A method for detecting perfluorinated and polyfluorinated compounds in cerebrospinal fluid

Abstract

The present invention discloses a method for detecting perfluorinated and polyfluorinated compounds in cerebrospinal fluid. Liquid chromatography tandem mass spectrometry is used for detection, mobile phase A is methanol, mobile phase B is ammonium acetate aqueous solution, gradient elution, and the cerebrospinal fluid to be tested is directly tested on the machine, without the need for a complicated pre-treatment process, and the 27 perfluorinated and polyfluorinated compounds tested can have a high recovery rate, a spiked recovery rate between 77.9% and 101.3%, a relative deviation of less than 20%, and a wide coverage range, including 27 perfluorinated sulfonic acids, perfluorooctanoic acids and other perfluorinated compounds; high sensitivity, 27 perfluorinated compounds can all meet the pg-level detection requirements; high efficiency, good repeatability, high recovery rate, and simultaneous determination of 27 perfluorinated compounds only takes 8 minutes.

Description

Technical Field

[0001] The present invention relates to the technical field of analysis and detection, and in particular to a method for detecting perfluorinated and polyfluorinated compounds in cerebrospinal fluid. Background Art

[0002] Perfluorinated and polyfluorinated compounds (PFAS) are man-made chemicals that have been used in industrial and consumer products since 1940 due to their waterproof and oil-proof properties. They are widely used in non-stick coatings, surfactants, food packaging materials, fire-fighting foams, etc., so it is difficult for the human body to avoid exposure to PFAS pollution. Occupations related to PFAS processing and manufacturing applications, drinking water contaminated by PFAS, food containing PFAS, soil or dust contaminated by PFAS, air containing PFAS, products made of PFAS or packaged with materials containing PFAS, etc. may all be sources of PFAS pollution. PFAS compounds are persistent, which leads to their widespread presence in the environment. It is also bioaccumulative and can bring a variety of adverse and lasting effects on organisms. In addition to causing damage to the liver, it can also have significant adverse effects on the immune system and endocrine and reproductive systems. Recently, the relevant departments issued the "List of New Pollutants for Key Control (2023 Edition)", and perfluorooctane sulfonic acid and its salts and perfluorooctane sulfonyl fluoride, perfluorooctanoic acid and its salts and related compounds were included in the list of new pollutants for key control.

[0003] Cerebrospinal fluid is close to the human brain, and exposure to pollutants in cerebrospinal fluid has a significant impact on human health, but there is currently a lack of methods to detect perfluorinated compounds in cerebrospinal fluid. Cerebrospinal fluid is a colorless, transparent liquid present in the ventricles and subarachnoid space. It has a high degree of purity and low levels of protein and lipids. It is a special body fluid. Currently, there are few liquid phase detection methods specifically for compounds in cerebrospinal fluid, and all require complex pre-treatment of the cerebrospinal fluid before testing on the machine, which affects the recovery rate and accuracy, and the steps are complicated. In order to further explore the impact of human exposure to PFAS on cerebrospinal fluid, a simple, fast, and accurate method for detecting multiple PFAS in a special matrix of cerebrospinal fluid is needed. Summary of the invention

[0004] The object of the present invention is to overcome the above-mentioned deficiencies of the prior art and to provide a method for detecting perfluorinated and polyfluorinated compounds in cerebrospinal fluid.

[0005] In order to achieve the above object, the present invention is implemented by the following scheme:

[0006] A method for detecting perfluorinated and polyfluorinated compounds in cerebrospinal fluid, characterized in that the detection is performed by liquid chromatography tandem mass spectrometry, the mobile phase A is methanol, the mobile phase B is ammonium acetate aqueous solution, and the gradient elution is performed.

