An analytical method for the migration of phthalates in samples enriched with magnetic MOF materials

Abstract

The present invention discloses an analytical method for the amount of phthalate ester migration in a sample enriched with a magnetic MOF material. The method belongs to the field of detection technology and comprises the following steps: pre-treating the sample to be tested so that potential phthalates in the sample migrate into a pre-treatment solution; mixing the magnetic MOF material with the pre-treatment solution and adsorbing the phthalates therein; eluting the phthalates from the magnetic MOF material with an eluent; collecting the eluate, dehydrating it through a filter membrane, and then performing gas chromatography-mass spectrometry detection. The method utilizes magnetic dispersion solid-phase extraction technology to enrich the phthalates that migrate in the sample. The method is simple to operate, does not require column loading, uses a small amount of organic solvent, has high enrichment efficiency, minimizes target compound loss, and is highly accurate. It can measure at least 26 phthalates with a low limit of quantification, making it highly suitable for determining the amount of phthalate ester migration in human body contact materials or food contact materials, particularly toys.

Description

Technical Field

[0001] The present invention belongs to the field of detection technology, and in particular relates to an analysis method for the migration amount of phthalates in a sample enriched with a magnetic MOF material. Background Art

[0002] Phthalates (PAEs) are a class of environmental endocrine disruptors, collectively known as esters of phthalic acid. Phthalates can negatively impact human health, causing precocious puberty in children, damaging the male reproductive system, and possessing teratogenic and carcinogenic properties. PAEs are plastic and flexible, and are widely used as additives in plastic products such as toys. PAEs are oil-soluble and generally lack strong chemical bonds to plastics, making them susceptible to migration over time or due to environmental changes. Over time, these substances can enter the human body through migration, posing a health risk.

[0003] In the existing technology, standards have been established for the detection technology of PAEs in toys. For example, GB / T22048-2015 "Determination of Certain Phthalate Ester Plasticizers in Toys and Children's Products" stipulates the determination method of dibutyl phthalate, butyl benzyl phthalate, di(2-ethylhexyl) phthalate, di-n-octyl phthalate, diisononyl phthalate and diisodecyl phthalate in toys and children's products. However, the value measured by this standard is the content of PAEs in toys, which cannot be used to assess the amount of PAEs that enter the human body through the medium during use. The part of PAEs that is directly harmful to the human body is the part that dissolves in sweat and saliva.

[0004] Studying the migration of PAEs in artificial sweat and saliva using simulated exposure principles has been a hot topic in recent years. Due to the low levels of PAEs released from artificial sweat and saliva, and the high salt content of these substances, the immersion solutions obtained from these simulated migration processes cannot be directly analyzed by gas chromatography-mass spectrometry, requiring pretreatment such as extraction and enrichment. Currently, commonly used extraction methods include liquid-liquid extraction, solid-phase extraction, and headspace solid-phase microextraction (SPME). These methods consume significant amounts of organic reagents, resulting in losses of target compounds during extraction and concentration. In particular, SPE can easily lead to clogging of SPE cartridges, while headspace solid-phase microextraction is only suitable for a few PAEs.

[0005] Chinese patent document CN108709947A discloses a method for determining the migration amount of phthalate plasticizers in food contact materials. This invention uses supramolecular solvent dispersive liquid-liquid microextraction technology to enrich phthalate plasticizers in the migration solution of food contact materials, and optimizes the main factors affecting the extraction effect: the type and amount of alkyl alcohol, the amount of tetrahydrofuran, the vortex time, and other conditions. Furthermore, ultra-high performance liquid chromatography-tandem mass spectrometry combined with isotope dilution and other techniques is used to establish an analytical method for determining the migration amount of phthalate plasticizers in food contact materials using supramolecular solvent dispersive liquid-liquid microextraction-ultra-high performance liquid chromatography-tandem mass spectrometry. However, this method is relatively cumbersome, requires a large amount of organic solvent, and may potentially contaminate the sample.

