Method for determining migration volume of octyl glycidyl ether in food contact material by using solid food simulant

Abstract

The invention provides a method for determining the migration volume of octyl glycidyl ether in a food contact material by using a solid food simulant, which comprises the following steps: carrying out a migration experiment on modified polyphenyl ether (MPPO) serving as the food simulant and the food contact material, and then efficiently extracting a migrated target object by using an ultrasonic-assisted supramolecular mixed solvent. According to the method, the migration volume of the octyl glycidyl ether is detected through GC-MS after filtration and extraction, the method is small in interference and high in sensitivity, the problem that a method for detecting the octyl glycidyl ether in the dry food simulant is lacked is solved, and a basis is provided for safety evaluation of the octyl glycidyl ether in a packaging material.

Description

Technical Field

[0001] The present invention belongs to the technical field of food detection, and particularly relates to a method for determining the migration amount of octyl glycidyl ether in food contact materials by using a solid food simulant. Background Art

[0002] Octyl glycidyl ether is a colorless and transparent volatile liquid, which is widely used in the fields of chemical industry, medicine, agriculture, etc., and is often used as a solvent, chemical reagent, lubricating oil, etc. Octyl ether is a volatile organic compound, which is easy to form an explosive mixture with oxygen in the air and is prone to explosion under conditions such as high temperature, fire source or electrostatic discharge. Long-term contact or inhalation of octyl glycidyl ether will cause harm to human health, and may cause symptoms such as headache, insomnia, lethargy, liver damage, etc. At the same time, octyl glycidyl ether may also cause environmental pollution and ecological imbalance. Octyl glycidyl ether has acute toxicity, and the LD50 value of rats by oral administration is 7800 mg / kg; it has mutagenicity, and the value of bacteria - Salmonella typhimurium is 100 ug / plate. The specific migration limit (SML) of octyl glycidyl ether is specified as not detectable (the detection limit is 0.01 mg / kg) in the Chinese standard GB 9685 - 2016.

[0003] At present, there is no reported detection method for the migration amount of octyl glycidyl ether in modified polyphenylene ether (MPPO). For small molecule substances similar to the target substance (octyl glycidyl ether), the currently reported detection methods mainly include headspace - gas chromatography, headspace - gas chromatography - mass spectrometry, etc. Among them, headspace - gas chromatography - mass spectrometry has very obvious advantages for the accurate qualitative and quantitative analysis of trace low - boiling compounds, and is often used for the qualitative confirmation and quantitative analysis of such substances. Existing research has shown that specific substances migrate in liquid simulants by diffusion, and the migration amount usually increases continuously with the increase of temperature and the extension of time; while MPPO, as a porous simulant, has a different migration mechanism from the former, and substances are transferred through the way of "adsorption - desorption". When the food expected to be contacted by the packaging material is dry, solid or oily food (such as milk powder cans, biscuit boxes, cake boxes, pizza boxes, etc.), selecting a liquid simulant cannot reflect the actual use scenario, while selecting MPPO as a solid food simulant can well simulate the actual use scenario. At present, the research on the migration law of MPPO at home and abroad is still very insufficient, especially there is little research on volatile substances, which cannot meet the increasingly strict regulatory or hygiene standard requirements. Summary of the Invention

[0004] The present invention provides a method for determining the migration amount of octyl glycidyl ether in food contact materials using a solid food simulant. Modified polyphenylene oxide (MPPO) is used as the food simulant to conduct a migration experiment with the food contact material, and then a supramolecular mixed solvent is used to efficiently extract the migrated octyl glycidyl ether. After filtration and extraction, GC-MS detection is carried out to determine the migration amount. This method has little interference and high sensitivity, solves the problem of the lack of detection methods for octyl glycidyl ether in dry food simulants, and provides a basis for the safety assessment of its use in packaging materials.

