SPE and MSPD as pre-separation techniques for HPLC of tetracyclines in meat, milk and cheese

Solid phase extraction (SPE) and Matrix solid phase dispersion (MSPD) have been tested as pre-separation procedures for high-performance liquid chromatography (HPLC) determination of tetracycline antibiotics in milk, meat and cheese. The extraction recoveries ranged from 48% to 86% for SPE and from 89% to 93% for MSPD at concentration levels of the maximal residual limits (MRL) recommended by the European Union to be 100 ng/g for the tetracyclines oxytetracycline (OTC), tetracycline (TC) and chlortetracycline (CTC). The detection limits were 15-22 ng/g for SPE and 30 ng/g for MSPD. Following the relatively simple SPE procedure we used a Lichrosorb RP-18 column and a diode array detector for HPLC. Results dealing with analysis of tetracyclines HPLC in cheese are published for the first time.