[0007] 0-1min, the volume ratio of mobile phase A to mobile phase B was 20:80;

[0008] From 1 to 4 min, the volume ratio of mobile phase A to mobile phase B changed from 20:80 to 95:5;

[0009] 4-6.5 min, the volume ratio of mobile phase A to mobile phase B was 95:5;

[0010] From 6.5 to 6.6 min, the volume ratio of mobile phase A to mobile phase B changed from 95:5 to 20:80;

[0011] 6.6~8min, the volume ratio of mobile phase A to mobile phase B is 20:80.

[0012] Preferably, after adding isotope-labeled internal standards corresponding to perfluorinated and polyfluorinated compounds to the cerebrospinal fluid sample to be tested, the detection method is directly used for detection.

[0013] Preferably, the perfluoro and polyfluoro compounds are perfluorobutyric acid, perfluoropentanoic acid, perfluorohexanoic acid, perfluoroheptanoic acid, perfluorooctanoic acid, perfluorononanoic acid, perfluorodecanoic acid, perfluoroundecanoic acid, perfluorododecanoic acid, perfluorotridecanoic acid, perfluorotetradecanoic acid, perfluorobutylsulfonamide, perfluorohexylsulfonamide, perfluorooctylsulfonamide, perfluoro 2-methyl-3-oxahexanoic acid, N-methyl perfluorooctane aminoacetic acid, N-ethyl perfluorooctane aminoacetic acid, perfluorobutylsulfonic acid, perfluoropentanesulfonic acid, perfluorohexanesulfonic acid, One or more of the group consisting of 1H,1H,2H,2H-perfluorohexyl sulfonic acid, 1H,1H,2H,2H-perfluorooctane sulfonic acid, 1H,1H,2H,2H-perfluorodecane sulfonic acid, 4,8-dioxo-3H-perfluorononanoic acid ethyl ester and 2-[(6-chloro-1,1,2,2,3,3,4,4,5,5,6,6-dodecafluorohexyl)oxy]-1,1,2,2-tetrafluoroethane sulfonic acid.

[0014] More preferably, the isotope-labeled internal standard is 13 C 4 -PFBA, 13 C 5 -PFPeA, 13 C 5 -PFHxA, 13 C 4 -PFHpA, 13 C 8 -PFOA, 13 C 9 -PFNA, 13 C 6 -PFDA, 13 C 7 -PFUdA, 13 C2 -PFDoA, 13 C 2 -PFTeDA, 13 C 3 -PFBS, 13 C 3 -PFHxS, 13 C 8 -PFOS, D 3 -N-MeFOSAA, D 5 -N-EtFOSAA, 13 C 2 -4:2FTS, 13 C 2 -6:2FTS and 13 C 2 -8:2FTS one or more.

[0015] Preferably, the concentration of ammonium acetate is 1.9-2.1 mM.

[0016] More preferably, the concentration of ammonium acetate is 2 mM.

[0017] Preferably, the flow rate of gradient elution is 0.29-0.31 mL / min.

[0018] More preferably, the flow rate of gradient elution is 0.3 mL / min.

[0019] Preferably, the detection column temperature is 39-41°C.

[0020] More preferably, the detection column temperature is 40°C.

[0021] Preferably, the chromatographic column is a Waters BEH C18 high performance liquid chromatography column, the length of the chromatographic column is 100 mm, the inner diameter is 2.1 mm, and the filler particle diameter is 1.7 μm.

[0022] Preferably, the mass spectrometry conditions are: curtain gas 40 psi, ionization voltage -4500 V, temperature 500° C., spray gas 50 psi, auxiliary heating gas 50 psi, collision gas medium.

