obtain the types and concentrations of the target perfluoro and polyfluoroalkyl compounds.

[0009] Among them, the perfluoro and polyfluoroalkyl compounds include any one or several of perfluorobutyric acid, perfluoropentanoic acid, perfluorohexanoic acid, perfluoroheptanoic acid, perfluorooctanoic acid, perfluorononanoic acid, perfluorodecanoic acid, perfluoroundecanoic acid, perfluorododecanoic acid, perfluorotridecanoic acid, perfluorotetradecanoic acid, perfluorobutanesulfonic acid, perfluoropentanesulfonic acid, perfluorohexanesulfonic acid, perfluorooctanesulfonic acid, perfluorononanesulfonic acid, perfluorodecanesulfonic acid, hexafluoropropylene oxide dimer carboxylic acid, dodecafluoro-3H-4,8-dioxanonanoic acid, 6:2 chlorinated polyfluoroalkyl ether sulfonic acid, and 8:2 chlorinated polyfluoroalkyl ether sulfonic acid.

[0010] Among them, in S1, the volume ratio of the plasma to the buffer solution is 1:10; the volume ratio of the plasma to the tetrabutylammonium hydrogen sulfate solution is 1:5; the volume ratio of the plasma to the isotope-labeled mixed solution is 10:1; the volume ratio of the plasma to the methyl tert-butyl ether is 1:20;

[0011] Specifically, the buffer solution is Na 2 CO3 and NaHCO 3 mixed solution, wherein the concentration of Na 2 CO 3 is 0.25 mol / L, and the concentration of NaHCO 3 is 0.25 mol / L; the concentration of tetrabutylammonium hydrogensulfate solution is 0.50 mol / L; the concentration of the isotope-labeled mixed solution is 25.0 ng / mL.

[0012] Among them, in S1, the volume ratio of the plasma to the methanol solution is 1:1; the concentration of the methanol solution is 70% (v / v).

[0013] Among them, in S2, for the liquid chromatography, the chromatographic column is a C18 chromatographic column, the mobile phase includes mobile phase A and mobile phase B, the flow rate is 0.3 mL / min, and the column temperature is 40°C;

[0014] Specifically, the mobile phase A is a 10 mM ammonium acetate solution; the mobile phase B is pure acetonitrile.

[0015] Specifically, the elution method used in the liquid chromatography is gradient elution, and the specific elution procedure is as follows:

[0016] Time (min) A％ B％ 0～ 80 20 8～ 5 95 10～ 5 95 10.75～ 80 20 14 80 20 .

[0017] Among them, in S2, for the mass spectrometry, the ion source mode is negative ion electrospray ionization and multiple reaction monitoring mode, the ion source temperature is 500°C, the pressure of ion source gas 1 is 50 psi, the pressure of ion source gas 2 is 50 psi, the pressure of curtain gas is 35 psi, the pressure of collision gas is 8 psi, the ionization temperature is 500°C, the spray voltage is -4500 V, and the scanning range is m / z 100 - 1000.

[0018] Among them, in S3, the analysis includes qualitative analysis and quantitative analysis. Qualitative analysis determines the target peak by determining the retention time and area of the parent ion and daughter ion chromatographic peaks in the sample to be tested, thereby determining the corresponding perfluoro- and polyfluoroalkyl compounds. The time difference between the retention time of the analyte and that of the corresponding standard should not exceed 30 s; quantitative analysis is achieved by the ratio of the chromatographic peak area of the daughter ion in the sample to be tested to the chromatographic peak area of the daughter ion of the corresponding internal standard, and the quantitative analysis of perfluoro- and polyfluoroalkyl compounds is realized by the internal standard curve method.

[0019] Beneficial effects:

[0020] The method provided by the present invention for detecting the concentrations of 21 PFASs in plasma based on ultra-high performance liquid chromatography tandem quadrupole time-of-flight high-resolution mass spectrometry has the characteristics of high sensitivity, high accuracy, high throughput, wide application range and simple operation. It can meet the need for accurate detection of trace PFASs. The method can simultaneously detect a variety of traditional and new PFASs, taking into account both long-chain and short-chain PFASs, and is suitable for rapid detection of a large number of samples, providing reliable technical support for comprehensively evaluating the human PFASs exposure level. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The following further specifically describes the present invention in conjunction with the drawings and specific embodiments, and the above and / or other advantages of the present invention will become clearer.

