HPLC determination of tetracyclines in lamb muscle using an RP-C18 monolithic type column

Four antibiotics, oxytetracycline (OTC), tetracycline (TCC), chlortetracycline (CTC) and doxycycline (DXC) were separated and quantified in lamb muscle extracts using a commercial RP-C-18 monolithic HPLC column and a DAD detector. Operating an isocratic flow of 2 mL min(-1) the HPLC separation of the four compounds was obtained within 6 min with a good peak symmetry and an acceptable separation factor (1.27) for the critical peak pair OTC-TCC. Values of the normalized numbers of theoretical plates (N cm(-1)) were comprised between 338-780 while the limits of quantitation (S/N = 10) were within 12-65 mug kg(-1).