[0005] The present invention is realized through the following technical solutions:

[0006] A method for determining the migration amount of octyl glycidyl ether in food contact materials using a solid food simulant, comprising the following steps: Select modified polyphenylene oxide (MPPO) as the solid food simulant, conduct a migration experiment with the food contact material, add a supramolecular mixed solvent to the modified polyphenylene oxide after the migration experiment and perform ultrasonic-assisted extraction of the target substance. After filtration through quantitative filter paper, extract with n-hexane, take the upper layer solution and concentrate it by nitrogen blowing to obtain the test sample solution; respectively aspirate the test sample solution and the standard working solution for GC-MS detection, and use the external standard working curve method to determine the migration amount of octyl glycidyl ether;

[0007] The supramolecular mixed solvent, calculated by the total volume of 100%, comprises the following components: long-chain alkyl alcohol 4.28 - 7.13%, tetrahydrofuran 7.18 - 12.88%, and the balance water; the long-chain alkyl alcohol is selected from one of n-pentanol, n-hexanol, n-heptanol, n-octanol, n-nonanol, and n-decanol;

[0008] The conditions for the GC-MS detection are as follows: a) Chromatographic column: 6% cyanopropyl / phenyl 94% dimethyl polysiloxane capillary chromatographic column; b) Temperature programming: hold at 50°C for 0 min, rise to 100°C at 3°C / min, hold for 2 min; rise to 250°C at 25°C / min, hold for 1 min; c) Injection port temperature: 150°C; d) Column flow rate: 1.5 mL / min; e) Injection volume: 2 μL; f) Injection mode: split injection, split ratio 3:1; g) Ion source: electron impact ion source (EI); h) Ion source temperature: 230°C; i) Quadrupole mass analyzer temperature: 150°C; j) Transfer line temperature: 280°C; k) Ionization energy: 70 eV; l) Solvent delay: 5.0 min; m) Detection mode: SIM (selected ion monitoring mode).

[0009] Preferably, the long-chain alkyl alcohol is selected from n-nonanol.

[0010] Preferably, based on 100% of the total volume of the supramolecular mixed solvent, it comprises the following components: nonyl alcohol 5.71%, tetrahydrofuran 8.60%, and the balance is water.

[0011] Preferably, the specifications of the chromatographic column are 30m × 0.25mm × 1.4μm.

[0012] Preferably, in the selected ion monitoring mode, the qualitative ions (m / z): 70, 112, and the quantitative ion (m / z): 57.

[0013] Preferably, the preparation steps of the standard working solution are as follows: Weigh the octyl glycidyl ether standard product and prepare a standard stock solution of 1000 mg / L with n-hexane, then dilute it with methanol to a standard intermediate solution of 10 mg / L, and finally gradually dilute the standard intermediate solution with acetonitrile to prepare standard working solutions with concentrations of 0.020 mg / L, 0.040 mg / L, 0.080 mg / L, 0.10 mg / L, and 0.20 mg / L.

[0014] Preferably, the time of ultrasonic treatment is 15 min.

[0015] Preferably, in the migration experiment, MPPO is evenly covered on the food contact material in an amount of 4 g / dm 2 and then placed in an oven for the migration of the target substance.

[0016] The preparation of the test sample solution includes the following steps: Contact the sample with MPPO for the migration experiment. For bag-like samples, place the sample on a glass plate, cover it with the outer cover of a petri dish, cut along the edge of the outer cover with a paper cutter, and prepare 3 samples at the same time. Place them flat inside the inner covers of 3 petri dishes respectively, and calculate the surface area of the sample based on the area of the inner cover. Cover the surface of the sample evenly with MPPO in an amount of 4 g / dm 2 and cover it completely with the inner cover without spilling outside; for container-like samples, measure the bottom diameter of the container, calculate the bottom area, and cover the bottom of the container evenly with MPPO in an amount of 4 g / dm 2 If the sample is irregular and has no flat surface, a suitable method needs to be found to make the sample fully contact with MPPO. Divide the sample into appropriate parts and then cover it with MPPO. If necessary, the mass of MPPO can be appropriately increased to ensure that the sample is completely covered.

[0017] The beneficial effects of the present invention are as follows:

[0018] 1. Currently, there is no detection technology report on the migration amount of octyl glycidyl ether in modified polyphenylene ether (MPPO) at home and abroad. The method of the present invention makes up for the blank in the determination of the migration amount of the target substance in dry food simulants for food contact materials and articles.

