Method for simultaneously determining migration volumes of three hindered amine light stabilizers in plastic product for food contact

Abstract

The invention discloses a method for simultaneously determining migration volumes of three hindered amine light stabilizers by high performance liquid chromatography-tandem mass spectrometry, and belongs to the technical field of chemical detection. The three hindered amine light stabilizers are selected from plastic products for food contact, and are respectively a hindered amine light stabilizer 770, a hindered amine light stabilizer 944 and a hindered amine light stabilizer 3346. The method disclosed by the invention is simple and convenient to operate, has good accuracy and precision, and can meet the daily detection requirements of migration volumes of the hindered amine light stabilizer 770, the hindered amine light stabilizer 944 and the hindered amine light stabilizer 3346 in plastic products for food contact.

Description

Technical Field

[0001] The invention belongs to the technical field of chemical detection and relates to a method for simultaneously determining the migration amounts of three hindered amine light stabilizers in food contact plastic products. Background Art

[0002] Hindered amine light stabilizers are the most promising new type of high-efficiency light stabilizers in recent years. They have the advantages of good light stability, low migration and low coloration. The average annual demand growth rate in the world is 20% to 30%. At present, the national standard GB9685-2016 "National Food Safety Standard for the Use of Additives in Food Contact Materials and Products" stipulates that the maximum usage of di(2,2,6,6-tetramethyl-4-piperidinyl) sebacate (hindered amine light stabilizer 770) in food contact PE, PP, PS, AS, ABS plastic materials and products is 0.5%, and the maximum usage in adhesives for food contact materials and products is 0.1%. The polymer of N,N'-di-(2,2,6,6-tetramethylpiperidinyl-4-yl)-1,6-hexanediamine and 4-dichloro-6-4-morpholinyl-1,3,5-triazine (hindered amine light stabilizer 3346) is used in food contact PP, PE plastic materials and products at a maximum amount of 0.3%, and the specific migration limit index is 5 mg / kg. Poly[[6-[(1,1,3,3-tetramethylbutyl)amino]-1,3,5-triazine-2,4-diyl][(2,2,6,6-tetramethyl-4-piperidinyl)imino]-1,6-hexanediyl[(2,2,6,6-tetramethyl-4-piperidinyl)imino]] (hindered amine light stabilizer 944) is used in food contact PP, PE plastic materials and products at a maximum amount of 0.3%, and the specific migration limit index is 3 mg / kg.

[0003] At present, technical standards for the determination of hindered amine light stabilizers have not been issued domestically or internationally. Hindered amine light stabilizers usually do not have strong ultraviolet absorption groups and are not suitable for direct detection with ultraviolet detectors. They need to be derivatized before they can be analyzed by liquid chromatography. Literature reports the use of p-nitrobenzoyl chloride to derivatize hindered amine light stabilizer 944, high performance liquid chromatography separation, diode array detector detection, quantitative wavelength of 230nm, and a lower limit of determination of 0.1mol / L. Moreover, due to the large steric hindrance of the N group, it also poses a huge challenge to the derivatization conditions, and the derivatization operation is time-consuming and labor-intensive. Due to the high boiling point of this type of compound, it is not suitable for analysis by gas chromatography and gas chromatography-mass spectrometry. Liquid chromatography-tandem mass spectrometry has high sensitivity, does not require derivatization, and can be directly determined. It can scan a wide m / z range and is suitable for analyzing hindered amine light stabilizers with larger molecular weights.

[0004] However, the current research mainly focuses on UV absorbers, such as benzotriazoles and benzophenones, etc. The research on the determination of the migration amount of hindered amine light stabilizers in food contact materials by liquid chromatography-tandem mass spectrometry has just started.

[0005] Therefore, how to develop a method for simultaneously determining the migration amounts of three hindered amine light stabilizers in food contact plastic products is an urgent problem to be solved by those skilled in the art. Summary of the invention

[0006] In view of this, the present invention provides a method for simultaneously determining the migration amounts of three hindered amine light stabilizers in food contact plastic products.

