Determination of erythromycin and tylosin residues in honey by LC/MS/MS.

Antibiotics are used in apiculture to protect bees against a variety of brood diseases. As a result of the development of resistance to oxytetracycline, erythromycin and tylosin are increasingly used for the prevention and treatment of these diseases. Therefore, Brazilian authorities have added these antibiotics to the National Regulatory Monitoring Program for the control of residues in honey. An analytical method has been developed for the determination of residues of erythromycin and tylosin in honey. The procedure involves solid-phase extraction of diluted honey samples with Bond Elut cartridges, followed by LC/MS with electrospray positive ionization in the multiple reaction monitoring mode. Two characteristic transitions were monitored for both drugs. Average analyte recoveries of erythromycin and tylosin ranged from 99 to 109% from sets of replicate honey samples fortified with drug concentrations of 5, 10, 15, and 20 microg/kg. The method decision limits were determined to be 1.27 and 0.59 microg/kg for erythromycin and tylosin, respectively. The detection capabilities were 5 and 5.2 microg/kg for erythromycin and tylosin, respectively.