[0019] 2. The present invention selects a supramolecular mixed solvent as an extractant and combines ultrasonic treatment to extract octyl glycidyl ether in modified polyphenylene ether, and after concentration and filtration, it is determined by GC-MS method. The results show that octyl glycidyl ether has good separation effect under the selected chromatographic conditions, has a good linear relationship in the concentration range of 0.020 - 0.20 mg / L, the detection limit is 0.01 mg / L, the quantification limit is 0.020 mg / L, the spiked recovery rate is between 98.5% and 101%, and the relative standard deviation is between 3.3% and 8.6%. This indicates that this method has good recovery rate and precision. The established gas chromatography-tandem mass spectrometry (GC-MS) not only has good separation effect, high sensitivity and good selectivity, but also has the advantages of rapidity and low detection limit, and has a very wide application prospect. Description of the Drawings

[0020] Figure 1 It is a result graph for optimizing the ultrasonic extraction time in the examples.

[0021] Figure 2 It is the total ion chromatogram of octyl glycidyl ether in dry food simulants in the examples. Detailed Embodiments

[0022] To facilitate the understanding of the present invention, the present invention will be described more comprehensively below. The present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the understanding of the disclosed content of the present invention more thorough and comprehensive.

[0023] To effectively investigate the safety and potential risks of the target substance in food contact materials and articles. Based on GC-MS technology, the migration amount of octyl glycidyl ether in modified polyphenylene ether (MPPO) was studied, and an accurate and efficient qualitative and quantitative detection technology was established to achieve the rapid identification and accurate determination of this substance.

[0024] Examples

[0025] 1 Reagents and Materials

[0026] 1.1 Reagents

[0027] Methanol, ethanol, acetonitrile, long-chain alkyl alcohols (n-pentanol, n-hexanol, n-heptanol, n-octanol, n-nonanol, n-decanol), tetrahydrofuran, n-hexane, all are chromatographically pure.

[0028] 1.2 Standards

[0029] Octyl glycidyl ether, with a purity of ≥98%, or a reference material certified by the state and granted a reference material certificate.

[0030] 1.3 Preparation of Standard Solutions

[0031] 1.3.1 Octyl glycidyl ether standard stock solution (1000 mg / L): Accurately weigh 10 mg (accurate to 0.1 mg) of octyl glycidyl ether standard into a 10 mL brown volumetric flask, make up to the mark with n - hexane, store in a dark and airtight condition in a refrigerator at 4 °C, and the storage period is 6 months.

[0032] 1.3.2 Octyl glycidyl ether standard intermediate solution (10 mg / L): Accurately pipette 0.1 mL of the octyl glycidyl ether standard stock solution (1.3.1) into a 10 mL brown volumetric flask, make up to the mark with methanol, store in a dark and airtight condition in a refrigerator at 4 °C, and the storage period is 3 months.

[0033] 1.3.3 Preparation of standard working solutions: Before use, serially dilute the standard intermediate solution with acetonitrile to prepare standard working solutions with concentrations of 0.020 mg / L, 0.040 mg / L, 0.080 mg / L, 0.10 mg / L, and 0.20 mg / L.

[0034] 2 Sample pretreatment

[0035] 2.1 Sample pre - treatment

[0036] The test specimens should be kept clean and avoid direct contact with hands. Before preparing the specimens, gently wipe them with non - woven fabric to remove the impurities adhering to the specimen surface. Do not wash the specimens with water or solvents.

[0037] 2.2 Preparation of test specimen solutions

[0038] In this example, select solid food packaging bags as specimens. Place the specimens on a glass plate, cover them with the outer cover of a petri dish, cut along the edge of the outer cover with a paper cutter. At the same time, prepare 3 specimens and place them flat inside the inner covers of 3 petri dishes respectively, and calculate the specimen surface area based on the area of the inner cover. Cover the surface of the specimens evenly with MPPO in an amount of 4 g / dm 2 and cover them completely with the inner cover without spilling outside; place them steadily in an oven at 100 °C for 1 h for migration experiments. After the migration experiment, take out the samples and place them in a desiccator. After cooling to room temperature, transfer the MPPO covering the surface of the solid food packaging bags to a stoppered triangular flask, add a supramolecular mixed solvent as the extraction solvent for ultrasonic extraction. After filtering through a slow quantitative filter paper with a diameter of 7 cm, extract with n - hexane, and concentrate the upper layer solution to 1 mL by nitrogen blowing and then measure on a machine.

