GB 5009.22-2026 National Food Safety Standard -Determination of B-group and G-group Aflatoxins in foods
1 Scope
This standard specifies the determination methods of aflatoxin B1, aflatoxin B2, aflatoxin G1 and aflatoxin G2 (hereinafter referred to as AFT B1, AFT B2, AFT G1 and AFT G2) in foods.
Method I - Liquid chromatography with post‑column derivatisation and Method III - Liquid chromatography‑tandem mass spectrometry of this standard are applicable to the determination of AFB1, AFB2, AFG1 and AFG2 in food.
Method II - Liquid chromatography with pre‑column derivatisation of this standard is applicable to the determination of AFB1, AFB2, AFG1 and AFG2 in oils and their products.
Method IV - Enzyme‑linked immunosorbent assay of this standard is applicable to the screening determination of AFB1 in cereals and their products, pulses and their products, nuts and seeds, oils and fats and their products, condiments, infant formula foods and infant complementary foods.
Method I - Liquid chromatography with post‑column derivatisation
2 Principle
The sample is extracted with an acetonitrile‑water solution, purified using an immunoaffinity column, detected by a liquid chromatograph with fluorescence detector, and quantified by the external standard method.
3 Reagents and materials
Unless otherwise specified, analytically-pure reagents and Class-I water as specified in GB/T 6682 are adopted for the purpose of this method.
3.1 Reagents
3.1.1 Acetonitrile (C2H3N).
3.1.2 Sodium chloride (NaCl).
3.1.3 Disodium hydrogen phosphate (Na2HPO4) (or sodium acid phosphate dodecahydrate, Na2 HPO4·12H2O).
3.1.4 Potassium dihydrogen phosphate (KH2PO4).
3.1.5 Potassium chloride (KCl).
3.1.6 Hydrochloric acid (HCl).
3.1.7 Tween-20 (C58H114O26).
3.1.8 Methanol (CH3OH): Chromatographically pure.
3.1.9 Glycerol(C3H8O3).
3.1.10 Acetonitrile (CH3CN): Chromatographically pure.
3.1.11 Iodine derivatisation reagent: iodine (I₂).
3.1.12 Bromine derivatisation reagent: pyridinium tribromide (C₅H₆Br₃N₂).
3.1.13 Electrochemical derivatisation reagents: potassium bromide (KBr), concentrated nitric acid (HNO₃).
3.2 Preparation of reagents
3.2.1 Acetonitrile-water solution (84+16): take 84mL acetonitrile, add 16mL water and mix uniformly.
3.2.2 Acetonitrile-water solution (70+30): take 70mL acetonitrile, add 30mL water and mix uniformly.
3.2.3 Phosphate buffer solution: weigh 8.00g sodium chloride, 1.20g disodium hydrogen phosphate (or 3.02g sodium acid phosphate dodecahydrate), 0.20g potassium dihydrogen phosphate and 0.20g potassium chloride, dissolve with 900mL water, test the pH of the solution, and if necessary, adjust the pH with 1 mol/L hydrochloric acid solution to match the immunoaffinity column. Dilute with water to 1 000 mL and mix well.
3.2.4 1 mol/L hydrochloric acid solution: take 8.6 mL of hydrochloric acid, add it to 80 mL of water, and after cooling, scale the volume to 100 mL.
3.2.5 1 % Tween‑20‑phosphate buffer solution (hereinafter referred to as PBST): take 10 mL of Tween‑20, dilute to 1 000 mL with phosphate buffer solution, and mix well.
3.2.6 10 % glycerol‑methanol solution: take 1 mL of glycerol, dilute to 10 mL with methanol, and mix well.
3.2.7 Acetonitrile‑methanol solution: take 50 mL of chromatographic‑grade acetonitrile, add it to 50 mL of chromatographic‑grade methanol, and mix well.
3.2.8 0.5 g/L iodine solution: weigh 0.1 g of iodine, dissolve it in 20 mL of chromatographic‑grade methanol, dilute to 200 mL with water, mix well, and filter through a 0.45 μm aqueous‑phase filter membrane. Prepare immediately before use (for use in the post‑column iodine derivatisation method only).
