Scope of application and method principles for determination of streptomycin, dihydrostreptomycin and kanamycin residues in honey

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1 Scope of application

It is suitable for the determination of residues of streptomycin, dihydrostreptomycin and kanamycin in honey by liquid chromatography-tandem mass spectrometry
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2 Principle of the method

The antibiotics in the honey sample are extracted with phosphate buffer solution, and purified with Oasis HLB solid phase extraction column and carboxylic acid type solid phase extraction column or equivalent
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3 Reagents and materials

Methanol , acetonitrile : chromatographically pure
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0.
2mol/L phosphate buffer solution: pH=8.
0
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0.
01mol/L sodium heptane sulfonate solution: Weigh 2.
20 g sodium heptane sulfonate , dissolve in water, and dilute to 1L
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SPE elution solution: Take 4 mL of formic acid and dilute to 100 mL with 0.
01 mol/L heptane sulfonate solution
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20% methanol solution (1+3, v/v): Take 25 mL of methanol and dilute to 100 mL with water
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The purity of standard materials is ≥98%
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0mg/mL standard stock solution: Weigh appropriate amounts of streptomycin, dihydrostreptomycin and kanamycin standard substances, respectively dissolve them with 0.
3% acetic acid aqueous solution and prepare 1.
0mg/mL standard stock solutions
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1ug/mL mixed standard solution: draw appropriate amount of streptomycin, dihydrostreptomycin and kanamycin standard stock solution, dilute with 0.
3% acetic acid water

0.
1ug/mL mixed standard solution, protected from light, stored in a -18℃ freezer
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Oasis HLB solid phase extraction column (60mg, 3mL) or equivalent: pre-treat with 5mL methanol and 10mL water in sequence before use, and keep the cartridge moist
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Carboxylic acid type solid phase extraction column (500mg, 3mL) or equivalent: Pre-treat with 5mL methanol and 10mL water in sequence before use, and keep the cartridge moist
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Filter membrane: 0.
2um
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4 Apparatus and equipment

Liquid chromatography-tandem quadrupole mass spectrometer, equipped with electrospray ion source
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5 Sample pretreatment

(1) Sample preparation

The test samples are mixed evenly, and 0.
5kg is separated as the sample
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(2) Preparation of the sample solution to be tested

Weigh 10g of honey sample (accurate to 0.
01g), place it in a 200mL Erlenmeyer flask, add 20mL 0.
2mol/L phosphate buffer solution, vortex and mix for 5 minutes, then pour all into the stock solution connected to the Oasis HLB solid phase extraction column In the device, the Oasis HLB solid phase extraction column is connected to the carboxylic acid type solid phase extraction column with an adapter, and the sample liquid is passed through the OasisHLB solid phase extraction column and the carboxylic acid type solid phase extraction column at a flow rate of less than 2 mL/min on the solid phase extraction device.
After the sample solution passes through the two solid phase extraction columns, wash the two solid phase extraction columns with 10 mL of water and 10 mL of 20% methanol solution successively, discard all the effluent and the Oasis HLB solid phase extraction column
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(3) Preparation of matrix mixed standard calibration solution

Weigh 10g of five negative honey samples (accurate to 0.
01g), put them in a 200mL Erlenmeyer flask and add an appropriate amount of mixed standard solution to make streptomycin, dihydrostreptomycin and kanamycin, each containing 2.
5μgkg, 5.
0 ugkg, 10.
0ug/kg, 50.
0ug/kg and 100.
0ug/kg matrix standard solution
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The rest is completed according to the above steps
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