Determination of vitamin K3 in feeds - High performance liquid chromatography
1 Scope
This standard specifies a high performance liquid chromatography for the determination of vitamin K3 (menadione sodium bisulfite, menadione nicotinamide bisulfite and menadione dimethylpyrimidinol bisulfite, calculated in menadione) in feeds.
This standard is applicable to the determination of vitamin K3 in formula feed, concentrate, additive premixed feed and concentrate supplement. The limit of quantification of the method is 0.4mg/kg.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 603 Chemical reagent - Preparations of reagent solutions for use in test methods
GB/T 6682 Water for analytical laboratory use - Specification and test methods
GB/T 14699.1 Feeding stuffs - Sampling
GB/T 20195 Animal feeding stuffs - Preparation of test samples
3 Principle
The test samples are extracted by trichloromethane and sodium carbonate solution and then transformed into free menadione, separated by reversed-phase C18 column, detected by UV detector, and quantified by external standard method.
4 Reagents and materials
Unless otherwise specified, all reagents in this standard are analytically-pure reagents, the test water shall meet the requirements Grade III water in GB/T 6682, the chromatography water shall meet the requirements Grade I water in GB/T 6682, and the solution is prepared in accordance with GB/T 603.
4.1 Trichloromethane.
4.2 Methanol: chromatographically pure.
4.3 Anhydrous sodium carbonate.
4.4 Sodium carbonate solution: c=1mol/L. Weigh 10.6g of anhydrous sodium carbonate, add 100mL of water to dissolve and shake well.
4.5 Anhydrous sodium sulfate.
4.6 Diatomite.
4.7 Mixture of diatomite and anhydrous sodium sulfate: weigh 3g of diatomite and 20g of anhydrous sodium sulfate and mix them well.
4.8 Menadione standard: with content≥96%.
Foreword i
1 Scope
2 Normative references
3 Principle
4 Reagents and materials
5 Apparatuses
6 Sampling and sample preparation
7 Analytical procedures
8 Result calculation
9 Repeatability
Annex A (Informative) Examples of labeled amount and weighing amount of feed samples and dilution factor of menadione extract
Annex B (Informative) Chromatogram of menadione standard solution