[0022] Figure 1 It is the mass spectrometry result diagram for detecting 21 PFASs in the embodiment of the present invention. Among them, A is the total ion current chromatogram of the plasma sample after pretreatment and loading, and B is the chromatogram of the target PFASs and the corresponding internal standards. SPECIFIC EMBODIMENTS

[0023] In the following experimental methods described in the embodiments, unless otherwise specified, they are all conventional methods; the reagents and materials, unless otherwise specified, can all be obtained from commercial channels.

[0024] Example 1:

[0025] A method for detecting per- and polyfluoroalkyl compounds in plasma, specifically, includes the following steps:

[0026] S1. Sample pretreatment:

[0027] (1) Using the ion pair extraction method, thaw the plasma sample stored in an ultra-low temperature refrigerator overnight in a 4°C refrigerator. Accurately pipette 200 μL of the plasma sample into a clean 15 mL centrifuge tube, and add 2 mL of a mixed solution composed of 0.25 mol / L Na 2 CO 3 and 0.25 mol / L NaHCO 3 as a buffer solution, add 1 mL of 0.50 mol / L tetrabutylammonium hydrogen sulfate solution to improve the extraction efficiency, add 20 μL of a 25.0 ng / mL isotope-labeled mixed solution as an internal standard, add 4 mL of methyl tert-butyl ether, vortex at 250 rpm for 10 min to fully extract the target per- and polyfluoroalkyl substances (PFASs), centrifuge at 4000 rpm for 10 min at 4°C, and then pipette the supernatant. Repeat the above extraction steps and combine the supernatants of the two times in a centrifuge tube;

[0028] (2) Use a nitrogen evaporator in the fume hood to dry the combined supernatant (about 8 mL) at 40 °C; adjust the nitrogen flow rate to 2 L / min, and continuously adjust to keep the distance between the nitrogen nozzle and the sample surface at about 1 - 2 cm to ensure complete evaporation of the solvent until it is completely dried.

[0029] (3) Dilute the dried centrifuge tube to a fixed volume with 200 μL of 70% methanol solution, vortex for 1 min, and let it stand at 4 °C for 30 min; centrifuge at 4000 rpm for 5 min at 4 °C. After centrifugation, aspirate the supernatant and centrifuge it through a 0.22 μm filter column into an autosampler vial.

[0030] S2. Sample detection:

[0031] Analyze the pretreated sample using Ultra-High Performance Liquid Chromatography-Quadrupole Time-of-Flight Mass Spectrometry (UHPLC-QTOF-MS).

[0032] Among them, the 21 target substances in plasma include: perfluorobutyric acid (PFBA), perfluoropentanoic acid (PFPeA), perfluorohexanoic acid (PFHxA), perfluoroheptanoic acid (PFHpA), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUnDA), perfluorododecanoic acid (PFDoA), perfluorotridecanoic acid (PFTrDA), perfluorotetradecanoic acid (PFTeDA), perfluorobutane sulfonic acid (PFBS), perfluoropentane sulfonic acid (PFPeS), perfluorohexane sulfonic acid (PFHxS), perfluorooctane sulfonic acid (PFOS), perfluorononane sulfonic acid (PFNS), perfluorodecane sulfonic acid (PFDS), hexafluoropropylene oxide dimer carboxylic acid (HFPO-DA), dodecafluoro-3H-4,8-dioxanonanoic acid (DONA), 6:2 chlorinated polyfluoroalkyl ether sulfonic acid (6:2Cl-PFESA), 8:2 chlorinated polyfluoroalkyl ether sulfonic acid (8:2Cl-PFESA);