[0007] In order to achieve the above object, the present invention adopts the following technical solution:

[0008] A method for simultaneously determining the migration amounts of three hindered amine light stabilizers by high performance liquid chromatography-tandem mass spectrometry, wherein the three hindered amine light stabilizers are from food contact plastic products, namely hindered amine light stabilizer 770, hindered amine light stabilizer 944, and hindered amine light stabilizer 3346, and the method comprises the following steps:

[0009] The sample to be tested and the standard solution were respectively taken for testing, and the chromatographic conditions were as follows: a C18 column was used as the chromatographic column, the mobile phase system was a mobile phase A of a 0.1% volume fraction of formic acid aqueous solution, the mobile phase B was methanol, and the gradient elution program was: 0-5min, 50% B; 5-8min, 50%-80% B; 8-12min, 80% B; 12-12.1min, 80%-100% B; 12.1-15min, 100% B; 15-15.1min, 100%-50% B; 15.1-18min, 50% B; the column temperature was 35°C; the flow rate was 0.20mL / min; the injection volume was 3μL;

[0010] The mass spectrometry conditions were as follows: electrospray ion source, positive ion scanning mode, ion source temperature 100°C; capillary voltage 4000V; drying gas nitrogen, temperature 350°C, flow rate 10L / min; nebulizing gas pressure 138kPa; collision gas was high-purity nitrogen; and multiple reaction monitoring.

[0011] Furthermore, the above-mentioned chromatographic column is an ACQUITY UPLC BEH C18 chromatographic column with specifications of 100 mm×2.1 mm and 1.7 μm.

[0012] Furthermore, the preparation method of the above-mentioned sample to be tested includes the following steps: using water, 4% by volume acetic acid solution, 10% by volume ethanol solution, 20% by volume ethanol solution, 50% by volume ethanol solution or isooctane as food simulants, and subjecting food contact plastic products to a migration test in accordance with GB31604.1-2023 "General Rules for Migration Tests of Food Contact Materials and Products, National Food Safety Standard"; water, 4% by volume acetic acid solution, and 20% by volume ethanol solution obtained by the migration test are used as food simulants. The 10% ethanol solution, 20% ethanol solution and 50% ethanol solution were filtered through a 0.22 μm filter membrane, and the filtrate was used for instrument determination; 2 mL of the isooctane soaking solution obtained by the migration test was measured, and 2 mL of a mixed solution of methanol, acetic acid and water was added, and the mixture was shaken and extracted for 30 seconds. The volume ratio of methanol, acetic acid and water in the mixed solution of methanol, acetic acid and water was 50:0.4:50. After standing for stratification, the lower layer of solution was taken, and after filtering through a 0.22 μm filter membrane, the filtrate was used for instrument determination.

[0013] Further, the preparation method of the above standard solution comprises the following steps:

[0014] (1) Hindered amine light stabilizer 770, Hindered amine light stabilizer 944, and Hindered amine light stabilizer 3346 were prepared into a standard stock solution 1 with a mass concentration of 100 mg / L using methanol;

[0015] The hindered amine light stabilizer 770, hindered amine light stabilizer 944 and hindered amine light stabilizer 3346 were respectively prepared with isooctane to prepare a standard stock solution 2 with a mass concentration of 100 mg / L;

[0016] The standard stock solution 1 of hindered amine light stabilizer 770 and the standard stock solution 1 of hindered amine light stabilizer 3346 were diluted with methanol to form a standard intermediate solution 1 with a mass concentration of 10 mg / L;

[0017] The standard stock solution 2 of hindered amine light stabilizer 770 and the standard stock solution 2 of hindered amine light stabilizer 3346 are diluted with isooctane to form a standard intermediate solution 2 with a mass concentration of 10 mg / L;

