SN/T 5222-2019 in English

Technical background and importance of the standard

With the widespread application of perfluoroalkyl compounds (PFASs) in industry, their residues in food have attracted increasing attention. SN/T 5222-2019 standard has established a systematic detection scheme for 20 PFASs for honey, a special matrix, filling the gap in the detection standard of persistent pollutants in my country's bee products.

Core Principle of the Method

Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) was used for detection. The key steps include:

Key Operation Points

1. Sample Pretreatment

After weighing 5g honey sample, special attention should be paid to:

• Use polypropylene centrifuge tube to avoid background contamination
• Add isotope internal standard (such as 13C4-PFOA) to correct matrix effect
• Nitrogen blowing temperature is strictly controlled below 40℃

2. Instrument Parameter Optimization

Mass spectrometer parameter setting points:

* indicates quantification ion

Method Validation Data

Standard Validation Results Show:

• Limit of Quantitation (LOQ): 0.3μg/kg (all compounds)
• Precision: RSD≤11.5% (3 addition levels)
• Linear Range: 0.2-10μg/L (R²＞0.995)

Implementation Suggestions

1. Key points of laboratory quality control

• Reagent blank and matrix blank should be performed for each batch of samples
• PEEK tubing is recommended to replace Teflon material
• Regularly verify the contamination of the ion source

2. Outlook for standard development

In the future, it can be expanded to:

• Detection of other bee products (royal jelly, pollen)
• Supplementary detection of new short-chain PFASs
• Application of automated pre-treatment equipment