GB/T 44740-2024 in English

1. Standard Overview

This standard (GB/T 44740-2024) specifies the liquid chromatography-tandem mass spectrometry method for the determination of chlorpheniramine and brompheniramine in feed, and is applicable to the detection of samples such as compound feed, concentrated feed, and concentrate supplements.

1.1 Scope of the Standard

1.2 Background of Standard Formulation

With the development of feed industry, the use of additives is becoming more and more common. As commonly used drug ingredients, the residues of chlorpheniramine and brompheniramine in feed have attracted much attention. In order to ensure the quality safety of animal products and human health, this standard is formulated to regulate the detection method.

2. Interpretation of the standard

2.1 Principle of the method

The analyte in the sample is extracted with formic acid-acetonitrile solution, purified by mixed strong cation exchange solid phase extraction cartridge, and determined by liquid chromatography-tandem mass spectrometry, calibrated by matrix matching standard curve, and quantified by external standard method.

2.2 Key technologies

• Liquid chromatography-tandem mass spectrometry (LCMS): used to separate and detect target compounds.
• Solid phase extraction cartridge: used for sample purification and removal of impurity interference.

3. Implementation Suggestions

3.1 Sample Processing Precautions

Ensure uniform crushing during sample preparation to avoid overly large particles affecting extraction efficiency. Blank samples should be of the same type and have no interference from the analyte.

3.2 Reagent and Instrument Management

• The purity and expiration date of reagents must be checked before use.
• The instrument should be calibrated regularly to ensure stable performance.

3.3 Data Analysis Suggestions

When processing data, pay attention to the linear relationship of the standard curve (correlation coefficient ≥0.99) and pay attention to the single-point calibration deviation range (≤30%).