[0018] (2) Water-based food simulant matching standard solution series: Take 0.025mL, 0.05mL, 0.1mL, 0.25mL, and 0.5mL of hindered amine light stabilizer 770 standard intermediate solution 1, first add 0.05mL, 0.1mL, 0.2mL, 0.5mL, and 1.0mL of hindered amine light stabilizer 3346 standard intermediate solution 1 in sequence, and then add 0.05mL, 0.1mL, 0.2mL, 0.5mL, and 1.0mL of hindered amine light stabilizer 944 standard stock solution 1 in sequence into a 10mL volumetric flask, and dilute with water step by step to prepare hindered amine light stabilizer 770 with a mass concentration of 0.025mg / L, 0.05mg / L, 0.1mL, and 0.2mg / L, respectively. g / L, 0.25mg / L, 0.5mg / L, the mass concentration of hindered amine light stabilizer 3346 is 0.05mg / L, 0.1mg / L, 0.2mg / L, 0.5mg / L, 1mg / L, the mass concentration of hindered amine light stabilizer 944 is 0.5mg / L, 1mg / L, 2mg / L, 5mg / L, 10mg / L, shake well for use; in the same way, use 10% ethanol solution by volume, 20% ethanol solution by volume, 50% ethanol solution by volume and 4% acetic acid solution by volume to dilute step by step to prepare the other 4 kinds of water-based food simulants matching standard solution series for instrument determination;

[0019] Isooctane matching standard solution series: Take 0.025mL, 0.05mL, 0.1mL, 0.25mL, 0.5mL of hindered amine light stabilizer 770 standard intermediate solution 2 respectively, first add 0.05mL, 0.1mL, 0.2mL, 0.5mL, 1.0mL of hindered amine light stabilizer 3346 standard intermediate solution 2 in sequence, then add 0.05mL, 0.1mL, 0.2mL, 0.5mL, 1.0mL of hindered amine light stabilizer 944 standard stock solution 2 in sequence in a 10mL volumetric flask, and dilute step by step with isooctane to prepare hindered amine light stabilizer 770 with mass concentrations of 0.025mg / L, 0.05mg / L, 0.1mg / L respectively. , 0.25mg / L, 0.5mg / L, the mass concentrations of hindered amine light stabilizer 3346 are 0.05mg / L, 0.1mg / L, 0.2mg / L, 0.5mg / L, 1mg / L, the mass concentrations of hindered amine light stabilizer 944 are 0.5mg / L, 1mg / L, 2mg / L, 5mg / L, 10mg / L respectively. After shaking, take 2mL, add 2mL of a mixed solution of methanol, acetic acid and water, and shake for 30s. The volume ratio of methanol, acetic acid and water in the mixed solution of methanol, acetic acid and water is 50:0.4:50. Let it stand for stratification, take the solution, filter it through a 0.22μm filter membrane, and the filtrate is used for instrument determination.

[0020] The beneficial effects of the present invention are as follows: the HALS 770 in different food simulants of the present invention has a linear relationship with its peak area within the mass concentration range of 0.025-0.5 mg / L, the HALS 944 has a linear relationship with its peak area within the mass concentration range of 0.5-10 mg / L, and the HALS 3346 has a linear relationship with its peak area within the mass concentration range of 0.05-1 mg / L. The quantitative limit (10S / N) is 0.001-0.15 mg / L. The spiked recovery rates at three concentration levels are 85.5%-108.5%, and the relative standard deviation (n=6) of the measured values ​​is 2.5%-10.0%. It shows that the method is simple to operate, has good accuracy and precision, and can meet the daily detection needs of the migration amount of HALS 770, HALS 944 and HALS 3346 in food contact plastic products. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 MRM chromatograms of (a) 0.025 mg / L HALS 770, (b) 0.05 mg / L HALS 3346, and (c) 0.5 mg / L HALS 944 in water.

[0022] Figure 2 MRM chromatograms of (a) 0.025 mg / L HALS 770, (b) 0.05 mg / L HALS 3346, and (c) 0.5 mg / L HALS 944 in 4% acetic acid solution.

[0023] Figure 3 MRM chromatograms of (a) 0.025 mg / L HALS 770, (b) 0.05 mg / L HALS 3346, and (c) 0.5 mg / L HALS 944 in 10% ethanol solution.