[0023] Preferably, the liquid chromatograph used is a Shimadzu 20AD high performance liquid chromatography system, and the mass spectrometer is an AB Sciex QTRAP 5500 electrospray triple quadrupole mass spectrometer.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] The present invention combines the properties of cerebrospinal fluid and develops a fast, efficient and low-cost direct injection method for detecting 27 perfluorinated compounds in cerebrospinal fluid. The present invention directly detects cerebrospinal fluid on the machine without complicated pre-treatment process, and can also make the 27 perfluorinated and polyfluorinated compounds detected have high recovery rate, the spike recovery rate is between 77.9% and 101.3%, the relative deviation is less than 20%, and the coverage is wide, including 27 perfluorinated sulfonic acids, perfluorooctanoic acids and other perfluorinated compounds; high sensitivity, 27 perfluorinated compounds can meet the pg level detection requirements; high efficiency, good repeatability, high recovery rate, and simultaneous determination of 27 perfluorinated compounds only takes 8 minutes. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is the chromatogram of perfluorobutanoic acid (PFBA).

[0027] Figure 2 This is the chromatogram of perfluoropentanoic acid (PFPeA).

[0028] Figure 3 This is the chromatogram of perfluorohexanoic acid (PFHxA).

[0029] Figure 4 This is the chromatogram of perfluoroheptanoic acid (PFHpA).

[0030] Figure 5 This is the chromatogram of perfluorooctanoic acid (PFOA).

[0031] Figure 6 This is the chromatogram of perfluoro-n-nonanoic acid (PFNA).

[0032] Figure 7 This is the chromatogram of perfluorodecanoic acid (PFDA).

[0033] Figure 8 This is the chromatogram of perfluoro-n-undecanoic acid (PFUdA).

[0034] Fig. 9 This is the chromatogram of perfluoro-n-dodecanoic acid (PFDoA).

[0035] Fig.10 This is the chromatogram of perfluoro-n-tridecanoic acid (PFTrDA).

[0036] Fig.11 This is the chromatogram of perfluoro-n-tetradecanoic acid (PFTeDA).

[0037] Fig.12 This is the chromatogram of perfluoro-1-butanesulfonamide (FBSA).

[0038] Fig.13 This is the chromatogram of perfluoro-1-hexanesulfonamide (FHxSA).

[0039] Fig.14 This is the chromatogram of perfluoro-1-octanesulfonamide (FOSA).

[0040] Fig.15 This is the chromatogram of perfluoro-2-methyl-3-oxahexanoic acid (2,3,3,3-Tetrafluoro-2-(1,1,2,2,3,3,3-heptafluoropropoxy)-propanoic acid, HFPO-DA).

[0041] Fig.16 This is the chromatogram of N-methylperfluoro-1-octanesulfonamidoacetic (N-MeFOSAA).

[0042] Fig.17 This is the chromatogram of N-ethylperfluoro-1-octanesulfonamidoacetic (N-EtFOSAA).

[0043] Fig.18 This is the chromatogram of perfluorobutanesulfonate (PFBS).

[0044] Fig.19 This is the chromatogram of perfluoropentanesulfonate (PFPeS).

[0045] Fig. 20This is the chromatogram of perfluoro-1-hexanesulfonate (PFHxS).

[0046] Fig.21 This is the chromatogram of perfluoroheptanesulfonate (PFHpS).

[0047] Fig. 22 This is the chromatogram of perfluorooctanesulfonate (PFOS).

[0048] Fig.23 This is the chromatogram of 1H,1H,2H,2H-perfluorohexanesulfonate (4:2FTS).

[0049] Fig.24 This is the chromatogram of 1H,1H,2H,2H-perfluorooctanesulfonate (1H,1H,2H,2H-perfluoro-1-octanesulfonate, 6:2FTS).

[0050] Fig.25 This is the chromatogram of 1H,1H,2H,2H-perfluorodecanesulfonate (8:2FTS).

[0051] Fig.26 This is the chromatogram of 4,8-dioxanonanoate (NaDONA).

[0052] Fig. 27 This is the chromatogram of 2-[(6-chloro-1,1,2,2,3,3,4,4,5,5,6,6-dodecafluorohexyl)oxy]-1,1,2,2-tetrafluoroethanesulfonic acid (9-Chlorohexadecafluoro-3-oxanonane-1-sulfonate, 9Cl-PF3ONS). DETAILED DESCRIPTION

[0053] The present invention is further described in detail below in conjunction with the accompanying drawings and specific examples of the specification. The examples are only used to explain the present invention and are not used to limit the scope of the present invention. The test methods used in the following examples are conventional methods unless otherwise specified; the materials and reagents used are reagents and materials that can be obtained from commercial channels unless otherwise specified.

