GB/T 35531-2017 in English

Reagents and Materials

• Acetone (chromatographic grade): used for sample extraction
• Acetophenone standard substance (CAS No. 98-86-2): purity ≥ 99%
• Sample bottle: PTFE/Silica bottle pad, good sealing

Instruments and Equipment

• Gas Chromatography-Mass Spectrometry (GC-MS): equipped with EI Source
• Ultrasonic generator: with temperature control function
• Analytical balance: accurate to 0.1 mg

Sample preparation and processing flow

1. Take a representative sample and make a small test piece ≤3 mm×3 mm×3 mm≥10 g
2. Weigh 1.0 g of sample and place it in a 40 mL reaction bottle
3. Add 10 mL of chromatographic grade acetone and shake to mix
4. Ultrasonic extraction for 60 min (50°C)
5. Filter and inject for analysis

Gas chromatography-mass spectrometry analysis conditions

• Chromatographic column: DB-5MS column (30 m × 0.25 mm × 0.25 μm)
• Temperature program: starting temperature 50°C, increase to 280°C at 20°C/min
• Ion source temperature: 230°C
• Ionization mode: EI, energy 70 eV
• Scan mode: Selected ion scanning (SIM), qualitative ion m/z: 51, 77, 105, 120

Result calculation and quality control

Acetophenone content calculation formula:

• X: Acetophenone content in sample (mg/kg)
• c: Standard working curve concentration (mg/L)
• V: Extraction solvent volume (mL)
• m: sample mass (g)

Laboratory conditions

• Equipped with GC-MS instruments and related accessories
• Establish a standard sample library and reagent management system
• Equipped with ultrasonic extraction device

Staff training

• Operators must undergo professional training
• Familiar with gas chromatography-mass spectrometry technology
• Have laboratory safety protection awareness

Data management

• Establish an electronic data management system
• Regularly calibrate standard curves and equipment
• Ensure data integrity and traceability