[0039] 3 Preparation of blank specimens

[0040] Prepare method blank specimens according to the above operation process.

[0041] 4. Selection of test conditions

[0042] 4.1 Selection of extraction solvent

[0043] Select 1 g of the solid food simulant MPPO sample obtained after the migration experiment, add different extraction solvents, and ultrasonicate for 30 min. Select the best extraction solvent according to the recovery rate results. The extraction solvents include common organic solvents (methanol, ethanol, acetonitrile, and n - hexane), and supramolecular mixed solvents.

[0044] 4.1.1 Common organic solvents

[0045] Table 1 Results of the optimization experiment of the recovery rate of common organic solvents

[0046] Serial number Solvent type Solvent dosage (mL) Recovery rate / % 1 Methanol 5 49 2 Ethanol 5 43 3 Acetonitrile 5 65 4 n-Hexane 5 33 5 Acetonitrile 4 67 6 Acetonitrile 6 74 7 Acetonitrile 8 75 8 Acetonitrile 10 74

[0047] As can be seen from Table 1, among the common organic solvents, when acetonitrile is selected as the extraction solvent, the recovery rate is the highest. The amount of solvent has a certain influence on the recovery rate. When the amount of acetonitrile is 8 mL, the recovery rate reaches 75%.

[0048] 4.1.2 Supramolecular mixed solvents

[0049] The supramolecular mixed solvent is composed of supramolecular solvent 1, long - chain alkyl alcohol (selected from one of n - pentanol, n - hexanol, n - heptanol, n - octanol, n - nonanol, and n - decanol), tetrahydrofuran, and pure water. The specific preparation steps are as follows:

[0050] 1) Preparation of supramolecular solvent 1: Measure 1.5 mL of long - chain alkyl alcohol (selected from one of n - pentanol, n - hexanol, n - heptanol, n - octanol, n - nonanol, and n - decanol) and 8 mL of tetrahydrofuran, quickly inject them into a 50 - mL glass centrifuge tube, add 30.5 mL of ultrapure water, stir magnetically for 5 min, then centrifuge at 3000 r / min for 10 min. Use a syringe to transfer the upper organic phase into a glass bottle and store it sealed at 4 °C for later use as supramolecular solvent 1;

[0051] 2) Mix the supramolecular solvent 1 in step 1) with long - chain alkyl alcohol (the same substance as the long - chain alkyl alcohol that composes supramolecular solvent 1 in step 1), tetrahydrofuran, and pure water to obtain a supramolecular mixed solvent.

[0052] 4.1.2.1 Optimization of the type of long - chain alkyl alcohol

[0053] Using different types of long - chain alkyl alcohols (n - pentanol, n - hexanol, n - heptanol, n - octanol, n - nonanol, or n - decanol) as raw materials, prepare supramolecular solvent 1 according to the above step 1); then select 100 μL of the prepared supramolecular solvent 1, 2 mL of long - chain alkyl alcohol (the same substance as the long - chain alkyl alcohol that composes supramolecular solvent 1), 3 mL of tetrahydrofuran, and 30 mL of pure water, mix them to prepare a supramolecular mixed solvent, add 1 g of MPPO sample, and screen out the best long - chain alkyl alcohol according to the recovery rate results. The results are shown in Table 2 below.

[0054] Table 2 Optimization Experiment Results of Long-chain Alkyl Alcohols

[0055]

[0056] As can be seen from Table 2, when n-nonyl alcohol is selected to prepare supramolecular solvent 1, the recovery rate is the highest.

[0057] 4.1.2.2 Optimization of n-Nonyl Alcohol Dosage

[0058] Using n-nonyl alcohol as the raw material, supramolecular solvent 1 was prepared according to the above steps. Then, 100 μL of the prepared supramolecular solvent 1, n-nonyl alcohol (1.5, 2.0, 2.5 mL), 3 mL of tetrahydrofuran, and the remaining pure water were selected, and the total volume was controlled to be 35.1 mL. After mixing, a supramolecular mixed solvent was obtained. 1 g of MPPO sample was added, and the dosage of n-nonyl alcohol was optimized according to the recovery rate results. The results are shown in Table 3 below.