[0054] Example 1 Method for detecting 27 perfluorinated compounds in cerebrospinal fluid

[0055] 1. Specific chemical composition of 27 perfluorinated compounds:

[0056] Perfluoro-n-butanoic acid (PFBA)

[0057] Perfluoro-n-pentanoic acid (PFPeA)

[0058] Perfluoro-n-hexanoic acid (PFHxA)

[0059] Perfluoro-n-heptanoic acid (PFHpA)

[0060] Perfluoro-n-octanoic acid (PFOA)

[0061] Perfluoro-n-nonanoic acid (PFNA)

[0062] Perfluoro-n-decanoic acid (PFDA)

[0063] Perfluoro-n-undecanoic acid (PFUdA)

[0064] Perfluoro-n-dodecanoic acid (PFDoA)

[0065] Perfluoro-n-tridecanoic acid (PFTrDA)

[0066] Perfluoro-n-tetradecanoic acid (PFTeDA)

[0067] Perfluoro-1-butanesulfonamide (FBSA)

[0068] Perfluoro-1-hexanesulfonamide (FHxSA)

[0069] Perfluoro-1-octanesulfonamide (FOSA)

[0070] Perfluoro-2-methyl-3-oxahexanoic acid (2,3,3,3-Tetrafluoro-2-(1,1,2,2,3,3,3-heptafluoropropoxy)-propanoic acid, HFPO-DA)

[0071] N-methylperfluoro-1-octanesulfonamidoacetic (N-MeFOSAA)

[0072] N-Ethylperfluoro-1-octanesulfonamidoacetic (N-EtFOSAA)

[0073] Perfluoro-1-butanesulfonate (PFBS)

[0074] Perfluoro-1-pentanesulfonate (PFPeS)

[0075] Perfluoro-1-hexanesulfonate (PFHxS)

[0076] Perfluoro-1-heptanesulfonate (PFHpS)

[0077] Perfluoro-1-octanesulfonate (PFOS)

[0078] 1H,1H,2H,2H-perfluoro-1-hexanesulfonate (4:2FTS)

[0079] 1H,1H,2H,2H-perfluorooctanesulfonate (1H,1H,2H,2H-perfluoro-1-octanesulfonate, 6:2FTS)

[0080] 1H,1H,2H,2H-perfluoro-1-decanesulfonate (8:2FTS)

[0081] Dodecafluoro-3H-4,8-dioxanonanoate (NaDONA)

[0082] 2-[(6-Chloro-1,1,2,2,3,3,4,4,5,5,6,6-dodecafluorohexyl)oxy]-1,1,2,2-tetrafluoroethanesulfonic acid (9-Chlorohexadecafluoro-3-oxanonane-1-sulfonate, 9Cl-PF3ONS)

[0083] 2. Corresponding 27 isotope-labeled internal standards

[0084] 13 C 4 -PFBA, 13 C 5 -PFPeA, 13 C 5 -PFHxA, 13 C 4 -PFHpA, 13 C 8 -PFOA, 13 C 9 -PFNA, 13 C 6 -PFDA, 13 C 7 -PFUdA, 13 C 2 -PFDoA, 13 C 2 -PFTeDA, 13 C 3 -PFBS, 13 C 3 -PFHxS, 13 C 8 -PFOS, D 3 -N-MeFOSAA, D 5 -N-EtFOSAA, 13 C 2 -4:2FTS, 13 C 2 -6:2FTS and 13 C 2 -8:2FTS.

[0085] 3. Sample pretreatment

[0086] Take 250 μL of cerebrospinal fluid sample, add isotope-labeled internal standards, 1.5 ng each, to obtain the cerebrospinal fluid sample containing the internal standard, and then directly measure it on the machine.

