Pretreatment method of serum liquid chromatography-tandem mass spectrometry

Abstract

The invention relates to a serum liquid chromatography-tandem mass spectrometry pretreatment method, which comprises: (S1) mixing a serum sample and a formic acid-containing acetonitrile solution, carrying out ultrasonic treatment, vortex oscillation and centrifugation, taking the supernatant, and diluting with a formic acid-containing aqueous solution to obtain a liquid to be purified; (S2) mixing the to-be-purified liquid with PCN-777, performing ultrasonic treatment, vortex oscillation and centrifugation, and taking supernate to obtain to-be-detected liquid; the PCN-777 is a C24H23N3O16Zr3 phospholipid removal material, and the PCN-777 is a C24H23N3O16Zr3 phospholipid removal material, and the PCN-777 is a C24H23N3O16Zr3 phospholipid removal material. According to the present invention, the serum ultra-high performance liquid chromatography-tandem mass spectrometry pretreatment method is developed by using the known MOFs material PCN-777, such that different types of phospholipids in the serum can be specifically, rapidly and effectively removed, the efficient recovery and detection of pesticide and veterinary drugs can be achieved, and the interference of phospholipids can be avoided.

Description

Technical Field

[0001] The present invention belongs to the technical field of pretreatment for liquid chromatography-mass spectrometry detection, and particularly relates to a pretreatment method for serum liquid chromatography-tandem mass spectrometry analysis. Background Art

[0002] Detecting pollutants in human blood can not only evaluate the degree of individual exposure to harmful substances, provide a scientific basis for health risks, but also detect the accumulation of pollutants at an early stage and take preventive measures to reduce the risk of disease occurrence. In addition, the detection results help to trace the source of pollutants, provide a basis for pollution control and environmental protection, and at the same time provide scientific support for formulating relevant policies and legal accountability, thus playing an important role in protecting public health and improving environmental quality. In recent years, the progress of high-resolution mass spectrometry technology has enabled researchers to simultaneously and repeatedly analyze thousands of compounds in biological samples using non-targeted methods. However, the concentrations of exogenous chemicals (such as pesticides and plasticizers) in the blood of the general population are usually hundreds to thousands of times lower than those of endogenous compounds in the sample. The ion suppression problem caused by these high-abundance endogenous chemicals often results in the failure to detect trace and ultra-trace biologically significant exogenous exposure chemicals. Therefore, how to ensure that sample analysis can unbiasedly reflect the exposure status of human chemicals is a crucial issue.

[0003] Before performing liquid chromatography-mass spectrometry detection, removing the interference of endogenous compounds in the blood sample during the sample pretreatment process is an effective solution. In non-targeted monitoring of plasma or serum samples, the most commonly used sample preparation method is to precipitate proteins using ice-cold methanol or acetonitrile. Although this method can extract the most compounds, due to the interference of endogenous compounds such as phospholipids, not only is the amount of organic solvent used large, but also the operation time is long, and the purification effect is not ideal.

[0004] Phospholipids are lipids containing phosphoric acid and are an important component of cell membranes. There are many types of phospholipids in serum, mainly including phosphatidylcholine, lysophosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidylglycerol, sphingomyelin, etc. They have a complex structure and many interferences. Phospholipids have always been the main components causing matrix effects in the liquid chromatography-mass spectrometry detection of blood samples. In particular, lecithin and lysophosphatidylcholine are the main endogenous compounds causing matrix effects, which affect the response of many compounds in the mass spectrometry, seriously affect the ionization effect of the electrospray ion source, and it is difficult to remove phospholipids by conventional methods.

[0005] CN114755355A reported a phospholipid remover and its application in removing phospholipids from biological samples. The phospholipid remover consists of component A and component B. Component A is dextran salt, and component B is a zirconium source. The molar ratio of component A to component B is 0.1 - 1.7:2.5 - 5. The dextran salt is dextran sulfate, and the zirconium source is zirconium oxychloride. The phospholipids at least include lysophosphatidylcholine. However, it is difficult for this polyanion - metal ion system to maintain good recovery of some analytes while efficiently removing phospholipids.