[0059] Table 3 Optimization Experiment Results of n-Nonyl Alcohol Dosage

[0060]

[0061] As can be seen from Table 3, when the dosage of n-nonyl alcohol is 2 mL, the recovery rate of the supramolecular mixed solvent is the highest.

[0062] 4.1.2.3 Optimization of Tetrahydrofuran Dosage

[0063] Using n-nonyl alcohol as the raw material, supramolecular solvent 1 was prepared according to the above steps. Then, 100 μL of the prepared supramolecular solvent 1, 2 mL of n-nonyl alcohol, tetrahydrofuran (2.5, 3.0, 3.5, 4.0, 4.5 mL), and the remaining pure water were selected, and the total volume was controlled to be 35.1 mL. After mixing, a supramolecular mixed solvent was obtained. 1 g of MPPO sample was added, and the dosage of tetrahydrofuran was optimized according to the recovery rate results. The results are shown in Table 4 below.

[0064] Table 4 Optimization Experiment Results of Tetrahydrofuran Dosage

[0065]

[0066] As can be seen from Table 4, when the dosage of tetrahydrofuran is 3 mL, the recovery rate of the supramolecular mixed solvent is the highest.

[0067] 4.1.2.4 Optimization of Supramolecular Solvent Dosage

[0068] Using nonanol as the raw material, supramolecular solvent 1 was prepared according to the above steps. Then, the prepared supramolecular solvent 1 (80, 100, 120, 150 μL), 2 mL of nonanol, 3 mL of tetrahydrofuran, and the remaining pure water were selected, and the total volume was controlled to be 35.1 mL. After mixing, a supramolecular mixed solvent was obtained. 1 g of MPPO sample was added, and the amount of supramolecular solvent 1 was optimized according to the recovery results. The results are shown in Table 5 below.

[0069] Table 5 Optimization experimental results of the amount of supramolecular solvent 1

[0070]

[0071] According to the screening results in Tables 1 - 5, the following supramolecular mixed solvent was selected as the best extraction solvent for octyl glycidyl ether in the MPPO sample: nonanol dosage: 2.0 mL, tetrahydrofuran dosage: 3.0 mL, 30.0 mL of ultrapure water, and the dosage of supramolecular solvent 1 (prepared from nonanol as the raw material): 100 μL.

[0072] 4.2 Selection of extraction time

[0073] After determining the supramolecular mixed solvent (2.0 mL of nonanol, 3.0 mL of tetrahydrofuran, 30.0 mL of ultrapure water, and 100 μL of supramolecular solvent 1) as the extraction solvent, the ultrasonic extraction time was optimized. The extraction effects at 5 min, 10 min, 15 min, 20 min, and 25 min were investigated respectively, and it was found that with the increase of the ultrasonic extraction time, the extraction effect changed little (as Figure 1 shown), but considering the response of the target substance and the efficiency of pretreatment comprehensively, and on the premise of meeting the detection requirements, the ultrasonic extraction time of 15 min was finally selected as the best extraction time.

[0074] 4.3 Optimization of inlet temperature

[0075] The boiling point of octyl glycidyl ether is 89.5 - 90.5 °C. The effects of 6 different inlet temperatures of 80 °C, 90 °C, 100 °C, 120 °C, 150 °C, and 200 °C on the peak area response of the target substance were investigated respectively. The optimization results of the inlet temperature are as follows: the peak area of the target substance increases with the increase of the inlet temperature. When the inlet temperature reaches 150 °C, the response reaches the maximum value. After that, the peak area response increases little with the increase of the inlet temperature. Considering comprehensive factors such as instrument energy consumption, the inlet temperature was finally set at 150 °C.

[0076] 4.4 Selection of injection mode

[0077] The peak emergence and response of chromatographic peaks were investigated under the same concentration with splitless injection and split injection (split ratios of 1:1, 2:1, 3:1, 5:1, and 10:1). After on-machine determination, it was found that when the split ratio was 3:1, the peak shape of octyl glycidyl ether chromatographic peak was the best. Therefore, the injection mode was selected as the split mode (split ratio of 3:1), and the injection volume was 2 μL.