[0087] 4. Prepare standard solution

[0088] A mixed standard stock solution containing the 27 perfluorinated compounds at a concentration of 1 μg / mL was prepared with methanol, and the concentration of the 27 perfluorinated compounds was the same, all 1 μg / mL. The mixed standard stock solution was diluted with methanol to 0.01, 0.02, 0.05, 0.1, 0.2, 0.5, 1, 2, 5, 10, 20 and 50 ng / mL.

[0089] 5. Detection

[0090] The detection conditions of high performance liquid chromatography triple quadrupole tandem mass spectrometry were:

[0091] The liquid chromatography instrument is a Shimadzu 20AD high performance liquid chromatography system, the mass spectrometer is an AB Sciex QTRAP 5500 electrospray triple quadrupole mass spectrometer, and the chromatographic column is a Waters BEH C18 high performance liquid chromatography column with a length of 100 mm, an inner diameter of 2.1 mm, and a filler particle diameter of 1.7 μm.

[0092] Data were collected in positive and negative ion modes. Tandem mass spectrometry conditions used electrospray ionization with ion source parameters of: curtain gas 40 psi, ionization voltage -4500 V, temperature 500 °C, spray gas 50 psi, auxiliary heating gas 50 psi, and collision gas medium.

[0093] A mixed solution of 2 mM ammonium acetate aqueous solution and methanol was used as the mobile phase for gradient elution, the column temperature was 40°C, the injection volume was 3 μL, and the gradient elution program was shown in Table 1:

[0094] Table 1

[0095] time Methanol to water volume ratio Flow rate (mL / min) 0~1min 20：80 0.3 1~4min Changed from 20:80 to 95:5 0.3 4~6.5min 95：5 0.3 6.5~6.6min Changed from 95:5 to 20:80 0.3 6.6~8min 20：80 0.3

[0096] The specific multiple reaction mass spectrometry parameters are shown in Table 2:

[0097] Table 2

[0098]

[0099] 6. Results Analysis

[0100] A standard curve was prepared based on the peak area and concentration of the standard solutions of the 27 perfluorinated compounds, and the contents of the 27 perfluorinated compounds in the cerebrospinal fluid sample to be tested were calculated based on the peak area of ​​the cerebrospinal fluid sample to be tested and the standard curve.

[0101] Example 2: Spiked recovery

[0102] 1. Experimental Methods

[0103] 1. According to the method of Example 1, the internal standard and 27 perfluorinated compounds were added to the cerebrospinal fluid to verify the recovery rate. In 250 μL of cerebrospinal fluid, the spiked amount of 27 perfluorinated compounds was set to 3 gradient concentrations of 1 ng / mL, 10 ng / mL and 20 ng / mL, and 17 parallel experiments were performed for each gradient concentration. The spiked amount of each perfluorinated compound in each gradient concentration was the same, and the above 3 spiked amounts were the spiked amounts of each perfluorinated compound.

[0104] Cerebrospinal fluid without the 27 perfluorinated compounds described in Example 1 was used as a blank sample.

[0105] 2. The configuration and detection method of the standard solution are the same as those in Example 1.

[0106] 3. (1) Set the mobile phase flow rate in Example 1 to 0.29 mL / min, keep other parameters unchanged, and perform spike recovery;

[0107] (2) The mobile phase flow rate in Example 1 was set to 0.31 mL / min, and other parameters were kept unchanged to perform spike recovery;

[0108] (3) The concentration of ammonium acetate in the aqueous solution of ammonium acetate in Example 1 was set to 1.9 mM, and other parameters remained unchanged, and spike recovery was performed;

[0109] (4) The concentration of ammonium acetate in the aqueous ammonium acetate solution in Example 1 was set to 2.1 mM, and other parameters remained unchanged, and spike recovery was performed;

[0110] (5) The column temperature in Example 1 was set to 39° C., and other parameters were kept unchanged, and spike recovery was performed;

[0111] (6) The column temperature in Example 1 was set to 41° C., and other parameters were kept unchanged, and spike recovery was performed.

