DETERMINATION OF AMOXICILLIN AND SULFADIMIDIN RESIDUES IN MILK WITH LIQUID CHROMATOGRAPHY TANDEM MASS SPECTROMETRY (LC-MS/MS) USING LIQUID-LIQUID EXTRACTION (LLE)

Gjylai Alija, Zehra Hajrullai-Musliu, Arlinda Hajxhiu-Zajmi, Dashnor Nebija

Abstract

Antibiotics and sulphonamides are widely used in animal production to prevent (prophylactic use) and treat (therapeutic use) diseases as well as to promote growth. However, all drugs that are administered to food-producing animals may lead to residues in the edible tissues, milk, or eggs. The presence of these residues may pose potential health risks, including allergic reactions, direct toxic effects, carcinogenic effects and a change in the resistance of bacteria exposed to antibiotics. Due to harmful effects of residues, legislation regarding the control and to monitor these residues in food of animal products are given in EU Council Regulation 37/2010/EU. The aim of this study is to optimize and validate the LC-MS / MS method for residues analysis of Amoxicillin and Sulfadimidin in milk using Liquid-Liquid Extraction. Milk samples, were collected during 2016. The extraction method was done according to the method of Liquid-Liquid Extraction. The optimization of chromatographic conditions and MS / MS detectors is achieved by a mix of standards. The chromatographic separation was achieved on a Kinetex® C18 column (1.7 µM 100 A, LC Column 50 x 2.1 mm) column followed by tandem mass spectrometry using an electro spray ionization source in positive mode. Validation of the method was performed according to Decision 2002/657/EC. Optimization and validation process was carried out according to Commission Decision 2002/657/EC criteria. In validation process, decision limit (CCa), detection capability (CCß), and linearity. The linear regression analysis showed good correlation with R2=0.994 and R2=0.996. The method of Liquid-Liquid Extraction was inappropriate because it was not possible to detected the residues of Amoxicillin. Method successful validation according to the European Union requirements and its application to samples demonstrated its efficiency for veterinary control of drugs in milk.

Pages: 43 - 49