The Validation of a Method for the Determination of Chloramphenicol in Milk

The liquid chromatography tandem mass spectrometry (LC-MS/MS) method with the liquid-liquid extraction and SPE (Waters OASIS HLB column) cleaning process was validated for the determination of chloramphenicol (CAP) residues in milk. The optimisation of the mass spectrometry parameters was performed by injecting the CAP standard solutions into the electrospray ion (ESI) source. The mass spectrometer was operated in the negative ESI mode. The validation data fulfilled the requirements established in the Regulations Decisions 2020/657/EC. During the validation process the chloramphenicol-D5 as an internal standard was used. The obtained results indicated the good linearity (R2 > 0.99) within the range of 0.1–2.0 μg/kg. The mean recovery for spiking levels was 96.5 ±10.59%. The limit of quantification (LOQ) was 0.1 μg /kg. The repeatability was 10.6%. The method fulfilled all the 2020/657/EC guidelines and thus can be extended for the routine analysis of CAP residues in milk.