[0112] 2. Experimental Results

[0113] According to the method of Example 1, a standard curve was prepared based on the peak area and concentration of the standard solution of 27 perfluorinated compounds, and the content of the 27 perfluorinated compounds contained in the cerebrospinal fluid sample to be tested was calculated based on the peak area and the standard curve of the cerebrospinal fluid sample to be tested. The detection limit and spike recovery results of the 27 perfluorinated compounds are shown in Table 3. The liquid chromatogram of the 27 perfluorinated compounds is shown in Table 3. Figures 1 to 27 The standard curve regression equation is as follows:

[0114] PFBA: y = 0.00058x 2 +0.22x+0.0967(r=1.0000)

[0115] PFPeA:y=0.000663x 2 +0.234x+0.0111(r=0.9992)

[0116] PFHxA:y=-1.4e-006x 2 +0.201x-0.000961(r=0.9987)

[0117] PFHpA:y=-0.000118x 2 +0.212x-0.00609(r=0.9985)

[0118] PFOA:y=-0.000206x 2 +0.18x+0.00322(r=0.9998)

[0119] PFNA:y=-7.23e-005x 2 +0.182x-0.000133(r=0.9982)

[0120] PFDA:y=6.46e-0.005x 2 +0.182x-0.0015(r=0.9991)

[0121] PFUdA:y=-1.83e-006x 2 +0.168x+0.000406(r=0.9990)

[0122] PFDoA:y=-6.38e-005x 2 +0.145x+0.000904(r=0.9980)

[0123] PFTrDA:y=-0.000382x 2 +0.177x-0.00162(r=0.9981)

[0124] PFTeDA:y=-0.000144x 2 +0.151x-0.00164(r=0.9978)

[0125] FBSA:y=-0.00128x 2 +0.432x-0.0117(r=0.9954)

[0126] FHxSA:y=-0.00186x 2 +0.437x-0.0048(r=0.9978)

[0127] FOSA:y=-0.00104x 2 +0.406x-0.00301(r=0.9990)

[0128] HFPO-DA:y=-1.65x 2 +5.17e+003x+407(r=0.9982)

[0129] N-MeFOSAA:y=0.000162x 2 +0.185x-0.00079(r=0.9990)

[0130] N-EtFOSAA:y=0.000876x 2 +0.189x-0.00231(r=0.9997)

[0131] PFBS:y=-8.8e-005x 2 +0.219x-0.000304(r=0.9964)

[0132] PFPeS:y=-0.00205x 2 +0.423x-0.00261(r=0.9992)

[0133] PFHxS:y=-0.000348x 2 +0.228x-0.001(r=0.9983)

[0134] PFHpS:y=-0.00017x 2 +0.129x-0.000571(r=0.9975)

[0135] PFOS:y=-0.000272x 2 +0.175x-0.00308(r=0.9989)

[0136] 4:2FTS:y=-0.000951x 2 +0.134x-0.000206(r=0.9986)

[0137] 6:2FTS:y=-0.000706x 2 +0.129x-9.49e-005(r=0.9986)

[0138] 8:2FTS:y=-0.000946x 2 +0.165x-0.00236(r=0.9990)

[0139] NaDONA:y=-980x 2 +2.51e+005x+602(r=0.9989)

[0140] 9Cl-PF3ONS: y = -1.66e + 003x 2 +3.38e+005x-888(r=0.9997)Table 3

[0141]

[0142]

[0143] According to the method of Example 1, the spiked recoveries at three spiked concentrations are between 77.9% and 101.3%, the relative deviation is less than 20%, and the recovery is between 75% and 120%, which meets the internationally recognized licensing standards and can achieve the simultaneous determination of 27 perfluorinated compounds with simple operation and low cost.