[0024] Figure 4 MRM chromatograms of (a) 0.025 mg / L HALS 770, (b) 0.05 mg / L HALS 3346, and (c) 0.5 mg / L HALS 944 in 20% ethanol solution.

[0025] Figure 5 MRM chromatograms of (a) 0.025 mg / L HALS 770, (b) 0.05 mg / L HALS 3346, and 0.5 mg / L HALS 944 in 50% ethanol solution.

[0026] Figure 6MRM chromatograms of (a) 0.025 mg / L HALS 770, (b) 0.05 mg / L HALS 3346, and (c) 0.5 mg / L HALS 944 in isooctane. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] Example 1

[0029] A method for simultaneously determining the migration amounts of three hindered amine light stabilizers by high performance liquid chromatography-tandem mass spectrometry, wherein the three hindered amine light stabilizers are from food contact plastic products, namely hindered amine light stabilizer 770, hindered amine light stabilizer 944, and hindered amine light stabilizer 3346, and the method comprises the following steps:

[0030] The preparation method of the sample to be tested comprises the following steps: using water, 4% by volume acetic acid solution, 10% by volume ethanol solution, 20% by volume ethanol solution, 50% by volume ethanol solution or isooctane as food simulants, and subjecting food contact plastic products to a migration test in accordance with GB31604.1-2023 "General Rules for Migration Tests of Food Contact Materials and Products, National Food Safety Standard"; water, 4% by volume acetic acid solution, 10% by volume ethanol solution, 20% by volume ethanol solution, 50% by volume ethanol solution or isooctane obtained through the migration test. % ethanol solution, 20% ethanol solution by volume, and 50% ethanol solution by volume were filtered through a 0.22 μm filter membrane, and the filtrate was used for instrument determination; 2 mL of the isooctane soaking solution obtained by the migration test was measured, and 2 mL of a mixed solution of methanol, acetic acid and water was added, and the mixture was shaken and extracted for 30 seconds. The volume ratio of methanol, acetic acid and water in the mixed solution of methanol, acetic acid and water was 50:0.4:50. The mixture was allowed to stand for stratification, and the lower layer of solution was taken. After filtering through a 0.22 μm filter membrane, the filtrate was used for instrument determination.

[0031] The preparation method of the standard solution comprises the following steps:

[0032] (1) Hindered amine light stabilizer 770, Hindered amine light stabilizer 944, and Hindered amine light stabilizer 3346 were prepared into a standard stock solution 1 with a mass concentration of 100 mg / L using methanol;

[0033] The hindered amine light stabilizer 770, hindered amine light stabilizer 944 and hindered amine light stabilizer 3346 were respectively prepared with isooctane to prepare a standard stock solution 2 with a mass concentration of 100 mg / L;

[0034] The standard stock solution 1 of hindered amine light stabilizer 770 and the standard stock solution 1 of hindered amine light stabilizer 3346 were diluted with methanol to form a standard intermediate solution 1 with a mass concentration of 10 mg / L;

[0035] The standard stock solution 2 of hindered amine light stabilizer 770 and the standard stock solution 2 of hindered amine light stabilizer 3346 are diluted with isooctane to form a standard intermediate solution 2 with a mass concentration of 10 mg / L;