[0006] Shanghai Jiao Tong University reported a zirconia - coated silica core - shell type filler for selectively adsorbing phospholipids. Utilizing its large specific surface area and selective adsorption of phospholipids, a ZrO2 / SiO2 SPE column was used to pretreat serum samples. However, this article only explored the adsorption efficiency of the zirconia - coated silica core - shell type filler for phospholipids and did not explore the recovery effect of other substances.

[0007] Therefore, it is necessary to develop a new technology that can effectively remove phospholipids from serum and provide a new technical support for sample pretreatment in pollutant analysis. Summary of the Invention

[0008] To solve the deficiencies in the prior art, such as insufficient efficiency in removing phospholipids from blood samples, low recovery rate of some analytes, and complex operation, the present invention proposes a method of using MOFs to adsorb phospholipids to achieve the purpose of removing phospholipids from blood. The present invention is easy to operate, has a high phospholipid removal rate, and excellent analyte recovery rate, and can be widely applied to the residual analysis of chemical pollutants in serum. Specifically, the present invention provides the following technical solutions to solve the above problems: A pretreatment method for serum liquid chromatography - tandem mass spectrometry analysis, comprising the following steps: (S1) Mix the serum sample with an acetonitrile solution containing formic acid, ultrasonicate, vortex, and centrifuge. Take the supernatant and dilute it with an aqueous solution containing formic acid to obtain a solution to be purified. (S2) Mix the solution to be purified with PCN - 777, ultrasonicate, vortex, and centrifuge. Take the supernatant to obtain a solution to be measured. The PCN - 777 is C 24 H 23 N3O 16 Zr3, which is a complex formed by 2,4,6 - tris(4 - carboxyphenyl) - 1,3,5 - triazine and Zr in a molar ratio of 1:3.

[0009] Further, after step (S2), there is step (S3): The solution to be measured is separated and determined by UPLC - MS / MS to obtain the phospholipid removal efficiency. Further, after step (S2), there is step (S4): the test solution is separated and determined by UPLC-MS / MS, and quantified by the external standard method to obtain the content of chemical pollutants.

[0010] Further, in step (S1), the formic acid concentration in acetonitrile containing formic acid and aqueous solution containing formic acid is 0.1-0.2 wt%. The volume ratio of the serum sample to the formic acid acetonitrile solution is 1:3-5, such as 1:4.

[0011] Further, in steps (S1) and (S2), the ultrasonic frequency is 60-120 kHz; the vortex oscillation time is 30-60 s; the ultrasonic time is 5-30 min; the centrifugation speed is 8000-15000 rpm, the temperature during centrifugation is 0-10 °C, the centrifugation time is 5-20 min, and the supernatant is diluted 1:1 with an aqueous solution (0.1% formic acid).

[0012] Further, in step (S2), the dosage ratio of the solution to be purified to PCN-777 is 1 mL: 10-50 mg, preferably 1 mL: 10-30 mg.