3.2.9 5 mg/L pyridinium tribromide solution: weigh 5 mg of pyridinium tribromide, dissolve it in 1 L of water, mix well, and filter through a 0.45 μm aqueous‑phase filter membrane. Prepare immediately before use (for use in the post‑column bromine derivatisation method only).
3.3 Standard products
3.3.1 AFT B1 standard product (C17H12O6, CAS:1162-65-8): standard product with purity ≥98% or its solution.
3.3.2 AFT B2 standard product (C17H14O6, CAS:7220-81-7): standard product with purity ≥98% or its solution.
3.3.3 AFG1 standard product (C17H12O7, CAS:1165-39-5): standard product with purity ≥98% or its solution.
3.3.4 AFG2 standard product (C17 H14O7, CAS:7241-98-7): standard product with purity ≥98% or its solution.
3.4 Preparation of standard solutions
Contents
Foreword I
1 Scope
2 Principle
3 Reagents and materials
4 Apparatus and equipment
5 Analysis steps
6 Expression of analysis results
7 Precision
8 Others
9 Principle
10 Reagents and materials
11 Apparatus and equipment
12 Analytical procedure
13 Expression of analysis results
14 Precision
15 Others
16 Principle
17 Reagents and materials
18 Apparatus and equipment
19 Analytical procedure
20 Expression of analysis results
21 Precision
22 Others
23 Principle
24 Reagents and materials
25 Apparatus and equipment
27 Expression of analysis results
28 Precision
29 Others
Annex A Method for calibrating the standard concentrations of AFB1, AFB2, AFG1 and AFG2
Annex B Liquid chromatograms
Annex C Reference mass spectrometry conditions for liquid chromatography‑tandem mass spectrometry
Annex D Liquid chromatography‑tandem mass spectrometry spectra
Annex E Method for the quality acceptance of enzyme‑linked immunosorbent assay kits
_________________
Standard
GB 5009.22-2026 National food safety standard - Determination of aflatoxins B and G in food (English)
Standard No.
GB 5009.22-2026
Status
to be valid
Language
English
File Format
PDF
Word Count
12500 words
Translation Price(USD)
250.0
Implemented on
2027-2-18
Delivery
via email in 1 business day
Detail of GB 5009.22-2026
Standard No.
GB 5009.22-2026
English Name
National food safety standard - Determination of aflatoxins B and G in food
Chinese Name
食品安全国家标准 食品中黄曲霉毒素B族和G族的测定
Chinese Classification
Professional Classification
GB
ICS Classification
Issued by
National Health Commission and State Administration for Market Regulation
GB 5009.22-2026 National Food Safety Standard -Determination of B-group and G-group Aflatoxins in foods
1 Scope
This standard specifies the determination methods of aflatoxin B1, aflatoxin B2, aflatoxin G1 and aflatoxin G2 (hereinafter referred to as AFT B1, AFT B2, AFT G1 and AFT G2) in foods.
Method I - Liquid chromatography with post‑column derivatisation and Method III - Liquid chromatography‑tandem mass spectrometry of this standard are applicable to the determination of AFB1, AFB2, AFG1 and AFG2 in food.
Method II - Liquid chromatography with pre‑column derivatisation of this standard is applicable to the determination of AFB1, AFB2, AFG1 and AFG2 in oils and their products.
Method IV - Enzyme‑linked immunosorbent assay of this standard is applicable to the screening determination of AFB1 in cereals and their products, pulses and their products, nuts and seeds, oils and fats and their products, condiments, infant formula foods and infant complementary foods.
Method I - Liquid chromatography with post‑column derivatisation
2 Principle
The sample is extracted with an acetonitrile‑water solution, purified using an immunoaffinity column, detected by a liquid chromatograph with fluorescence detector, and quantified by the external standard method.
3 Reagents and materials
Unless otherwise specified, analytically-pure reagents and Class-I water as specified in GB/T 6682 are adopted for the purpose of this method.
