GB 31604.64-2025National food safety standard - Food contact materials and products - Determination of migration of citrate and sebacate compounds (English PDF)

0.1 g) of olive oil into 6 glass test tubes. Accurately pipette 0 mL,

0.015 mL,

0.030 mL,

0.060 mL,

0.12 mL, and

0.15 mL of the mixed intermediate standard solution B; mix well; and then add

0.25 mL of 10% (mass fraction) ammonia water and

3.00 mL of acetonitrile; vortex for extraction for 5 min; allow to stand for separation; and transfer the supernatant acetonitrile solution to a clean volumetric flask. Add

3.00 mL of acetonitrile and repeat the extraction once more. Combine the two extracts into a 15 mL centrifuge tube containing 900 mg of magnesium sulfate, 150 mg of PSA, and 150 mg of C18; and centrifuge at 4000 r/min for 5 min. Take

4.00 mL of the supernatant acetonitrile solution; blow it to near dryness with nitrogen; and then make constant volume to

1.00 mL with acetonitrile to obtain mixed standard working solutions with mass concentrations of 0 mg/kg,

0.50 mg/kg,

5.0 mg/kg. Prepare immediately before use.

3.5.7 Standard working solutions for chemical alternative solvents (95% ethanol and isooctane) Respectively and accurately pipette 0 mL,

0.020 mL,

3.1 Reagents

3.1.1 N-hexane (C6H14). Chromatographic grade.

3.1.2 Acetonitrile (C2H3N). Chromatographic grade. 3.1.3 25% (mass fraction) ammonia water.

3.1.4 Magnesium sulfate (MgSO4).

3.1.5 Anhydrous ethanol (C2H6O). Chromatographic grade.

3.1.6 Glacial acetic acid (C2H4O2).

3.1.7 Isooctane (C8H18). Chromatographic grade.

3.1.8 Olive oil. It shall comply with the provisions of fat and oil food simulants in GB 5009.156.

3.2 Materials

3.2.1 Ethylenediamine-N-propylsilylane silica gel filler (PSA). 40 µm~60 µm.

3.2.2 Octadecylsilane chemically bonded silica gel filler (C18). 40 µm~60 µm.

3.3 Preparation of reagents

3.3.1 Acidic, ethanol-containing, and fat- and oil-containing food simulants and chemical substitute solvents. As specified in GB 31604.1 and GB 5009.156. 3.3.2 10% (mass fraction) ammonia water. Pipette 211 mL of 25% ammonia water and 289 mL of water; and mix well.

3.4 Reference standard

3.4.1 Triethyl citrate (C12H2O7, CAS No.. 77-93-0). Purity >=98%, or a reference standard certified by the state and granted a reference standard certificate.

3.4.2 Dibutyl sebacate (C18H34O4, CAS No.. 109-43-3). Purity >=98%, or a reference standard certified by the state and granted a reference standard certificate.

3.4.3 Acetyl tributyl citrate (C20H34O8, CAS No.. 77-90-7). Purity >=98%, or a reference standard certified by the state and granted a reference standard certificate.

3.4.4 Di(2-ethylhexyl) sebacate (C26H50O4, CAS No.. 122-62-3). Purity >= 98%, or a reference standard certified by the state and granted a reference standard certificate.

3.4.5 Diisooctyl sebacate (C26H50O4, CAS No.. 27214-90-0). Purity >= 98%, or a reference standard certified by the state and granted a reference standard certificate.

3.4.6 Bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate (C28H52N2O4, CAS No.. 52829-07-9). Purity >= 98%, or a reference standard certified by the state and granted a reference standard certificate.

3.5 Preparation of standard solutions

3.5.1 Preparation of dingle standard stock solutions (1000 mg/L) Respectively and accurately take 10 mg (accurate to

0.1 mg) of each of the following reference standards. triethyl citrate, dibutyl sebacate, acetyl tributyl citrate, di(2-ethylhexyl) sebacate, diisooctyl sebacate, and bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate. Dissolve each reference standard in n-hexane and then transfer to a 10 mL brown volumetric flask. Make constant volume to the mark with n-hexane and mix well. Transfer the solution to a brown glass bottle and store in a refrigerator at 0°C~4°C, protected from light. Shelf life is 6 months.