[0033] The internal standard compounds corresponding to 21 target substances include: 13C isotope-labeled perfluorobutyric acid (M4PFBA), 13C isotope-labeled perfluoropentanoic acid (M5PFPeA), 13C isotope-labeled perfluorohexanoic acid (M5PFHxA), 13C isotope-labeled perfluoroheptanoic acid (M4PFHpA), 13C isotope-labeled perfluorooctanoic acid (M8PFOA), 13C isotope-labeled perfluorononanoic acid (M9PFNA), 13C isotope-labeled perfluorodecanoic acid (M6PFDA), 13C isotope-labeled perfluoroundecanoic acid (M7PFUnDA), 13C isotope-labeled perfluorododecanoic acid (M2PFDoA), 13C isotope-labeled perfluorotetradecanoic acid (M2PFTeDA), 13C isotope-labeled perfluorobutanesulfonic acid (M3PFBS), 13C isotope-labeled perfluorohexanesulfonic acid (M3PFHxS), 13C isotope-labeled perfluorooctanesulfonic acid (M8PFOS). Table 1 shows the full names, abbreviations, CAS numbers of 21 PFASs and their corresponding internal standards.

[0034] Table 1 Full names, abbreviations, CAS numbers of 21 PFASs and their corresponding internal standards

[0035]

[0036]

[0037] The liquid chromatograph used is AB Sciex ExionLC TM AC. The conditions for liquid chromatography are as follows: Chromatographic column: Waters Acquity UPLC BEH C18 (2.1 mm × 100 mm, 1.7 μm); Mobile phase: Phase A is 10 mM ammonium acetate solution, Phase B is pure acetonitrile solution; Flow rate: 0.3 mL / min; Column temperature: 40 °C; Injection volume: 10 μL; The gradient elution program is shown in Table 2.

[0038] Table 2 Gradient elution program

[0039] Time (min) A% (10 mmol / L ammonium acetate solution) B% (acetonitrile) 0～ 80 20 8～ 5 95 10～ 5 95 10.75～ 80 20 14 80 20

[0040] The mass spectrometer used was an AB Sciex X500R QTOF, and the mass spectrometry conditions were as follows: Negative ion electrospray ionization and multiple reaction monitoring (MRM) mode were adopted. The ion source parameters of the mass spectrometry conditions were set as follows: Ion source temperature: 500 °C; Ion source gas 1: 50 psi; Ion source gas 2: 50 psi; Curtain gas: 35 psi; Collision gas: 8 psi; Ionization temperature: 500 °C; Spray voltage (IS): -4500 V; Scanning range: m / z 100 - 1000; The parent ions, daughter ions, declustering voltages, collision energies, and retention times of 21 PFASs are shown in Table 3.

[0041] Table 3 Parent ions, daughter ions, declustering voltages, collision energies, and retention times of 21 PFASs

[0042]

[0043]

[0044] The mass spectrometry results of detecting 21 PFASs by the method of the present invention are as Figure 1 shown, where Figure 1 A in Figure 1 is the total ion current chromatogram of the plasma sample after pretreatment and loading, Figure 1 and B in Figure 1 are the chromatographic peaks of the target PFASs and the corresponding internal standards. Under the method conditions provided by the present invention, the total ion current chromatogram of the plasma sample was detected (see

[0045] Method validation:

[0046] Establishment of the standard curve: The internal standard standard curve method was selected for relative quantitative analysis. Standard series solutions of 21 PFASs were prepared to cover their linear ranges (Table 4). A total of 9 gradient concentrations of 0.05, 0.1, 0.25, 0.5, 1, 2.5, 5, 10, and 25.0 ng / mL were set. For each concentration gradient, 0.5 ng of the corresponding isotope-labeled internal standard was added. Using the exact same pretreatment process, analysis was carried out by chromatography and mass spectrometry under the same conditions. Each concentration was detected three times and the average value was taken. With the concentration as the abscissa and the ratio of the chromatographic peak area of the standard analyte to the chromatographic peak area of the corresponding internal standard as the ordinate, the standard curve was plotted by the least squares method. The results are shown in Table 4.

[0047] Confirmation of the limit of detection and the lower limit of quantification: The limit of detection (LOD) and the lower limit of quantification (LOQ) of each PFAS were confirmed by the signal-to-noise ratio of each PFAS at a concentration gradient of 1 ng / mL (isotope-labeled internal standard corresponding to 0.5 ng) during the standard curve plotting process. The limit of detection is the lowest concentration at which the analyte can be detected and is defined as three times the signal-to-noise ratio (S / N); the lower limit of quantification is the lowest concentration at which the analyte can be accurately quantified and is defined as 10 times the signal-to-noise ratio.