[0013] Further, in step (S3), the selected representative phospholipid species are 2 kinds of lysophosphatidylethanolamine (LPE): LPE 16:0, LPE 18:0; 4 kinds of lysophosphatidylcholine (LPC): LPC 15:0, LPC 16:0, LPC 18:0, LPC 22:4; 4 kinds of phosphatidylcholine (PC) p- 16:0 / 18:0, PC p -16:0 / 20:1, PC p -18:0 / 14:0, PC p- 18:0 / 18:0; and 4 kinds of sphingomyelin (SM): SM d18:1 / 12:0, SM d18:1 / 14:0, SM d18:1 / 14:1, SM d18:1 / 16:0; Further, in step (S3), the chromatographic column used in the ultra-high performance liquid chromatography is ACQUITY CSH C18 (2.1 mm × 100 mm, 1.7 μm). Mobile phase: acetonitrile / water (6:4 to 4:6, v / v) (A) and isopropanol / acetonitrile (9:1 to 2:2, v / v) (B) containing 10 - 20 mM ammonium formate + 0.1 - 0.2% formic acid; gradient elution program: 40% - 43% B (0 - 2.0 min), 43% - 50% B (2.0 - 2.1 min), 50% - 54% B (2.1 - 12.0 min), 54% - 70% B (12.0 - 12.1 min), 70% - 99% B (12.1 - 18.0 min), 99% - 40% B (18.0 - 18.1 min), 40% B (18.1 - 20.0 min); flow rate is 0.35 - 0.40 mL / min; column temperature is 40 - 45 °C, injection volume is 5 - 10 μL. In the gradient elution program, the expression of the mobile phase and time is well-known in the art. For example, 40% - 43% B (0 - 2.0 min) means that within the time of 0 to 2.0 min, the mobile phase gradually changes from 40% mobile phase B (the rest is mobile phase A) to 43% mobile phase B (the rest is mobile phase A); another example, 99% - 40% B (18.0 - 18.1 min) means that within the time of 18.0 - 18.1 min, the mobile phase changes from 99% mobile phase B (the rest is mobile phase A) to 40% mobile phase B (the rest is mobile phase A), and the percentage is the volume percentage.

[0014] Further, in step (S4), for pesticides, the chromatographic column used in the ultra-high performance liquid chromatography is ACQUITY UPLC HSS T3 (2.1 mm × 100 mm, 1.8 μm); for veterinary drugs, the chromatographic column used in the ultra-high performance liquid chromatography is ACQUITY UPLC BEH C18 (2.1 mm × 100 mm, 1.7 μm).

[0015] Further, in step (S4), for pesticides, the mobile phases used in the ultra - performance liquid chromatography are: 2 - 5 mM ammonium formate + 0.01 - 0.05% (v / v) formic acid in water (A) and 2 - 5 mM ammonium formate + 0.01 - 0.05% (v / v) formic acid in methanol (B); the gradient elution program is 3% B (0 - 1.0 min), 3% - 15% B (1.0 - 1.5 min), 15% - 50% B (1.5 - 2.5 min), 50% - 70% B (2.5 - 18.0 min), 70% - 98% B (18.0 - 23.0 min), 98% B (23.0 - 27.0 min), 98% - 3% B (27.0 - 27.1 min), 3% B (27.1 - 30.0 min); the flow rate is 0.3 - 0.5 mL / min; the column temperature is 40 - 45°C, and the injection volume is 2 - 5 μL; for veterinary drugs, the mobile phases used in the ultra - performance liquid chromatography are: 0.5 - 1.0 mM ammonium fluoride + 0.1 - 0.2% (v / v) formic acid in water (A) and acetonitrile / methanol (v / v = 1 / 1 to 1 / 1.5) (B); the flow rate is 0.3 - 0.5 mL / min. The gradient elution program is 3 - 10% B (0 - 2.0 min), 10% - 15% B (2.0 - 5.0 min), 10 - 15% B (5.0 - 10.0 min), 15% - 30% B (10.0 - 15.0 min), 30% - 50% B (15.0 - 20.0 min), 50% - 100% B (20.0 - 24.0 min), 100% B (24.0 - 28.0 min), 100% - 3% B (28.0 - 28.5 min), 3 - 5% B (28.5 - 29.0 min); the flow rate is 0.3 - 0.5 mL / min; the column temperature is 40 - 45°C, and the injection volume is 3 - 5 μL.

