Determination of 6 penicillin residues in honey. Scope and principle of liquid chromatography-tandem mass spectrometry

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1 Scope of application

It is suitable for the liquid chromatography-tandem mass spectrometry determination of penicillin G, penicillin V, naphthalene penicillin, oxacillin, o-cloxacillin, and dicloxacillin residues in honey
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2 Principle of the method

Penicillin G, penicillin V, naphthalene penicillin , oxacillin , o- cloxacillin , dicloxacillin residues in honey, after dissolving in deionized water, the solution is purified with OasisHLB or equivalent solid phase extraction column, liquid chromatography-tandem Measured by mass spectrometer and quantified by external standard method
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3 Reagents and materials

Methanol , acetonitrile : chromatographically pure; acetic acid: excellent grade; acetonitrile + water (1+3, v/v): measure 25 mL of acetonitrile and mix with 75 mL of water
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OasisHLB solid phase extraction column or equivalent: 500mg, 6mL
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Standard material: purity ≥9%
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Standard stock solution: accurately weigh an appropriate amount of each standard substance and prepare a standard stock solution with a concentration of 1.
0 mg/mL with acetonitrile
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Standard working solution: Draw an appropriate amount of standard stock solution as needed, and dilute it with a blank sample extract to form a matrix mixed standard working solution of appropriate concentration
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4 Instruments and equipment

Liquid chromatography-tandem quadrupole mass spectrometer: equipped with electrospray ionization source (ESI): analytical balance: each with a sensitivity of 0.
1mg and 0.
01g; liquid mixer; solid phase extraction vacuum device; liquid reservoir: 50mL; Micro syringe: 25μL, 100μL; scale sample tube: 5mL, with an accuracy of 0.
1mL; vacuum pump: the vacuum degree should reach 80kPa; pH meter: measurement accuracy of ±0.
02; nitrogen drying instrument
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5 Sample pretreatment

(1) Sample preparation

For laboratory samples without crystals, stir them evenly
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(2) Preparation of sample solution

Weigh 5g of sample (accurate to 0.
01g) into a 150mL Erlenmeyer flask, add 25mL of deionized water, and mix quickly on a liquid mixer for 1 minute to completely dissolve the sample
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