GB/T 22989-2008 in English

《GB/T 22989-2008牛奶和奶粉中头孢匹林、头孢氨苄、头孢洛宁、头孢喹肟残留量的测定 液相色谱-串联质谱法》由469-nq（国家标准委农业食品部）归口，主管部门为国家标准化管理委员会。
本标准规定了牛奶和奶粉中头孢匹林、头孢氨苄、头孢洛宁、头孢喹肟残留量的液相色谱?串联质谱测定方法。
本标准适用于牛奶和奶粉中头孢匹林、头孢氨苄、头孢洛宁、头孢喹肟残留量的测定。

1 Scope

The standard specifies the determination of cefapirin, cephalexin, cefalonium, cefquinome residues in milk and milk powder—LC-MS-MS method.

The standard is applicable to the determination of cefapirin, cephalexin, cefalonium, cefquinome residues in milk and milk powder.

The method detection limit of milk of this standard: 4.0μg/kg for cefapirin, cephalexin, cefalonium and cefquinome; the method detection limit of milk powder of this standard: 32μg/kg for cefapirin, cephalexin, cefalonium, cefquinome.

2 Normative references

The following normative documents contain provisions which, through reference in this text, constitute provisions of this standard. For dated references, subsequent amendments (excluding corrections) to, or revisions, of any of these publications do not apply to this standard. However, parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition applies.

GB/T 6379.1 Accuracy (trueness and precision) of measurement methods and results—Part 1: General principles and definitions (GB/T 6379.1-2004, ISO 5725-1:1994, IDT)
GB/T 6379.2 Accuracy (trueness and precision) of measurement methods and results—Part 2: Basic method for the determination of repeatability and reproducibility of a standard measurement method (GB/T 6379.2-2004, ISO 5725-2:1994, IDT)
GB/T 6682 Water for analytical laboratory use—Specification and test methods (GB/T 6682-2008, ISO 3696:1987, MOD)


3 Principle

The residues of the four cephalosporins in the specimen are first extracted with acetonitrile and phosphate buffer solution and purified with a solid phase extraction column, and then determined by liquid chromatograph mass spectrometer, and quantified by external standard method.

Foreword i
1 Scope
2 Normative references
3 Principle
4 Reagents and materials
5 Apparatuses
6 Specimen preparation and preservation
7 Determination procedures
8 Result calculation
9 Precision
Annex A (Informative) Multi reaction monitoring (MRM) chromatograms of reference materials
Annex B (Informative) Recovery rate