[0016] The present invention also provides the use of the metal - organic framework PCN - 777 in removing phospholipids from blood samples, and the PCN - 777 is C 24 H 23 N3O 16 Zr3: The structural formula is as follows: 。

[0017] PCN-777 is a known MOF material. For details, please refer to the literature "A Highly Stable Zeotype Mesoporous Zirconium Metal–Organic Framework with Ultralarge Pores, Angew Chem Int Ed Engl. 2015 Jan 2;54(1):149-54. doi:10.1002 / anie.201409334.". In the present invention, for the first time, this MOF is used as a phospholipid adsorbent in serum samples, and it is found that it can specifically adsorb and remove phospholipids without interfering with other components to be detected. Such a characteristic of specifically and efficiently adsorbing phospholipids has not been observed in other MOFs.

[0018] Further, the metal-organic framework PCN-777 is obtained by a preparation method including the following steps: a zirconium source and the ligand 2,4,6-tris(4-carboxyphenyl)-1,3,5-triazine (TATB) are dissolved in an organic solvent in the presence of a catalyst, the mixture is heated, cooled, washed, the white powder precipitate is collected, and dried. The catalyst is selected from at least one of trifluoroacetic acid, acetic acid, and formic acid.

[0019] Furthermore, the zirconium source is selected from ZrOCl2, ZrCl4, and their hydrates; the organic solvent is selected from at least one of N,N-diethylformamide, N,N-dimethylformamide, and tetrahydrofuran. The heating temperature is 100-140 °C, and the heating time is 5-15 h.

[0020] Furthermore, the dosage ratio of the zirconium source, 2,4,6-tris(4-carboxyphenyl)-1,3,5-triazine, the catalyst, and the solvent is 200-360 mg: 60-90 mg: 0.4-0.6 mL: 10-20 mL.

[0021] The inventors unexpectedly found that among numerous metal-organic frameworks, PCN-777 exhibits an excellent effect of adsorbing and removing phospholipids in serum. The possible reason is that PCN-777 has a large specific surface area and a pore size matching that of phospholipids. In addition, Zr in PCN-777 4+ and the phosphate group in phospholipids can bind through electrostatic interaction. Description of the Drawings

[0022] Figure 1 is the SEM image of the PCN-777 obtained in the preparation example; Figure 2 is the N2 adsorption-desorption curve and pore size distribution diagram of the PCN-777 obtained in the preparation example; Figure 3are the liquid chromatograms of PCN-777 before and after adsorption of phospholipid SM d18:1 / 16:0; Figure 4 is the adsorption performance of PCN-777 for 14 kinds of phospholipids. Specific Embodiments

[0023] In the following examples, the experimental methods are conventional methods unless otherwise specified; the reagents and materials can be obtained from commercial sources unless otherwise specified.

[0024] Preparation Example Put 360 mg of ZrOCl2·8H2O, 90 mg of 2,4,6-tris(4-carboxyphenyl)-1,3,5-triazine (TATB) and 0.6 mL of trifluoroacetic acid into a Pyrex glass bottle, and add 12 mL of N,N-diethylformamide (DEF) to dissolve by ultrasonic. Heat the mixture to 120 °C and react for 12 h. After cooling to room temperature, wash 5 times with N,N-dimethylformamide (DMF) and acetone, centrifuge and wash, collect the white powder product, which is PCN-777, and dry it under vacuum for standby.

[0025] Figure 1 is the SEM image of PCN-777 obtained in the preparation example. It can be seen that the prepared PCN-777 presents an octahedral structure.

[0026] Figure 2 is the N2 adsorption-desorption curve and pore size distribution diagram of PCN-777 obtained in the preparation example. The nitrogen adsorption experiment was carried out at 77 K, Figure 2 The results show that the nitrogen adsorption capacity of PCN-777 at 1 bar is about 103 cm 3 ·g -1 , and the Brunauer–Emmett–Teller specific surface area is 300.14 m 2 ·g -1 , with a mesoporous cage of 3.5 nm.