[0078] 4.5 Selection of chromatographic column

[0079] For the selection of the chromatographic column, since only one substance needs to be detected, the peak shape of the chromatographic peak and the interference of the sample matrix on the chromatographic peak are mainly considered. Therefore, polar, non-polar, medium-polar, and strongly polar chromatographic columns can all be used. The commonly used weakly polar DB-5MS, medium-polar DB-624, and strongly polar HP-INNOWax capillary chromatographic columns in the laboratory were optimized. The results showed that the DB-624 (30 m × 0.25 mm × 1.4 μm) chromatographic column had less matrix interference and a good peak shape.

[0080] 4.6 Selection of chromatographic column flow rate

[0081] After setting the chromatographic column (DB-624 capillary chromatographic column) and column temperature, while keeping other experimental conditions fixed, the carrier gas flow rate was changed successively (0.5 mL / min, 1.0 mL / min, 1.5 mL / min, and 2.0 mL / min). It was found that when the chromatographic column flow rate was low, the peak emergence time was late; when the chromatographic column flow rate was high, the peak emergence time was too early. Either too high or too low chromatographic column flow rate would affect the column efficiency. A column flow rate of 1.5 mL / min was selected as the best.

[0082] 5. Instrument conditions

[0083] The optimized gas chromatography - mass spectrometry / mass spectrometry conditions are as follows: a) Chromatographic column: DB-624 chromatographic column (6% cyanopropyl / phenyl 94% dimethyl polysiloxane capillary chromatographic column), 30 m × 0.25 mm × 1.4 μm, or equivalent chromatographic column; b) Temperature programming: Hold at 50 °C for 0 min, rise to 100 °C at 3 °C / min, and hold for 2 min; then rise to 250 °C at 25 °C / min and hold for 1 min. c) Injector temperature: 150 °C; d) Column flow rate: 1.5 mL / min; e) Injection volume: 2 μL; f) Injection mode: Split injection, split ratio of 3:1. g) Ion source: Electron impact ionization source (EI); h) Ion source temperature: 230 °C; i) Quadrupole mass analyzer temperature: 150 °C; j) Transfer line temperature: 280 °C; k) Ionization energy: 70 eV; l) Solvent delay: 5.0 min; m) Detection mode: SIM (selected ion monitoring mode), qualitative and quantitative ions are shown in Table 6:

[0084] Table 6 Qualitative and Quantitative Ions of Octyl Glycidyl Ether

[0085] Serial number Compound Quantitative ion (m / z) Qualitative ion (m / z) 1 Octyl glycidyl ether 57 70、112

[0086] 6 Qualitative Determination

[0087] Under the optimized instrument conditions mentioned above, the sample solution and the standard working solution were determined separately. When the retention time deviation of the corresponding chromatographic peaks in the sample solution and the standard solution was within the range of ±0.5%, and in the mass spectrum of the sample solution after background subtraction, the selected ions all appeared, the signal-to-noise ratio was not less than 3, and the abundance of the qualitative ions met the requirements, it could be judged that the corresponding target analyte existed in the sample solution.

[0088] 7 Quantitative Determination

[0089] According to the instrument reference conditions listed above, the sample solution and the blank sample solution were separately injected into the gas chromatography - mass spectrometer to obtain the chromatographic peak areas of each target analyte, and the concentrations of octyl glycidyl ether in the sample solution and the blank sample solution were calculated according to the standard working curve.

[0090] 8 Linear Relationship of Standard Working Curve, Detection Limit, Quantitation Limit and Recovery Rate

[0091] Under the optimized determination conditions, the standard working solution (0.020 mg / L - 0.20 mg / L) was detected. Taking the concentration of octyl glycidyl ether in modified polyphenylene oxide (MPPO) as the abscissa, with the unit of mg / L, and the average peak area as the ordinate, the standard working curve was plotted to obtain the linear equation and the correlation coefficient. The test results showed that there was a good linear relationship between its concentration and the response value. The linear relationship of octyl glycidyl ether was higher than 0.997, and its detection limit was 0.01 mg / L, and the quantitation limit was 0.020 mg / L, which could well meet the needs of the test work.