[0006] Magnetic dispersion solid-phase extraction (SPE) uses magnetic materials as adsorbents, which are evenly dispersed in a sample solution. Separation of the adsorbent and sample solution occurs under the influence of an external magnetic field. This technique offers advantages such as simplicity and speed, overcoming the shortcomings of traditional SPE. Metal-organic frameworks (MOFs) are a class of microporous crystalline materials composed of organic ligands and metals assembled through coordination bonds. MOF can be compounded with magnetic materials (such as Fe3O4) through direct magnetization and other methods to obtain functionalized MOF. Magnetic MOF has the characteristics of high specific surface area, large porosity, and good thermal stability. It can be effectively separated under the action of an external magnetic field, and has selective adsorption separation ability and good enrichment ability. Combining the excellent performance of MOF materials with the magnetic separation characteristics of magnetic materials such as Fe3O4, magnetic MOF materials have been successfully used as high-performance separation adsorbents for magnetic dispersed solid-phase extraction. Currently, they are widely used in the enrichment and analysis of food, environmental and biological samples, such as the separation and enrichment of chondroitin from shellfish and seafood, the enrichment of heavy metals such as cadmium, lead, zinc and chromium in agricultural products, and the enrichment of Sudan dyes and pesticide residues in tomato sauce, juice and rice.

[0007] Du Yingying et al. used liquid-liquid extraction to study the migration behavior of six phthalate plasticizers (DBP, BBP, DEHP, DNOP, DINP and DIDP) in plasticizer materials for children's products in four different simulants (simulated saliva, acidic simulated sweat, alkaline simulated sweat and oily food simulants) (Du Yingying, Liu Wendong, Hao Xiaohong, et al. Migration behavior of six plasticizers in plasticized materials for children's products in four different simulants [J]. Plastics Science and Technology, 2019, 47(5): 85-88.). Niu Zengyuan et al. used C 18The migration of DBP, DEP, and DNOP in textiles in artificial sweat was studied using reversed-phase solid-phase extraction (Niu Zengyuan, Fang Liping, Yang Guipeng, et al. Migration of phthalate environmental hormones in textiles in artificial sweat [J]. Journal of Textile Research, 2006, 27(2):74-77.). Yang Zuojun et al. used headspace solid-phase microextraction to study the migration of DEHP, DBP, BBP, DCHP, and DNOP in PVC plastics in artificial sweat and artificial saliva (Yang Zuojun, Wang Chengyun, Zhang Weiya, et al. Study on the migration behavior of phthalate plasticizers in PVC plastics in body fluids [J]. Polyvinyl Chloride, 2006(3):25-32.). The above methods can only determine a few phthalates, and the pretreatment process is complex and time-consuming, resulting in a large loss of target compounds. So far, there has been no report on the migration of phthalates in artificial sweat and artificial saliva in samples enriched with magnetic MOF materials. Summary of the Invention

[0008] The present invention provides an analytical method for the amount of phthalate migration in a sample enriched with a magnetic MOF material. The method utilizes magnetic dispersed solid-phase extraction technology to enrich the phthalate migrating in the sample. The method is simple to operate, does not require column loading, uses a small amount of organic solvent, has high enrichment efficiency, minimizes target compound loss, and has high accuracy. The method can determine at least 26 phthalates with good sensitivity, and is very suitable for determining the amount of phthalate migration in human body contact materials or food contact materials, especially toys.

[0009] The specific technical solutions adopted are as follows:

[0010] A method for analyzing the migration amount of phthalates in a sample enriched with a magnetic MOF material comprises the following steps:

[0011] (1) pre-treating the sample to be tested so that potential phthalates in the sample to be tested migrate into the pre-treatment solution;

[0012] (2) mixing the magnetic MOF material with the pretreatment liquid and adsorbing the phthalates therein, then eluting the phthalates from the magnetic MOF material with an eluent, collecting the eluate, dehydrating it through a filter membrane, and then performing gas chromatography-mass spectrometry detection;

[0013] The magnetic MOF material is Fe3O4@SiO2@UiO-67, and Fe3O4@SiO2@UiO-67 is a composite adsorbent of Fe3O4 with SiO2 coated on the surface and loaded with a metal organic framework UiO-67.