[0027] Example 1 The representative phospholipids selected were: 2 kinds of lysophosphatidylethanolamine (LPE): LPE 16:0, LPE 18:0; 4 kinds of lysophosphatidylcholine (LPC): LPC 15:0, LPC 16:0, LPC 18:0, LPC 22:4; 4 kinds of phosphatidylcholine (PC): PC p-16:0 / 18:0, PC p-16:0 / 20:1, PC p-18:0 / 14:0, PC p-18:0 / 18:0; and 4 kinds of sphingomyelin (SM): SMd18:1 / 12:0, SM d18:1 / 14:0, SMd18:1 / 14:1, SM d18:1 / 16:0, which were the target representative phospholipids.

[0028] Chromatographic separation of phospholipid analytes was carried out using an ACQUITY CSH C18 (2.1 mm × 100 mm, 1.7 μm) column. Mobile phase: acetonitrile / water (6:4, v / v) with 10 mM ammonium formate + 0.1% formic acid (A) and isopropanol / acetonitrile (9:1, v / v) with 10 mM ammonium formate + 0.1% formic acid (B); the gradient elution program was 40% - 43% B (0 - 2.0 min), 43% - 50% B (2.0 - 2.1 min), 50% - 54% B (2.1 - 12.0 min), 54% - 70% B (12.0 - 12.1 min), 70% - 99% B (12.1 - 18.0 min), 99% - 40% B (18.0 - 18.1 min), 40% B (18.1 - 20.0 min); the flow rate was 0.35 mL / min; the column temperature was 45 °C, the injection volume was 5 μL, and the total cycle time for each sample was 30 min.

[0029] Mass spectrometry analysis was performed using a Waters Xevo TQ-S triple quadrupole mass spectrometer and operated in the multiple reaction monitoring (MRM) mode. The main parameters were as follows: ion source: electrospray ionization source (ESI); ionization mode: positive ion mode; ion source temperature: 350 °C; parameters such as retention time (RT), quantitative ion pairs, qualification ion pairs, collision energy, and declustering potential are shown in Table 1.

[0030] Table 1 Mass spectrometry parameters of 14 phospholipids 。

[0031] Take 500 μL of serum, add 5 mg of PCN-777 powder, vortex for 5 min, then centrifuge at 10000 rpm for 5 min. Take 100 μL of the supernatant and mix it with 400 μL of acetonitrile solution containing 0.1% formic acid, sonicate for 15 min, centrifuge at 12000 rpm at 4°C for 10 min. Take 250 μL of the supernatant, dilute it with an equal volume of water containing 0.1% formic acid, and take 200 μL for on-machine detection. The result shows that there is no phospholipid removal effect, indicating that adding the material before protein precipitation with acetonitrile cannot remove phospholipids.

[0032] Take 100 μL of the supernatant and mix it with 400 μL of acetonitrile solution containing 0.1% formic acid, sonicate for 15 min, then centrifuge at 12000 rpm at 4°C for 10 min. Take 250 μL of the supernatant, dilute it with an equal volume of water containing 0.1 wt% formic acid. Add 5 mg of PCN-777 powder to 500 μL of the diluted solution, vortex for 5 min, centrifuge at 10000 rpm for 5 min, and take 200 μL of the supernatant for on-machine detection. Figure 3 It is the adsorption performance of PCN-777 for 14 kinds of phospholipids. After protein precipitation with acetonitrile, PCN-777 shows excellent adsorption performance for 14 kinds of phospholipids. It shows that before adsorbing phospholipids with PCN-777, it is necessary to precipitate proteins with acetonitrile. The adsorption rate calculation formula is as follows: ; The peak area is the peak area of the characteristic peak in the liquid chromatogram. The retention time corresponding to each phospholipid is different, as shown in Table 1 specifically. The results show that after protein precipitation, the adsorption rates of PCN-777 for phospholipids are as follows: the adsorption rates for 2 kinds of LPE are above 95%, the adsorption rates for 4 kinds of LPC are 80%-95%, the adsorption rates for 3 kinds of PC are above 95%, and the adsorption rates for 4 kinds of SM are 80%-99%. The above results indicate that PCN-777 has excellent phospholipid adsorption performance for serum after protein precipitation with acetonitrile.