[0048] The results are shown in Table 4. The 21 PFASs had good linearity in the range of 0.01 - 25.0 ng / mL, and the correlation coefficient (R 2 ) > 0.99; the LOD of the 21 PFASs was 0.001 - 0.039 ng / mL, and the LOQ was 0.003 - 0.131 ng / mL, indicating that the method of the present invention can meet the detection of 21 PFAS compounds in plasma clinically.

[0049] Table 4 Standard curves, limits of detection and lower limits of quantification of 21 PFASs

[0050]

[0051] Qualitative and quantitative analysis of the target substance: The target peak was determined based on the retention time and area of the chromatographic peaks of the analyte parent ion and daughter ion in the ion scan results of the actual sample, thereby realizing the qualitative analysis of the target substance. During the analysis process, the time difference between the retention time of the analyte and the corresponding standard should not exceed 30 s. By calculating the ratio of the chromatographic peak area of the daughter ion in the ion scan results of the actual sample to the chromatographic peak area of the daughter ion of the corresponding internal standard, the relative quantitative analysis of the target substance was realized by the internal standard standard curve method. The concentration of the target substance below the lower limit of quantification was calculated as the lower limit of quantification divided by √2.

[0052] Analysis of accuracy and precision: The matrix spike method was used to determine the spike recovery rates of 21 PFASs to evaluate the sensitivity and accuracy of the detection method. Blank fetal bovine plasma samples were selected to prepare PFAS standard solutions at four concentrations of 0.1 ng / mL, 1.0 ng / mL, 2.0 ng / mL, and 5 ng / mL, with 3 replicate samples set for each concentration, and each sample was detected three times. According to the standard curve, the average value of the difference between the measured concentration and the sample itself concentration was calculated, and the recovery rate of PFASs was obtained by comparing with the sample itself concentration.

[0053] The results are shown in Table 5. The recovery rates of the 21 PFASs at the four spike concentrations were between 75.8% and 128.5%, and the relative standard deviations were between 0.4% and 14.8%, indicating that the method of the present invention has good accuracy and precision.

[0054] Recovery rates of 21 PFASs in Table 5

[0055]

[0056] Example 2:

[0057] 390 plasma samples from hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) patients (HBV-HCC) in the Affiliated Tumor Hospital of Guangxi Medical University and 390 plasma samples from chronic hepatitis B (CHB) patients in the Wuming Hospital Affiliated to Guangxi Medical University, the First People's Hospital of Qinzhou City, and the Liuzhou Workers' Hospital were collected and stored at -80 °C for later use.

[0058] The 780 plasma samples were pretreated and analyzed by UHPLC-QTOF-MS according to the detection method provided in Example 1.

[0059] During the detection process, 30 plasma samples were randomly selected to prepare a mixed blood sample as a quality control sample. During the detection of the same batch of samples, 200 μL of the mixed blood sample was taken and processed in parallel according to the method provided in the present invention. A quality control sample was set for every 20 plasma samples detected to investigate the precision and accuracy of the within-batch detection. At the same time, a blank sample (70% methanol solution) was set for every 10 plasma samples detected to evaluate the background contamination of the instrument.

[0060] The detection results of the quality control samples indicated that the detection results of 21 PFASs were reliable, with the relative standard deviation ranging from 2.5% to 10.7%. The detection results of the blank samples did not indicate background contamination of the instrument. Table 6 shows the median concentration detection rates of 21 PFASs in 780 plasma samples. As can be seen from the table, 19 PFASs were detected in 780 plasma samples. The detection rates of PFBA, PFHpA, PFOA, PFNA, PFDA, PFUnDA, PFPeS, PFHxS, PFOS, and 6:2Cl-PFESA were all above 90%, indicating that humans are exposed to a mixture of multiple PFASs.

[0061] Table 6 Median concentration detection rates of 21 PFASs in 780 plasma samples

[0062]

[0063] The present invention provides a method for detecting perfluoro- and polyfluoroalkyl substances in plasma. There are many methods and ways to specifically implement this technical solution. The above description is only the preferred embodiment of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention. Each component not clearly defined in this embodiment can be implemented by existing technologies.