[0014] In the Fe3O4@SiO2@UiO-67, the mass ratio of the surface SiO2-coated Fe3O4 to the metal organic framework UiO-67 is 1:5-10. The above mass ratio range is conducive to the adsorption of phthalate compounds by the magnetic MOF material.

[0015] The Fe3O4@SiO2@UiO-67 is obtained by compounding UiO-67 and Fe3O4@SiO2 (Fe3O4 coated with SiO2 on the surface); UiO-67 and Fe3O4@SiO2 can be purchased directly or synthesized according to the records of the prior art. The specific optional preparation method of Fe3O4@SiO2@UiO-67 is: dispersing Fe3O4@SiO2 in N,N'-dimethylformamide solution, adding zirconium chloride, 4,4'-biphenyldicarboxylic acid and acetic acid solution respectively, reacting in a reactor, and separating Fe3O4@SiO2@UiO-67 by magnetic separation at room temperature.

[0016] The functional groups in UiO-67 have good selectivity, affinity and stability. Phthalate compounds have a good adsorption effect on the surface of UiO-67, and through magnetic effect, the Fe3O4@SiO2@UiO-67 after enrichment of the compounds is easy to separate from the solution.

[0017] The samples to be tested include human body contact materials, food contact materials, etc. Preferably, the samples to be tested are toys.

[0018] The phthalates include dimethyl phthalate (DMP), diethyl phthalate (DEP), diisopropyl phthalate (DIPrP), diallyl phthalate (DAP), dipropyl phthalate (DPrP), diisobutyl phthalate (DIBP), dibutyl phthalate (DBP), di(2-methoxy)ethyl phthalate (DMEP), di(4-methyl-2-pentyl) phthalate (BMPP), di(2-ethoxy)ethyl phthalate (DEEP), dipentyl phthalate (DPP), dihexyl phthalate (DHXP), butyl phthalate (DBP), diisobutyl phthalate (DIBP), di ... Benzyl ester (BBP), di(2-butoxy)ethyl phthalate (DBEP), dicyclohexyl phthalate (DCHP), diheptyl phthalate (DHP), di(2-ethyl)hexyl phthalate (DEHP), diphenyl phthalate (DPhP), di-n-octyl phthalate (DNOP), dibenzyl phthalate (DBzP), dinonyl phthalate (DNP), didecyl phthalate (DnDP), n-pentyl isopentyl phthalate (DnIPP), diisopentyl phthalate (DIPP), dioctyl terephthalate (DOTP), dioctyl isophthalate (DOIP).

[0019] Preferably, the sample to be tested is a toy; in step (1), the method for preparing the pretreatment liquid is: soaking the toy sample in an artificial simulated liquid at room temperature for ≥2 hours, vortexing the soaking process, and the obtained soaking liquid is the pretreatment liquid; the artificial simulated liquid is artificial simulated sweat or artificial simulated saliva.

[0020] Preferably, in step (2), the ratio of the amount of magnetic MOF material to the pretreatment liquid is 50-150 mg:50 mL.

[0021] Preferably, in step (2), the adsorption time is 15-45 min; after the adsorption is completed, the magnetic MOF material adsorbed with phthalate can be separated by an external magnetic field.

[0022] The eluent is acetonitrile, acetone or methanol, and 50-150 mg of the magnetic MOF material corresponds to 1-5 mL of the eluent. After the elution is completed, the magnetic MOF material can be separated from the eluent by the action of an external magnetic field.

[0023] Further preferably, the eluent is acetonitrile. Experimental comparison shows that acetonitrile is the optimal eluent with the best elution effect.

[0024] Preferably, the eluate is dehydrated using anhydrous sodium sulfate.