[0036] (2) Water-based food simulant matching standard solution series: Take 0.025mL, 0.05mL, 0.1mL, 0.25mL, and 0.5mL of hindered amine light stabilizer 770 standard intermediate solution 1, first add 0.05mL, 0.1mL, 0.2mL, 0.5mL, and 1.0mL of hindered amine light stabilizer 3346 standard intermediate solution 1 in sequence, and then add 0.05mL, 0.1mL, 0.2mL, 0.5mL, and 1.0mL of hindered amine light stabilizer 944 standard stock solution 1 in sequence into a 10mL volumetric flask, and dilute with water step by step to prepare hindered amine light stabilizer 770 with a mass concentration of 0.025mg / L, 0.05mg / L, 0.1mL, and 0.2mg / L, respectively. g / L, 0.25mg / L, 0.5mg / L, the mass concentration of hindered amine light stabilizer 3346 is 0.05mg / L, 0.1mg / L, 0.2mg / L, 0.5mg / L, 1mg / L, the mass concentration of hindered amine light stabilizer 944 is 0.5mg / L, 1mg / L, 2mg / L, 5mg / L, 10mg / L, shake well for use; in the same way, use 10% ethanol solution by volume, 20% ethanol solution by volume, 50% ethanol solution by volume and 4% acetic acid solution by volume to dilute step by step to prepare the other 4 kinds of water-based food simulants matching standard solution series for instrument determination;

[0037] Isooctane matching standard solution series: Take 0.025mL, 0.05mL, 0.1mL, 0.25mL, 0.5mL of hindered amine light stabilizer 770 standard intermediate solution 2 respectively, first add 0.05mL, 0.1mL, 0.2mL, 0.5mL, 1.0mL of hindered amine light stabilizer 3346 standard intermediate solution 2 in sequence, then add 0.05mL, 0.1mL, 0.2mL, 0.5mL, 1.0mL of hindered amine light stabilizer 944 standard stock solution 2 in sequence in a 10mL volumetric flask, and dilute step by step with isooctane to prepare hindered amine light stabilizer 770 with mass concentrations of 0.025mg / L, 0.05mg / L, 0.1mg / L respectively. , 0.25mg / L, 0.5mg / L, the mass concentrations of hindered amine light stabilizer 3346 are 0.05mg / L, 0.1mg / L, 0.2mg / L, 0.5mg / L, 1mg / L, the mass concentrations of hindered amine light stabilizer 944 are 0.5mg / L, 1mg / L, 2mg / L, 5mg / L, 10mg / L respectively. After shaking, take 2mL, add 2mL of a mixed solution of methanol, acetic acid and water, and shake for 30s. The volume ratio of methanol, acetic acid and water in the mixed solution of methanol, acetic acid and water is 50:0.4:50. Let it stand for stratification, take the solution, filter it through a 0.22μm filter membrane, and the filtrate is used for instrument determination.

[0038] The sample to be tested and the standard solution were taken for testing respectively, and the chromatographic conditions were as follows: an ACQUITY UPLC BEH C18 column (specification: 100 mm×2.1 mm, 1.7 μm) was used as the chromatographic column, the mobile phase system was mobile phase A: a 0.1% volume fraction of formic acid aqueous solution, mobile phase B: methanol, and the gradient elution program was: 0-5 min, 50% B; 5-8 min, 50%-80% B; 8-12 min, 80% B; 12-12.1 min, 80%-100% B; 12.1-15 min, 100% B; 15-15.1 min, 100%-50% B; 15.1-18 min, 50% B; the column temperature was 35° C.; the flow rate was 0.20 mL / min; the injection volume was 3 μL;

[0039] Table 1 Gradient elution program

[0040]

[0041] The mass spectrometry conditions were as follows: electrospray ion source, positive ion scanning mode, ion source temperature 100°C; capillary voltage 4000V; drying gas nitrogen, temperature 350°C, flow rate 10L / min; nebulizing gas pressure 138kPa; collision gas was high-purity nitrogen; and multiple reaction monitoring.

[0042] The multiple reaction monitoring (MRM) acquisition mode was used for qualitative and quantitative analysis. The parameters of parent ion, daughter ion, fragmentation voltage, collision energy, etc. are shown in Table 2.