Claims

1. A method for detecting perfluoroalkyl and polyfluoroalkyl compounds in plasma, characterized in that: The steps include: S1. Extract the target perfluorinated and polyfluorinated alkyl compounds in plasma by ion pair extraction: mix the plasma with buffer, add tetrabutylammonium hydrogen sulfate solution and mix well, then add isotope labeled mixed solution as internal standard, then add methyl tert-butyl ether, vortex and centrifuge to absorb the supernatant, repeat the above extraction steps, combine the supernatants, blow dry and re-dissolve with methanol solution to obtain the sample to be tested; S2. Detect the sample by liquid chromatography-tandem quadrupole time-of-flight high-resolution mass spectrometry; S3. Analyze the data to obtain the types and concentrations of target perfluoroalkyl and polyfluoroalkyl compounds.

2. The method according to claim 1, characterized in that The perfluoro and polyfluoroalkyl compounds include any one or more of perfluorobutyric acid, perfluoropentanoic acid, perfluorohexanoic acid, perfluoroheptanoic acid, perfluorooctanoic acid, perfluorononanoic acid, perfluorodecanoic acid, perfluoroundecanoic acid, perfluorododecanoic acid, perfluorotridecanoic acid, perfluorotetradecanoic acid, perfluorobutane sulfonic acid, perfluoropentane sulfonic acid, perfluorohexane sulfonic acid, perfluorooctane sulfonic acid, perfluorononane sulfonic acid, perfluorodecane sulfonic acid, hexafluoropropylene oxide dimer carboxylic acid, dodecafluoro-3H-4,8-dioxanononanoic acid, 6:2 chlorinated polyfluoroalkyl ether sulfonic acid and 8:2 chlorinated polyfluoroalkyl ether sulfonic acid.

3. The method according to claim 1, characterized in that In S1, the volume ratio of the plasma to the buffer solution is 1:10; the volume ratio of the plasma to the tetrabutylammonium hydrogen sulfate solution is 1:5; the volume ratio of the plasma to the isotope-labeled mixed solution is 10:1; and the volume ratio of the plasma to methyl tert-butyl ether is 1:

20.

4. The method according to claim 3, characterized in that The buffer solution is a mixed solution of Na2CO3 and NaHCO3, the concentration of Na2CO3 is 0.25 mol / L, the concentration of NaHCO3 is 0.25 mol / L; the concentration of tetrabutylammonium hydrogen sulfate solution is 0.50 mol / L; the concentration of the isotope-labeled mixed solution is 25.0 ng / mL.

5. The method according to claim 1, characterized in that In S1, the volume ratio of the plasma to the methanol solution is 1:1; the concentration of the methanol solution is 70% (v / v).

6. The method according to claim 1, characterized in that In S2, the liquid chromatography has a C18 chromatographic column, the mobile phases include mobile phase A and mobile phase B, the flow rate is 0.3 mL / min, and the column temperature is 40°C.

7. The method according to claim 6, characterized in that The mobile phase A is 10 mM ammonium acetate solution; the mobile phase B is pure acetonitrile.

8. The method according to claim 6, characterized in that The elution method adopted by the liquid chromatography is gradient elution, and the specific elution procedure is as follows:

9. The method according to claim 1, characterized in that: In S2, the mass spectrometer has an ion source mode of negative ion electrospray ionization and multiple reaction monitoring mode, an ion source temperature of 500°C, an ion source gas 1 pressure of 50psi, an ion source gas 2 pressure of 50psi, a curtain gas pressure of 35psi, a collision gas pressure of 8psi, an ionization temperature of 500°C, a spray voltage of -4500V, and a scanning range of m / z 100 to 1000.

10. The method according to claim 1, characterized in that In S3, the analysis includes qualitative analysis and quantitative analysis. The qualitative analysis determines the target peak by the retention time and area of ​​the parent ion and daughter ion chromatographic peaks in the test sample to determine the corresponding perfluoroalkyl and polyfluoroalkyl compounds. The retention time difference between the test object and the corresponding standard should not exceed 30s. The quantitative analysis is achieved by the ratio of the chromatographic peak area of ​​the daughter ion in the test sample to the chromatographic peak area of ​​the daughter ion of the corresponding internal standard through the internal standard curve method.

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