[0025] Preferably, the gas chromatography-mass spectrometry detection conditions are as follows: the carrier gas is helium at a flow rate of 1.0 mL / min; the chromatographic column is an HP-5 quartz capillary column; the injection volume is 1.0 μL; the programmed temperature is: 60°C for 1 min, then increased to 220°C at 20°C / min, maintained for 4 min, then increased to 250°C at 5°C / min, maintained for 1 min, then increased to 290°C at 20°C / min, maintained for 5 min; non-split injection; the transmission line temperature is 280°C; the mass spectrometry ionization mode is an electron bombardment ion source, the scanning mode is a selected ion monitoring mode, the ionization energy is 70 eV; and the ion source temperature is 250°C-280°C.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] (1) The method of the present invention utilizes magnetic dispersion solid phase extraction technology to enrich the phthalates migrated from the sample and further utilizes gas chromatography-mass spectrometry to analyze and determine. Compared with the traditional extraction method, the method of the present invention is simple to operate. By utilizing the effect of an external magnetic field, the magnetic MOF material can be quickly separated from the soaking solution and the eluent. The adsorption and enrichment efficiency is high, the amount of organic solvent used is small, and the loss of the target compound is small. Furthermore, since the phthalates in the pretreatment solution are enriched, the concentration is greatly improved, making the peak area of ​​the quantitative ion more accurate, the method of the present invention has high accuracy.

[0028] (2) The method of the present invention has good applicability and can be used to determine at least 26 phthalates. It has good sensitivity and a low limit of quantification and is very suitable for determining the migration of phthalates in materials that come into contact with the human body or food, especially in toys. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is the total ion current chromatogram of various phthalates;

[0030] Among them, 1 is dimethyl phthalate, 2 is diethyl phthalate, 3 is diisopropyl phthalate, 4 is diallyl phthalate, 5 is dipropyl phthalate, 6 is diisobutyl phthalate, 7 is dibutyl phthalate, 8 is di(2-methoxy)ethyl phthalate, 9 is di(4-methyl-2-pentyl) phthalate, 10 is di(2-ethoxy)ethyl phthalate, 11 is dipentyl phthalate, 12 is dihexyl phthalate, 13 is butylbenzyl phthalate ester, 14 is di(2-butoxy)ethyl phthalate, 15 is dicyclohexyl phthalate, 16 is diheptyl phthalate, 17 is di(2-ethyl)hexyl phthalate, 18 is diphenyl phthalate, 19 is di-n-octyl phthalate, 20 is dibenzyl phthalate, 21 is dinonyl phthalate, 22 is didecyl phthalate, 23 is n-pentyl isopentyl phthalate, 24 is diisopentyl phthalate, 25 is dioctyl terephthalate, and 26 is dioctyl isophthalate. DETAILED DESCRIPTION

[0031] The present invention will be further described below in conjunction with the examples and accompanying drawings. It should be understood that these examples are intended to illustrate the present invention only and are not intended to limit the scope of the invention. The operating methods in the following examples where no specific conditions are specified are generally performed under conventional conditions or as recommended by the manufacturer.

[0032] The Fe3O4@SiO2@UiO-67 used in the examples was prepared according to the description in the reference (Yang Qingfeng. Synthesis of Zr-MOF composite adsorbent and its application in removing glyphosate residues [D]. Northwest Agriculture and Forestry University.):

[0033] The specific steps are as follows: adding Fe3O4 to an ethanol solution, then adding ammonia water, and dropping tetraethyl orthosilicate and stirring to fully react, washing the reactant with anhydrous ethanol and water and then vacuum drying to obtain Fe3O4@SiO2; dispersing the obtained Fe3O4@SiO2 in an N,N'-dimethylformamide solution, adding zirconium chloride, 4,4'-biphenyldicarboxylic acid and acetic acid solution respectively, heating at 120°C in a reactor for 24 hours, and magnetically separating Fe3O4@SiO2@UiO-67 after reaching room temperature. In Fe3O4@SiO2@UiO-67, the mass ratio of Fe3O4@SiO2 to UiO-67 is 1:7.