[0144] The flow rate is 0.29-0.31 mL / min, the concentration of ammonium acetate in the ammonium acetate aqueous solution is 1.9-2.1 mM, the column temperature is 39-40° C., the peak shape is still good, the relative deviation is less than 20%, and the recovery rate is between 75% and 120%, reaching the internationally recognized licensing standards.

[0145] Example 3 Detection of 27 perfluorinated compounds in actual cerebrospinal fluid samples

[0146] 1. Experimental Methods

[0147] 418 cerebrospinal fluid samples from different donors were collected, and the content of 27 perfluorinated compounds in the cerebrospinal fluid samples was detected using the method of Example 1.

[0148] 2. Experimental Results

[0149] As shown in Table 4, the detection rates of four perfluorinated compounds are greater than 50%, which indicates that perfluorinated compounds appear frequently in cerebrospinal fluid, indicating that the method of Example 1 of the present invention has high accuracy, good stability, and low detection rate, and is suitable for the detection of various perfluorinated compounds in cerebrospinal fluid.

[0150] Table 4

[0151]

[0152]

[0153] Comparative Example 1 Detection of 27 perfluorinated compounds in follicular fluid samples

[0154] 1. Experimental Methods

[0155] 1. According to the method of Example 1, add isotope internal standard and 27 perfluorinated compounds to the follicular fluid, directly test on the machine, and verify the recovery rate. In 250 μL follicular fluid, the spiked amount of 27 perfluorinated compounds is set to 0.25 ng (1 ng / mL) and 2.5 ng (10 ng / mL) in two gradient concentrations, and three parallel experiments are performed for each gradient concentration. The spiked amount of each perfluorinated compound in each gradient concentration is the same, and the above two spiked amounts are the spiked amounts of each perfluorinated compound.

[0156] The follicular fluid without the 27 perfluorinated compounds described in Example 1 was used as a blank sample.

[0157] 2. The configuration and detection method of the standard solution are the same as those in Example 1.

[0158] 2. Experimental Results

[0159] A standard curve was made based on the peak area and concentration of the 27 perfluorinated compound standard solutions, and the content of the 27 perfluorinated compounds in the follicular fluid sample to be tested was calculated based on the peak area and standard curve of the follicular fluid sample to be tested. The detection limits and spike recovery results of the 27 perfluorinated compounds are shown in Table 5.

[0160] Compared with cerebrospinal fluid, the matrix of follicular fluid is more complex and the matrix inhibition is stronger. The recovery rate of some compounds is only 30%, which does not meet the permitted standards. The method of Example 1 cannot achieve the determination of some perfluorinated compounds in follicular fluid.

[0161] Table 5

[0162]

[0163]

[0164] Comparative Example 2 Detection of other perfluorinated compounds in cerebrospinal fluid samples

[0165] 1. Experimental Methods

[0166] The contents of perfluorononanesulfonate (L-PFNA, PFNS), perfluorodecanesulfonate (L-PFDA, PFDS) and 2-[(8-chloro-1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8-hexafluorooctyl)oxy]-1,1,2,2-tetrafluoroethanesulfonic acid (11-Chloroeicosafluoro-3-oxaundecane-1-sulfonate, 11Cl-PF3OUdS) in cerebrospinal fluid were detected by the method of Example 1 without adding internal standard, and the spike recovery rate of 10 ng / mL spike concentration was calculated by the method of Example 2.

[0167] 2. Experimental Results

[0168] The experiment found that the recoveries of L-PFNA, L-PFDA and 11Cl-PF3OUdS in the spiked samples were low, 45.1%, 43.5% and 39.7% respectively. The detection method of Example 1 of the present invention is not suitable for detecting L-PFNA, L-PFDA and 11Cl-PF3OUdS in cerebrospinal fluid.