[0033] Figure 3 It is the liquid chromatogram of PCN-777 before and after adsorbing phospholipid SM d18:1 / 16:0. Figure 4 It is the adsorption performance of PCN-777 for 14 kinds of phospholipids. The inventors also tried other kinds of MOFs, such as ZIF-8 and UIO-66, and found that their adsorption performance for 14 kinds of phospholipids is far inferior to that of PCN-777, and the phospholipid adsorption rate is only 40-60%.

[0034] Example 2 In the spike recovery experiment, 1 mL of serum was taken into a 15 mL polypropylene centrifuge tube, and then 4 mL of acetonitrile solution containing 0.1% formic acid was added and vortexed for 30 s, followed by sonication for 15 min. After centrifugation at 12000 rpm for 10 min at 4°C, 4 mL of the supernatant was taken, diluted with an equal volume of water containing 0.1% formic acid, and spiked with chemical hazards at a concentration level of 50 µg kg- 1 5 mg of PCN-777 was dispersed in 500 µL of the supernatant, vortexed for 5 min, and centrifuged at 10000 r / min for 5 min to separate PCN-777. 200 µL of the supernatant was taken and the concentration of chemical hazard factors was analyzed using HPLC-MS / MS.

[0035] For pesticide standards, liquid chromatography analysis was performed using a Waters Acquity Ultra Performance LC high performance liquid chromatograph. Chromatographic separation of the analytes was carried out using an ACQUITY UPLC HSS T3 (2.1 mm × 100 mm, 1.8 μm) column. The column temperature was 40°C and the injection volume was 2 μL. Mobile phase: 2 mM ammonium formate + 0.01% (v / v) formic acid in water (A) and 2 mM ammonium formate + 0.01 w% formic acid in methanol (B); flow rate: 0.3 mL / min. The gradient elution program was 3% B (0 - 1.0 min), 3% - 15% B (1.0 - 1.5 min), 15% - 50% B (1.5 - 2.5 min), 50% - 70% B (2.5 - 18.0 min), 70% - 98% B (18.0 - 23.0 min), 98% B (23.0 - 27.0 min), 98% - 3% B (27.0 - 27.1 min), 3% B (27.1 - 30.0 min). The total cycle time for each sample was 30.0 min.

[0036] Mass spectrometry analysis was performed using a Waters Xevo TQ-S triple quadrupole mass spectrometer and operated in the multiple reaction monitoring (MRM) mode. The main parameters were as follows: ion source: electrospray ionization source (ESI); ionization mode: positive ion mode; ion source temperature: 350°C.

[0037] For veterinary drug reference standards, liquid chromatography analysis was performed using a Waters Acquity Ultra Performance LC high-performance liquid chromatograph. Chromatographic separation of the analyte was carried out using an ACQUITY UPLC BEH C18 column (2.1 mm × 100 mm, 1.7 μm). The column temperature was 40 °C and the injection volume was 3 μL. Mobile phase: 0.5 mM ammonium fluoride + 0.1 wt% formic acid aqueous solution (A) and acetonitrile / methanol (v / v = 1 / 1) (B); flow rate: 0.3 mL / min. The gradient elution program was 3% B (0 - 2.0 min), 3% - 15% B (2.0 - 5.0 min), 15% B (5.0 - 10.0 min), 15% - 30% B (10.0 - 15.0 min), 30% - 50% B (15.0 - 20.0 min), 50% - 100% B (20.0 - 24.0 min), 100% B (24.0 - 28.0 min), 100% - 3% B (28.0 - 28.5 min), 3% B (28.5 - 29.0 min). The total cycle time for each sample was 29.0 min.