[0034] Example 1

[0035] (1) Standard substances

[0036] The standard substances used in this example are shown in Table 1;

[0037] Table 1 Chemical information of standard substances

[0038]

[0039]

[0040] (2) Preparation of standard working solution:

[0041] Accurately weigh 10 mg of each of the 26 reference standards, dissolve in n-hexane, and dilute to volume in a 10 mL volumetric flask to prepare a 1 mg / mL standard stock solution. Accurately pipette an appropriate amount of each standard stock solution and dilute with blank matrix solution to prepare a series of mixed standard working solutions with concentrations of 50, 100, 200, 500, 1000, 1500, and 2000 μg / L.

[0042] (3) Preparation of artificial simulated fluid:

[0043] 5.00 g of sodium chloride, 1.00 g of urea, and 1.00 g of 90% lactic acid were weighed separately in 900 mL of pure water, the pH was adjusted to 6.5 with 1% sodium hydroxide solution, and then the volume was adjusted to 1 L to prepare artificial sweat.

[0044] 0.17 g of magnesium chloride, 0.15 g of calcium chloride, 0.76 g of potassium dihydrogen phosphate, 0.53 g of calcium carbonate, 0.33 g of sodium chloride, and 0.75 g of potassium chloride were weighed separately in 900 mL of pure water, the pH was adjusted to 6.8 with 1% hydrochloric acid solution, and then the volume was adjusted to 1 L to serve as artificial simulated saliva.

[0045] (4) Pretreatment method:

[0046] (4.a) Pretreatment: Toys were used as test samples and pretreated according to the standard GB / T 38420-2019 "Determination of migration of bisphenol A in toy polycarbonate and polysulfone materials - High performance liquid chromatography-tandem mass spectrometry". 2 The toy is exposed to 10mL of artificial simulated liquid for migration test, and the toy is cut into 1cm 2 Small pieces or cut directly into 10cm 2 , take 10cm 2 Immerse the toy sample in artificial simulated liquid (artificial simulated sweat or artificial simulated saliva) at room temperature for 2 hours. Vortex once every 15 minutes for 30 seconds each time during the immersion process. The obtained immersion solution is the pretreatment solution;

[0047] (4.b) PAEs enrichment: 50 mL of the pretreatment solution was transferred to a glass centrifuge tube, and 100 mg of Fe₃O₄@SiO₂@UiO-67 was added. Adsorption was allowed to proceed for 20 min, with vortexing every 5 min for 30 s. The soaking solution was discarded under an external magnetic field, and 2 mL of acetonitrile was added for desorption. Desorption was allowed to proceed for 20 min, with vortexing every 5 min for 30 s. The acetonitrile eluate was removed under an external magnetic field, dehydrated with an appropriate amount of anhydrous sodium sulfate, filtered through a 0.22 μm membrane, and analyzed by gas chromatography-mass spectrometry.

[0048] (5) Gas chromatography-mass spectrometry detection:

[0049] (5.a) Chromatographic conditions: carrier gas: helium with a purity greater than or equal to 99.999%; flow rate: 1.0 mL / min; chromatographic column: HP-5 quartz capillary column, 30 m × 0.25 mm (id) × 0.25 μm; injection volume: 1.0 μL; temperature program: 60°C for 1 min, then increase to 220°C at 20°C / min, hold for 4 min, then increase to 250°C at 5°C / min, hold for 1 min, then increase to 290°C at 20°C / min, hold for 5 min; injection mode: splitless injection; transfer line temperature: 280°C.

[0050] (5.b) Mass spectrometry conditions: The mass spectrometry ionization mode was electron bombardment ion source, the scanning mode was selected ion monitoring mode, the ionization energy was 70 eV, and the ion source temperature was 250°C.