[0169] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the protection scope of the present invention. For ordinary technicians in this field, other different forms of changes or modifications can be made based on the above descriptions and ideas. It is not necessary and impossible to list all the implementation methods here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A method for detecting perfluorinated and polyfluorinated compounds in cerebrospinal fluid, characterized in that: After adding isotope-labeled internal standards corresponding to perfluorinated and polyfluorinated compounds to the cerebrospinal fluid sample to be tested, liquid chromatography tandem mass spectrometry detection is directly performed; The liquid chromatography conditions were as follows: mobile phase A was methanol, mobile phase B was ammonium acetate aqueous solution, gradient elution, 0-1min, the volume ratio of mobile phase A to mobile phase B was 20:80; From 1 to 4 min, the volume ratio of mobile phase A to mobile phase B changed from 20:80 to 95:5; 4-6.5 min, the volume ratio of mobile phase A to mobile phase B was 95:5; From 6.5 to 6.6 min, the volume ratio of mobile phase A to mobile phase B changed from 95:5 to 20:80; 6.6-8min, the volume ratio of mobile phase A to mobile phase B is 20:80; The chromatographic column was a Waters BEH C18 high performance liquid chromatography column with a length of 100 mm, an inner diameter of 2.1 mm, and a filler particle diameter of 1.7 μm; The mass spectrometry conditions were: curtain gas 40 psi, ionization voltage −4500 V, temperature 500 °C, spray gas 50 psi, auxiliary heating gas 50 psi, collision gas medium; The perfluoro and polyfluoro compounds are perfluorobutyric acid, perfluoropentanoic acid, perfluorohexanoic acid, perfluoroheptanoic acid, perfluorooctanoic acid, perfluorononanoic acid, perfluorodecanoic acid, perfluoroundecanoic acid, perfluorododecanoic acid, perfluorotridecanoic acid, perfluorotetradecanoic acid, perfluorobutylsulfonamide, perfluorohexylsulfonamide, perfluorooctylsulfonamide, perfluoro 2-methyl-3-oxahexanoic acid, N-methyl perfluorooctane aminoacetic acid, N-ethyl perfluorooctane aminoacetic acid, perfluorobutylsulfonic acid, perfluoropentanesulfonic acid, perfluoropentanesulfonic acid, Fluorohexylsulfonic acid, perfluoroheptylsulfonic acid, perfluorooctanesulfonic acid, 1H,1H,2H,2H-perfluorohexylsulfonic acid, 1H,1H,2H,2H-perfluorooctanesulfonic acid, 1H,1H,2H,2H-perfluorodecanesulfonic acid, ethyl 4,8-dioxo-3H-perfluorononanoate and 2-[(6-chloro-1,1,2,2,3,3,4,4,5,5,6,6-dodecafluorohexyl)oxy]-1,1,2,2-tetrafluoroethanesulfonic acid.

2. The detection method according to claim 1, characterized in that: The isotope-labeled internal standard is 13 C4-PFBA, 13 C5-PFPeA, 13 C5-PFHxA, 13 C4-PFHpA, 13 C8-PFOA, 13 C9-PFNA, 13 C6-PFDA, 13 C7-PFUdA, 13 C2-PFDoA, 13 C2-PFTeDA, 13 C3-PFBS, 13 C3-PFHxS, 13 C8-PFOS, D3-N-MeFOSAA, D5-N-EtFOSAA, 13 C2-4:2FTS, 13 C2-6:2FTS and 13 C2-8: One or more of 2FTS.

3. The detection method according to claim 1, characterized in that: The concentration of ammonium acetate is 1.9-2.1 mM.

4. The detection method according to claim 1, characterized in that: The flow rate of gradient elution was 0.29-0.31 mL / min.

5. The detection method according to claim 1, characterized in that: The detection column temperature was 39-41°C.

6. The detection method according to any one of claims 1 to 5, characterized in that: The liquid chromatograph used was a Shimadzu 20AD high performance liquid chromatography system, and the mass spectrometer was an AB Sciex QTRAP 5500 electrospray triple quadrupole mass spectrometer.

Images