[0038] Mass spectrometry analysis was performed using a Waters Xevo TQ-XS triple quadrupole mass spectrometer and operated in the multiple reaction monitoring (MRM) mode. The main parameters were as follows: ion source: electrospray ionization source (ESI); ionization mode: positive ion mode; ion source temperature: 400 °C.

[0039] 553 pesticides and veterinary drugs were tested, and the results are shown in Table 2 below.

[0040] To evaluate the total recycling performance of the material, the accuracy and precision of the method were evaluated through a recovery experiment at an addition level of 50 ppb (n = 3). Among them, the recovery rate and relative standard deviation (RSD) represent the accuracy and precision of the method respectively. As can be seen from Table 2 and Table 3, for serum samples, PCN-777 achieved good recovery rates R (35% - 130%) for 553 chemical hazards (agricultural and veterinary drugs) at a concentration level of 50 ppb, and the RSD was 0.01% - 20%. Although the recovery rates of some agricultural and veterinary drugs were relatively low, all compounds could be detected, meeting the qualitative requirements for non-directed screening. In addition, among the 553 chemical hazards, the matrix effect factors (MF) of 507 (88.4%) chemical hazards in human serum were between 0.7 and 1.3, showing a slight inhibitory or enhancing effect on the matrix. If PCN-777 was not used to treat the serum, a more serious matrix effect would occur, resulting in the inability to detect trace chemical hazards. For example, for acephate, after treatment with PCN-777, the matrix effect ME was 1.12; if PCN-777 was not used for treatment, ME reached 2.36; if UIO-66 was used for treatment, ME was 1.74.

[0041] Table 2 Information on 337 pesticides and spike recovery rates (50 µg kg -1 ) 。

[0042] Table 3 Information on 216 veterinary drugs and spike recovery rates (50 µg kg -1 ) 。

Claims

1. A pretreatment method for serum liquid chromatography-tandem mass spectrometry analysis, characterized in that, It includes the following steps: (S1) Mix the serum sample and the acetonitrile solution containing formic acid, perform ultrasonic treatment, vortex oscillation, and centrifugation, take the supernatant and dilute it with an aqueous solution containing formic acid to obtain the solution to be purified; (S2) The liquid to be purified is mixed with PCN-777, ultrasonically treated, vortex-shaken, and centrifuged, and the supernatant is taken to obtain the test solution; the PCN-777 is C 24 H 23 N3O 16 Zr3, which is a complex formed by 2,4,6-tris(4-carboxyphenyl)-1,3,5-triazine and Zr in a molar ratio of 1:

3.

2. The preprocessing method according to claim 1, characterized in that After step (S2), there is also step (S3): The solution to be measured is separated and determined by UPLC-MS / MS to obtain the removal efficiency of phospholipids.

3. The pre-treatment method according to claim 1, characterized in that, After step (S2), there is also step (S4): The solution to be measured is separated and determined by UPLC-MS / MS, and quantitative analysis is carried out by the external standard method to obtain the content of chemical contaminants.

4. The pre-treatment method according to claim 1, characterized in that, In step (S1), the concentration of formic acid in the acetonitrile containing formic acid and the aqueous solution containing formic acid is 0.1-0.2 wt%, and the volume ratio of the serum sample to the formic acid acetonitrile solution is 1:3-5.

5. The preprocessing method according to claim 1, wherein In steps (S1) and (S2), the ultrasonic frequency is 60-120 kHz; the vortex oscillation time is 30-60 s; the ultrasonic time is 5-30 min; the centrifugation speed is 8000-15000 rpm, the temperature during centrifugation is 0-10 °C, the centrifugation time is 5-20 min, and the supernatant is diluted with an aqueous solution containing 0.1-0.2 wt% formic acid.

6. The preprocessing method according to claim 1, wherein In step (S2), the dosage ratio of the solution to be purified to PCN-777 is 1 mL: 10-50 mg.