3.5.2 Preparation of mixed standard intermediate solution A (100 mg/L) Respectively and accurately pipette

1.00 mL of each of the above 6 single standard stock solutions into the same 10 mL brown volumetric flask. Accurately make constant volume to the mark with anhydrous ethanol and mix well. Transfer the solution to a brown glass bottle and store in a refrigerator at 0°C~4°C, protected from light. Shelf life is 3 months.

3.5.3 Preparation of mixed standard intermediate solution B (100 mg/L) Respectively and accurately pipette

1.00 mL of each of the above 6 single standard stock solutions into the same 10 mL brown volumetric flask. Accurately make constant volume to the mark with n-hexane and mix well. Transfer the solution to a brown glass bottle and store in a refrigerator at 0°C~4°C, protected from light. Shelf life is 3 months.

3.5.4 Standard working solution for acidic food simulants Respectively pipette

5.00 mL of 4% acetic acid into six graduated glass tubes. Accurately transfer 0 mL,

0.020 mL,

0.10 mL,

0.20 mL,

0.40 mL, and

0.50 mL of mixed standard intermediate solution A. Add 4% acetic acid and make constant volume to 10 mL; mix well. Accurately transfer

2.4 mL of 10% (mass fraction) ammonia water to each tube. Respectively add

5.00 mL of n-hexane to each tube. Vortex for extraction for 5 min. Centrifuge at 4000 r/min for 5 min. Transfer the supernatant n-hexane solution to a clean volumetric flask. Respectively add

5.00 mL of n-hexane to each flask and repeat the above steps. Combine the two solutions and make constant volume to 10 mL with n-hexane; and then obtain the mixed standard working solutions with mass concentrations of 0 mg/L,

0.20 mg/L,

5.0 mg/L. Prepare immediately before use.

3.5.5 Standard working solution for water- and ethanol-containing food simulants Respectively pipette

5.00 mL of food simulants into each of 6 graduated glass tubes. Accurately pipette 0 mL,

0.020 mL,

4.2 Electronic Balance. With sensitivity of 0.0001 g and

0.1 g, respectively.

4.3 Vortex Shaker.

4.4 Pipettes. Capacities of 200 µL,

4.5 Centrifuge. With maximum speed >= 4000 r/min.

4.6 Nitrogen evaporator.

5.1 Preparation of test solution

5.1.1 Migration test Food contact materials and products shall be subjected to migration tests in accordance with the provisions of GB 31604.1 and GB 5009.156.If the soaking solution obtained from the migration test cannot be tested immediately, it shall be stored in a refrigerator at 0°C ~ 4°C protected from light; and the shelf life shall not exceed 72 h. If further test is to be performed, the soaking solution shall be brought to room temperature before use.

5.1.2 Treatment of immersion solution of acidic food simulants Accurately pipette

10.00 mL of the immersion solution into a glass test tube; mix well; and then accurately pipette

2.4 mL of 10% (mass fraction) ammonia water. Add

5.00 mL of n-hexane; vortex for extraction for 5 min; centrifuge at 4000 r/min for 5 min; and transfer the supernatant n-hexane solution to a clean volumetric flask. Add another

5.00 mL of n-hexane and repeat the above steps. Combine the two solutions and make constant volume to 10 mL with n-hexane. Take the clear liquid for instrumental analysis.

5.1.3 Treatment of water and immersion solution of ethanol-containing food simulants Accurately pipette

10.00 mL of the immersion solution into a glass test tube; mix well; then accurately pipette

0.25 mL of 10% (mass fraction) ammonia water. Add

5.00 mL of n-hexane; vortex for extraction for 5 min; centrifuge at 4000 r/min for 5 min; transfer the supernatant n- hexane solution to a clean volumetric flask. Add another

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Notes and Explanations

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