[0051] (6) Qualitative and quantitative:

[0052] The sample extract and the standard working solution are measured according to the above-mentioned gas chromatography-mass spectrometry conditions. If the retention time of the target compound in the sample extract differs from the retention time of the corresponding standard substance by no more than ±0.5% or ±0.1 min; and the relative abundance of the monitoring ion of the measured component in the sample spectrum is compared with the relative abundance of the corresponding monitoring ion in the standard solution with similar concentration, and the relative abundance of each ion is consistent, and the allowable deviation of the abundance ratio does not exceed the range specified in Table 1, then it can be determined that the corresponding analyte to be measured is present in the sample.

[0053] Table 2 Maximum allowable deviation of relative ion abundance for qualitative confirmation

[0054]

[0055] Use the matrix external standard method for quantitative analysis. Based on the analyte concentration in the sample, select a matrix standard working solution with a similar response value for chromatographic analysis. The response values ​​of the analyte in both the matrix standard working solution and the test solution should be within the instrument's linear range. If the response value is outside the linear range, dilute with matrix blank solution and repeat the analysis.

[0056] Figure 1 is the total ion current chromatogram of phthalate ester compounds, from Figure 1 It can be seen that 26 phthalate compounds are effectively separated, and the detection of 26 different phthalate compounds can be completed simultaneously within 40 minutes.

[0057] The retention times, quantitative ions, and qualitative ions of the 26 phthalate ester compounds are shown in Table 3.

[0058] Table 3 Retention time and mass spectrometry parameter data of phthalate compounds

[0059]

[0060]

[0061] (7) Blank test:

[0062] Experiments should be conducted using glassware whenever possible, avoiding plastic droppers and test tubes. Chromatographically pure reagents should be used. Before the experiment, glassware should be rinsed multiple times with ultrapure water, then baked in a muffle furnace for 2 hours and cooled to room temperature before use. A blank test should be performed between each run to ensure that the blank background value is below the limit of quantification for the corresponding compound.

[0063] (8) Detection limit and quantification limit:

[0064] The quantification limit of this method is 0.05 mg / L for DMP, DEP, DIPrP, DAP, DPrP, DIBP, DBP, DMEP, BMPP, DEEP, DPP, DHXP, BBP, DBEP, DCHP, DHP, DEHP, DPhP, DNOP, DBzP, DNP, DnDP, DnIPP, DIPP, DOTP, and DOIP.

[0065] Under optimized experimental conditions, a series of standard working solutions were tested. With the mass concentration of the substance as the abscissa and the peak area as the ordinate, the 26 phthalates showed good linear relationships within their respective ranges. The detection limits and quantification limits of various phthalates were calculated based on 3 times the signal-to-noise ratio and 10 times the signal-to-noise ratio, as shown in Table 4.

[0066] Table 4 Linear equations, correlation coefficients, detection limits and quantification limits of phthalate ester compounds

[0067]

[0068] (9) Method recovery and precision:

[0069] High, medium and low concentration standard solutions were quantitatively added to the sample, and the recovery test analysis was performed according to the above detection steps. As shown in Table 5, the recovery rate of each phthalate ester should be in the range of 80-120%.

[0070] In the same laboratory, the same operator uses the same equipment and follows the same test procedures. As shown in Table 5, the precision of 6 independent test results obtained by testing the same test object independently within a short period of time is less than 10%.

[0071] Table 5 Spiked recovery and precision data of phthalate ester compounds

[0072]

[0073]

[0074]

[0075] Example 2

[0076] Testing of children's toys on the market mainly found two phthalate compounds, DIBP and DEHP. After treatment and determination according to the experimental conditions, the migration amounts of DIBP and DEHP were 200μg / L to 1500μg / L.