3.1 Reagents
3.1.1 Acetonitrile (C2H3N).
3.1.2 Sodium chloride (NaCl).
3.1.3 Disodium hydrogen phosphate (Na2HPO4) (or sodium acid phosphate dodecahydrate, Na2 HPO4·12H2O).
3.1.4 Potassium dihydrogen phosphate (KH2PO4).
3.1.5 Potassium chloride (KCl).
3.1.6 Hydrochloric acid (HCl).
3.1.7 Tween-20 (C58H114O26).
3.1.8 Methanol (CH3OH): Chromatographically pure.
3.1.9 Glycerol(C3H8O3).
3.1.10 Acetonitrile (CH3CN): Chromatographically pure.
3.1.11 Iodine derivatisation reagent: iodine (I₂).
3.1.12 Bromine derivatisation reagent: pyridinium tribromide (C₅H₆Br₃N₂).
3.1.13 Electrochemical derivatisation reagents: potassium bromide (KBr), concentrated nitric acid (HNO₃).
3.2 Preparation of reagents
3.2.1 Acetonitrile-water solution (84+16): take 84mL acetonitrile, add 16mL water and mix uniformly.
3.2.2 Acetonitrile-water solution (70+30): take 70mL acetonitrile, add 30mL water and mix uniformly.
3.2.3 Phosphate buffer solution: weigh 8.00g sodium chloride, 1.20g disodium hydrogen phosphate (or 3.02g sodium acid phosphate dodecahydrate), 0.20g potassium dihydrogen phosphate and 0.20g potassium chloride, dissolve with 900mL water, test the pH of the solution, and if necessary, adjust the pH with 1 mol/L hydrochloric acid solution to match the immunoaffinity column. Dilute with water to 1 000 mL and mix well.
3.2.4 1 mol/L hydrochloric acid solution: take 8.6 mL of hydrochloric acid, add it to 80 mL of water, and after cooling, scale the volume to 100 mL.
3.2.5 1 % Tween‑20‑phosphate buffer solution (hereinafter referred to as PBST): take 10 mL of Tween‑20, dilute to 1 000 mL with phosphate buffer solution, and mix well.
3.2.6 10 % glycerol‑methanol solution: take 1 mL of glycerol, dilute to 10 mL with methanol, and mix well.
3.2.7 Acetonitrile‑methanol solution: take 50 mL of chromatographic‑grade acetonitrile, add it to 50 mL of chromatographic‑grade methanol, and mix well.
3.2.8 0.5 g/L iodine solution: weigh 0.1 g of iodine, dissolve it in 20 mL of chromatographic‑grade methanol, dilute to 200 mL with water, mix well, and filter through a 0.45 μm aqueous‑phase filter membrane. Prepare immediately before use (for use in the post‑column iodine derivatisation method only).
3.2.9 5 mg/L pyridinium tribromide solution: weigh 5 mg of pyridinium tribromide, dissolve it in 1 L of water, mix well, and filter through a 0.45 μm aqueous‑phase filter membrane. Prepare immediately before use (for use in the post‑column bromine derivatisation method only).
3.3 Standard products
3.3.1 AFT B1 standard product (C17H12O6, CAS:1162-65-8): standard product with purity ≥98% or its solution.
3.3.2 AFT B2 standard product (C17H14O6, CAS:7220-81-7): standard product with purity ≥98% or its solution.
3.3.3 AFG1 standard product (C17H12O7, CAS:1165-39-5): standard product with purity ≥98% or its solution.
3.3.4 AFG2 standard product (C17 H14O7, CAS:7241-98-7): standard product with purity ≥98% or its solution.
3.4 Preparation of standard solutions
Contents of GB 5009.22-2026
Contents
Foreword I
1 Scope
2 Principle
3 Reagents and materials
4 Apparatus and equipment
5 Analysis steps
6 Expression of analysis results
7 Precision
8 Others
9 Principle
10 Reagents and materials
11 Apparatus and equipment
12 Analytical procedure
13 Expression of analysis results
14 Precision
15 Others
16 Principle
17 Reagents and materials
18 Apparatus and equipment
19 Analytical procedure
20 Expression of analysis results
21 Precision
22 Others
23 Principle
24 Reagents and materials
25 Apparatus and equipment
27 Expression of analysis results
28 Precision
29 Others
Annex A Method for calibrating the standard concentrations of AFB1, AFB2, AFG1 and AFG2
Annex B Liquid chromatograms
Annex C Reference mass spectrometry conditions for liquid chromatography‑tandem mass spectrometry
Annex D Liquid chromatography‑tandem mass spectrometry spectra
Annex E Method for the quality acceptance of enzyme‑linked immunosorbent assay kits
_________________
