QuEChERS Method for Simultaneous Analysis of Tetracyclines from Chicken by HPLC–DAD

Tetracyclines (TCs) are among the most widely used antibiotics worldwide for treating bacterial infections (both Gram-positive and Gram-negative) in humans and animals. In Brazil, chicken is one of the most produced and traded meats, with TCs being the primary antibiotics used in its production. This study applied two experimental designs to optimize the QuEChERS method for simultaneous quantitative analysis by HPLC–DAD of three TCs (tetracycline, chlortetracycline, and oxytetracycline) in chicken. The optimized conditions of the QuEChERS method for the preconcentration of TCs were 500 mg of sample, 1000 mg of Na₂SO₄, 700 mg of NaCl, 100 mg C18, 100 mg of PSA in 10 mL of the extracting solvent, vortex for 1 min, and centrifugation 4000 rpm for 5 min with a total run time of 10 min. LOQ values were lower than the MRL for all antibiotics established by ANVISA, precision in intra-day and inter-day ranged from 0.1 to 5.0%, and recovery ranged from 80 to 101%, greatly improving the work efficiency. The analytical method was applied to four commercial chicken breast samples and other proteins, one for beef and one for pork, of which no residues were found. The “GREEnness” of the optimized method demonstrated that the proposed approach made it possible to develop a “greener” method than traditional methods.