[0077] The embodiments described above provide a detailed description of the technical solutions of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, supplements or similar substitutions made within the scope of the principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for analyzing the migration of phthalates in a sample enriched with a magnetic MOF material, characterized in that: The following steps are involved: (1) Pre-treating the sample to be tested so that potential phthalates in the sample to be tested migrate into a pre-treatment solution; the sample to be tested is a toy; the pre-treatment solution is prepared by soaking the toy sample in an artificial simulated solution at room temperature for ≥ 2 hours, with vortexing during the soaking process, and the resulting soaking solution is the pre-treatment solution; the artificial simulated solution is artificial simulated sweat or artificial simulated saliva; (2) mixing the magnetic MOF material with the pretreatment liquid and adsorbing the phthalates therein, then eluting the phthalates from the magnetic MOF material with an eluent, collecting the eluent, dehydrating the filter membrane, and then performing gas chromatography-mass spectrometry detection; the eluent is acetonitrile; The magnetic MOF material is Fe3O4@SiO2@UiO-67, which is a composite adsorbent of Fe3O4 coated with SiO2 on the surface and loaded with a metal organic framework UiO-67; in Fe3O4@SiO2@UiO-67, the mass ratio of Fe3O4 coated with SiO2 on the surface to the metal organic framework UiO-67 is 1:5-10; Fe3O4 is added to an ethanol solution, and then Ammonia water was added, and tetraethyl orthosilicate was added dropwise and stirred to react thoroughly. The reactant was washed with anhydrous ethanol and water and then dried in vacuo to obtain Fe3O4@SiO2. The obtained Fe3O4@SiO2 was dispersed in N,N'-dimethylformamide solution, and zirconium chloride, 4,4'-biphenyldicarboxylic acid and acetic acid solutions were added respectively. The mixture was heated at 120°C in a reactor for 24 hours. After the mixture was heated to room temperature, Fe3O4@SiO2@UiO-67 was separated by magnetic separation. The gas chromatography-mass spectrometry detection conditions are as follows: helium carrier gas at a flow rate of 1.0 mL / min; HP-5 quartz capillary column; injection volume 1.0 µL; temperature program: 60°C for 1 min, then increase to 220°C at 20°C / min, hold for 4 min, then increase to 250°C at 5°C / min, hold for 1 min, then increase to 290°C at 20°C / min, hold for 5 min; splitless injection; transfer line temperature 280°C; mass spectrometry ionization mode: electron impact ionization source, scan mode: selected ion monitoring mode, ionization energy 70 eV; ion source temperature 250°C-280°C; The phthalates include dimethyl phthalate, diethyl phthalate, diisopropyl phthalate, diallyl phthalate, dipropyl phthalate, diisobutyl phthalate, dibutyl phthalate, di(2-methoxy)ethyl phthalate, di(4-methyl-2-pentyl)phthalate, di(2-ethoxy)ethyl phthalate, dipentyl phthalate, dihexyl phthalate, Butyl benzyl phthalate, di(2-butoxy)ethyl phthalate, dicyclohexyl phthalate, diheptyl phthalate, di(2-ethyl)hexyl phthalate, diphenyl phthalate, di-n-octyl phthalate, dibenzyl phthalate, dinonyl phthalate, didecyl phthalate, n-pentyl isopentyl phthalate, diisopentyl phthalate, dioctyl terephthalate, and dioctyl isophthalate.

2. The method for analyzing the migration amount of phthalates in a magnetic MOF material enriched sample according to claim 1, wherein: In step (2), the ratio of the magnetic MOF material to the pretreatment solution is 50-150 mg:50 mL.

3. The method for analyzing the migration amount of phthalates in a magnetic MOF material enriched sample according to claim 1, wherein: In step (2), the adsorption time is 15-45 min.

4. The method for analyzing the migration amount of phthalates in a magnetic MOF material enriched sample according to claim 1, wherein: 50-150 mg of magnetic MOF material corresponds to 1-5 mL of eluent.

5. The method for analyzing the migration amount of phthalates in a magnetic MOF material enriched sample according to claim 1, characterized in that: The eluate was dehydrated with anhydrous sodium sulfate.

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