[0092] Table 7 Linear Relationship Table of 0.020 mg / L - 0.20 mg / L

[0093]

[0094] The blank samples without octyl glycidyl ether in the background were pretreated separately, and three concentration levels of the target analyte with concentrations of 0.020 mg / L, 0.10 mg / L, and 0.20 mg / L were prepared for determination. Each level was determined separately 6 times for the recovery rate and precision tests. From the test results, it could be seen that the spiked recovery rates of the migration amount of octyl glycidyl ether in modified polyphenylene oxide (MPPO) determined by this method were between 98.5% and 101%, and the relative standard deviations were all between 3.3% and 8.6%, indicating that this method had good recovery rates and precision.

[0095] Table 8 Recovery Rate and Precision

[0096]

[0097] The above has described the embodiments of the present invention in detail. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those of ordinary skill in the art, various changes can be made without departing from the gist of the present invention. In addition, without conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

Claims

1. A method for determining the migration amount of octyl glycidyl ether in food contact materials using a solid food simulant, characterized in that, It includes the following steps: Select modified polyphenylene ether as a solid food simulant, conduct a migration experiment with the food contact material, add a supramolecular mixed solvent to the modified polyphenylene ether after the migration experiment, and perform ultrasonic-assisted extraction of the target substance. After filtration through quantitative filter paper, extract with n-hexane, take the upper layer solution and concentrate it by nitrogen blowing to obtain a test sample solution; respectively aspirate the test sample solution and the standard working solution for GC-MS detection, and use the external standard working curve method to determine the migration amount of octyl glycidyl ether; The conditions for the GC-MS detection are as follows: a) Chromatographic column: 6% cyanopropyl / phenyl 94% dimethyl polysiloxane capillary chromatographic column; b) Temperature programming: Hold at 50 °C for 0 min, rise to 100 °C at 3 °C / min, and hold for 2 min; rise to 250 °C at 25 °C / min and hold for 1 min; c) Injection port temperature: 150 °C; d) Column flow rate: 1.5 mL / min; e) Injection volume: 2 μL; f) Injection mode: Split injection, split ratio 3:1; g) Ion source: Electron impact ion source; h) Ion source temperature: 230 °C; i) Quadrupole mass analyzer temperature: 150 °C; j) Transfer line temperature: 280 °C; k) Ionization energy: 70 eV; l) Solvent delay: 5.0 min; m) Detection mode: Selected ion monitoring mode; The supramolecular mixed solvent, calculated by 100% of the total volume, includes the following components: long-chain alkyl alcohol 4.28 - 7.13%, tetrahydrofuran 7.18 - 12.88%, and the balance is water; the long-chain alkyl alcohol is selected from one of n-pentanol, n-hexanol, n-heptanol, n-octanol, n-nonanol, and n-decanol.

2. The method according to claim 1, characterized in that, The long-chain alkyl alcohol is selected from n-nonanol.

3. The method according to claim 2, wherein The supramolecular mixed solvent, calculated by 100% of the total volume, includes the following components: n-nonanol 5.71%, tetrahydrofuran 8.60%, and the balance is water.

4. The method according to claim 1, characterized in that, The specification of the chromatographic column is 30 m × 0.25 mm × 1.4 μm.

5. The method according to claim 1, characterized in that, In the selected ion monitoring mode, the qualitative ions m / z: 70, 112, and the quantitative ion m / z:

57.

6. The method according to claim 1, characterized in that, The preparation steps of the standard working solution are as follows: Weigh the octyl glycidyl ether standard product and prepare a standard stock solution of 1000 mg / L with n-hexane, then dilute it with methanol to a standard intermediate solution of 10 mg / L, and finally gradually dilute the standard intermediate solution with acetonitrile to prepare standard working solutions with concentrations of 0.020 mg / L, 0.040 mg / L, 0.080 mg / L, 0.10 mg / L, and 0.20 mg / L.

7. The method according to claim 1, wherein The time of ultrasonic treatment is 15 min.

8. The method according to claim 1, wherein The migration experiment is to evenly cover the food contact material with the modified polyphenylene ether in an amount of 4 g / dm 2 , and place it in an oven for the migration of the target substance.

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