[0043] Table 2 Mass spectrometry acquisition parameters in multiple reaction monitoring mode

[0044]

[0045] *Quantitative ion

[0046] Experimental Example 1: Selection of Chromatographic Column

[0047] The chemical structure of hindered amine light stabilizers 770, 944, and 3346 contains piperidine groups, so it is advisable to use an acidic mobile phase. The experiment investigated the effects of BET C18 column (2.1×100mm, 1.7μm), BET C8 column (2.1×150mm, 1.7μm), BET HILIC column (2.1×50mm, 1.7μm), and amino column (4.6×250mm, 5μm) on the separation of the three targets. Using the BET HILIC column (95% acetonitrile-60% acetonitrile gradient elution), the peaks of the three targets were broadened and the retention times were close. The target can only be eluted when there is a high proportion of aqueous phase, which is speculated to be caused by the strong interaction between the target and polar fixation. Using the amino column, the sensitivity of the three targets was significantly reduced. Using the BET C8 column and the BET C18 column, the retention time, sensitivity and peak shape of the three targets were close. Considering the popularity, the C18 column was selected here.

[0048] Experimental Example 2: Selection of mass spectrometry conditions

[0049] The hindered amine light stabilizers 770, 944, and 3346 were analyzed by triple quadrupole mass spectrometry. Considering that the chemical structure of the target contains a piperidine group, an acidic mobile phase system was used and the ESI+ mode was used for scanning. First, a full scan (SCAN) was performed in the range of m / z35 to 2000. The mass spectra of the three target hindered amine light stabilizers 770, 944, and 3346 were obtained in the SCAN mode. In the mass spectrum of hindered amine light stabilizer 770, it can be seen that m / z481.4 is [M+H]+, and m / z241.2 is [M+2H]2+. In the mass spectrum of hindered amine light stabilizer 944, it can be seen that the most abundant m / z599.4 can be seen. In the mass spectrum of hindered amine light stabilizer 3346, it can be seen that the most abundant m / z447.3 can be seen. By optimizing the fragmentation voltage, collision energy and other parameters, the two daughter ion pairs with the highest and second highest response values ​​were finally selected as the quantitative and qualitative ion pairs in the MRM mode. Under the optimized instrument working conditions, the MRM chromatograms of 0.025 mg / L hindered amine light stabilizer 770, 0.05 mg / L hindered amine light stabilizer 3346, and 0.5 mg / L hindered amine light stabilizer 944 in different food simulants are shown in the following figure. Figure 1 shown.

[0050] Test Example 3: Treatment of isooctane soaking liquid

[0051] In the reversed phase liquid chromatography system, the isooctane solution cannot be directly injected. The hindered amine light stabilizers 770, 944, and 3346 in the isooctane soaking solution must be transferred to an organic phase solution that is miscible with water for injection. Two methods were investigated. Method 1 is to take 2 mL of isooctane standard solution (the mass concentrations of hindered amine light stabilizers 770, 944, and 3346 are 0.5 mg / L, 1 mg / L, and 10 mg / L, respectively), rotary evaporate at 50°C (5000 Pa) until nearly dry, add 2 mL of methanol-water solution (50 mL of methanol and 0.4 mL of acetic acid in 50 mL of water), shake and extract for 30 seconds, let it stand, and after stratification, take the lower layer of methanol-water solution, filter it through a 0.22 μm organic filter membrane, and analyze it with an instrument. Method 2 is to take 2mL of isooctane standard solution (the mass concentrations of hindered amine light stabilizers 770, 944, and 3346 are 0.5mg / L, 1mg / L, and 10mg / L, respectively), add 2mL of methanol-water solution (50mL of methanol and 0.4mL of acetic acid are added to 50mL of water), shake for 30s, let stand for 10min, take the lower layer of methanol-water solution, filter it, and analyze it on the machine. The results show that there is no significant difference in the recovery rate of the two methods. Considering the simplicity of operation, method 2 is selected.

[0052] Test Example 4: Standard curve and lower limit of determination

[0053] The standard solution series of hindered amine light stabilizers 770, 944 and 3346 matching each food simulant were determined according to the instrument working conditions. The working curves were plotted with mass concentration as the abscissa and the corresponding peak area as the ordinate. The linear range of each working curve and the determination lower limit calculated with 10 times the signal-to-noise ratio (S / N) are shown in Table 3.