7. The pre-treatment method according to claim 1, characterized in that In step (S2), the dosage ratio of the solution to be purified to PCN-777 is 1 mL: 10-30 mg.

8. The preprocessing method according to claim 2, wherein In step (S3), the chromatographic column used in ultra-high performance liquid chromatography is ACQUITY CSH C18; mobile phase A: acetonitrile / water containing 10-20 mM ammonium formate + 0.1-0.2 wt% formic acid, the volume ratio of acetonitrile to water is 6:4 to 4:6, mobile phase B: isopropanol / acetonitrile containing 10-20 mM ammonium formate + 0.1-0.2 wt% formic acid, the volume ratio of propanol to acetonitrile is 9:1 to 2:2; the gradient elution program is 40%-43% B, 0-2.0 min; 43%-50% B, 2.0-2.1 min; 50%-54% B, 2.1-12.0 min; 54%-70% B, 12.0-12.1 min; 70%-99% B, 12.1-18.0 min; 99%-40% B, 18.0-18.1 min; 40% B, 18.1-20.0 min; the flow rate is 0.35-0.40 mL / min; the column temperature is 40-45 °C, and the injection volume is 5-10 μL.

9. The pre-treatment method according to claim 3, characterized in that In step (S4), for pesticides, the chromatographic column used in the ultra-high performance liquid chromatography is ACQUITY UPLC HSS T3; for veterinary drugs, the chromatographic column used in the ultra-high performance liquid chromatography is ACQUITY UPLC BEH C18; For pesticides, the mobile phase used in the ultra-high performance liquid chromatography method is: 2 - 5 mM ammonium formate + 0.01 - 0.05 wt% formic acid in water (A) and 2 - 5 mM ammonium formate + 0.01 - 0.05 wt% formic acid in methanol (B); the gradient elution program is 3% B, 0 - 1.0 min; 3% - 15% B, 1.0 - 1.5 min; 15% - 50% B, 1.5 - 2.5 min; 50% - 70% B, 2.5 - 18.0 min; 70% - 98% B, 18.0 - 23.0 min; 98% B, 23.0 - 27.0 min; 98% - 3% B, 27.0 - 27.1 min; 3% B, 27.1 - 30.0 min; the flow rate is 0.3 - 0.5 mL / min; the column temperature is 40 - 45 °C, and the injection volume is 2 - 5 μL; for veterinary drugs, the mobile phase used in the ultra-high performance liquid chromatography method is: 0.5 - 1.0 mM ammonium fluoride + 0.1 - 0.2 wt% formic acid in aqueous solution (A) and acetonitrile / methanol with a volume ratio of 1:1 - 1.5 (B); the flow rate: 0.3 - 0.5 mL / min; the gradient elution program is 3 - 10% B, 0 - 2.0 min; 10% - 15% B, 2.0 - 5.0 min; 10 - 15% B, 5.0 - 10.0 min; 15% - 30% B, 10.0 - 15.0 min; 30% - 50% B, 15.0 - 20.0 min; 50% - 100% B, 20.0 - 24.0 min; 100% B, 24.0 - 28.0 min; 100% - 3% B, 28.0 - 28.5 min; 3 - 5% B, 28.5 - 29.0 min; the flow rate is 0.3 - 0.5 mL / min; the column temperature is 40 - 45 °C, and the injection volume is 3 - 5 μL.

10. Use of metal-organic framework PCN-777 in removing phospholipids from blood samples, wherein the PCN-777 is C 24 H 23 N3O 16 Zr3; the metal-organic framework PCN-777 is obtained by a preparation method comprising the following steps: a zirconium source and a ligand 2,4,6-tris(4-carboxyphenyl)-1,3,5-triazine (TATB) are dissolved in an organic solvent in the presence of a catalyst, the mixture is heated, cooled, washed, the white powder precipitate is collected, and dried; the catalyst is selected from at least one of trifluoroacetic acid, acetic acid, and formic acid.

Images