[0054] Table 3 Linear parameters and lower limits of determination

[0055]

[0056] As shown in Table 3, the quantitative limits (10S / N) of hindered amine light stabilizers 770, 944, and 346 in the six food simulants are 0.001-0.15 mg / L, which meets the detection requirements.

[0057] Test Example 5: Precision and Recovery Test

[0058] The blank actual samples, i.e., the samples without the target substance, were processed according to the test method. The standard solutions of hindered amine light stabilizers 770, 944, and 3346 were added to the obtained food simulant soaking solution. The spike recovery test at three concentration levels was carried out. Each concentration level was measured six times in parallel. The recovery rate and the relative standard deviation (RSD) of the measured values ​​were calculated. The results are shown in Table 4.

[0059] Table 4 Precision and recovery test results (n = 6)

[0060]

[0061]

[0062] As shown in Table 4, the recoveries of the three concentration levels of hindered amine light stabilizers 770, 944 and 346 in the six food simulants were 85.5% to 108.5%, and the relative standard deviations (n=6) of the measured values ​​were 2.5% to 10.0%, indicating that this method has good accuracy and precision.

[0063] The disclosed embodiments are described to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for simultaneously determining the migration amounts of three hindered amine light stabilizers by high performance liquid chromatography-tandem mass spectrometry, characterized in that: The three hindered amine light stabilizers are from food contact plastic products, namely hindered amine light stabilizer 770, hindered amine light stabilizer 944, and hindered amine light stabilizer 3346. The method comprises the following steps: The sample to be tested and the standard solution were respectively taken for testing, and the chromatographic conditions were as follows: a C18 column was used as the chromatographic column, the mobile phase system was a mobile phase A of a 0.1% volume fraction of formic acid aqueous solution, the mobile phase B was methanol, and the gradient elution program was: 0-5min, 50% B; 5-8min, 50%-80% B; 8-12min, 80% B; 12-12.1min, 80%-100% B; 12.1-15min, 100% B; 15-15.1min, 100%-50% B; 15.1-18min, 50% B; the column temperature was 35°C; the flow rate was 0.20mL / min; the injection volume was 3μL; The mass spectrometry conditions were as follows: electrospray ion source, positive ion scanning mode, ion source temperature 100°C; capillary voltage 4000V; drying gas nitrogen, temperature 350°C, flow rate 10L / min; nebulizing gas pressure 138kPa; collision gas was high-purity nitrogen; and multiple reaction monitoring.

2. The method for simultaneously determining the migration amounts of three hindered amine light stabilizers by high performance liquid chromatography-tandem mass spectrometry according to claim 1, characterized in that: The chromatographic column is an ACQUITY UPLC BEH C18 chromatographic column with specifications of 100 mm×2.1 mm and 1.7 μm.

3. The method for simultaneously determining the migration amounts of three hindered amine light stabilizers by high performance liquid chromatography-tandem mass spectrometry according to claim 1, characterized in that: The preparation method of the sample to be tested comprises the following steps: using water, 4% by volume acetic acid solution, 10% by volume ethanol solution, 20% by volume ethanol solution, 50% by volume ethanol solution or isooctane as food simulants, and subjecting food contact plastic products to a migration test in accordance with GB31604.1-2023 "General Rules for Migration Tests of Food Contact Materials and Products, National Food Safety Standard"; water, 4% by volume acetic acid solution, 10% by volume ethanol solution, 20% by volume ethanol solution, 50% by volume ethanol solution or isooctane as food simulants; 0% ethanol solution, 20% ethanol solution by volume, and 50% ethanol solution by volume were filtered through a 0.22 μm filter membrane, and the filtrate was used for instrument determination; 2 mL of the isooctane soaking solution obtained by the migration test was measured, and 2 mL of a mixed solution of methanol, acetic acid and water was added, and the mixture was shaken and extracted for 30 seconds. The volume ratio of methanol, acetic acid and water in the mixed solution of methanol, acetic acid and water was 50:0.4:

50. After standing for stratification, the lower layer of solution was taken, and after filtering through a 0.22 μm filter membrane, the filtrate was used for instrument determination.

4. The method for simultaneously determining the migration amounts of three hindered amine light stabilizers by high performance liquid chromatography-tandem mass spectrometry according to claim 1, characterized in that: The preparation method of the standard solution comprises the following steps: (1) Hindered amine light stabilizer 770, Hindered amine light stabilizer 944, and Hindered amine light stabilizer 3346 were prepared into a standard stock solution 1 with a mass concentration of 100 mg / L using methanol; The hindered amine light stabilizer 770, hindered amine light stabilizer 944 and hindered amine light stabilizer 3346 were respectively prepared with isooctane to prepare a standard stock solution 2 with a mass concentration of 100 mg / L; The standard stock solution 1 of hindered amine light stabilizer 770 and the standard stock solution 1 of hindered amine light stabilizer 3346 were diluted with methanol to form a standard intermediate solution 1 with a mass concentration of 10 mg / L; The standard stock solution 2 of hindered amine light stabilizer 770 and the standard stock solution 2 of hindered amine light stabilizer 3346 are diluted with isooctane to form a standard intermediate solution 2 with a mass concentration of 10 mg / L; (2) Water-based food simulant matching standard solution series: Take 0.025mL, 0.05mL, 0.1mL, 0.25mL, and 0.5mL of hindered amine light stabilizer 770 standard intermediate solution 1, first add 0.05mL, 0.1mL, 0.2mL, 0.5mL, and 1.0mL of hindered amine light stabilizer 3346 standard intermediate solution 1 in sequence, and then add 0.05mL, 0.1mL, 0.2mL, 0.5mL, and 1.0mL of hindered amine light stabilizer 944 standard stock solution 1 in sequence into a 10mL volumetric flask, and dilute with water step by step to prepare hindered amine light stabilizer 770 with a mass concentration of 0.025mg / L, 0.05mg / L, 0.1mL, and 0.2mg / L, respectively. g / L, 0.25mg / L, 0.5mg / L, the mass concentration of hindered amine light stabilizer 3346 is 0.05mg / L, 0.1mg / L, 0.2mg / L, 0.5mg / L, 1mg / L, the mass concentration of hindered amine light stabilizer 944 is 0.5mg / L, 1mg / L, 2mg / L, 5mg / L, 10mg / L, shake well for use; in the same way, use 10% ethanol solution by volume, 20% ethanol solution by volume, 50% ethanol solution by volume and 4% acetic acid solution by volume to dilute step by step to prepare the other 4 kinds of water-based food simulants matching standard solution series for instrument determination; Isooctane matching standard solution series: Take 0.025mL, 0.05mL, 0.1mL, 0.25mL, 0.5mL of hindered amine light stabilizer 770 standard intermediate solution 2 respectively, first add 0.05mL, 0.1mL, 0.2mL, 0.5mL, 1.0mL of hindered amine light stabilizer 3346 standard intermediate solution 2 in sequence, then add 0.05mL, 0.1mL, 0.2mL, 0.5mL, 1.0mL of hindered amine light stabilizer 944 standard stock solution 2 in sequence in a 10mL volumetric flask, and dilute step by step with isooctane to prepare hindered amine light stabilizer 770 with mass concentrations of 0.025mg / L, 0.05mg / L, 0.1mg / L respectively. , 0.25mg / L, 0.5mg / L, the mass concentrations of hindered amine light stabilizer 3346 are 0.05mg / L, 0.1mg / L, 0.2mg / L, 0.5mg / L, 1mg / L, the mass concentrations of hindered amine light stabilizer 944 are 0.5mg / L, 1mg / L, 2mg / L, 5mg / L, 10mg / L respectively. After shaking, take 2mL, add 2mL of a mixed solution of methanol, acetic acid and water, and shake for 30s. The volume ratio of methanol, acetic acid and water in the mixed solution of methanol, acetic acid and water is 50:0.4:

50. Let it stand for stratification, take the solution, filter it through a 0.22μm filter membrane, and the filtrate is used for instrument determination.

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