An HPLC method to determine moxidectin residues in sheep milk and dairy products

IMPERIALE, F.; SALLOVITZ, J.; LIFSCHITZ, A.; VIRKEL, G.; LANUSSE, C.

Tandil

Congreso; XXXIV Reunión Anual de la Asociación Argentina de Farmacología Experimental; 2002

Asociación Argentina de Farmacología Experimental

Moxidectin (MXD) is a potent anthelmintic compound active against a wide variety of nematode and arthropod parasites. Parasistim causes important losses in sheep dairy farm and the extra-label use of endectocide compounds, including MXD, is widespread. An analytical procedure to optimize and validate a simple and rapid high performance liquid chromatographic (HPLC) method was developed to quantify MXD residue concentrations in milk and dairy products (cheese). Drug free samples (milk and cheese) were fortified with MXD in the concentration range between 0.1 and 100 ng.g-1. Abamectin (ABM) was used as internal standard. Liquid and solid-phase extraction procedures were used for sample preparation. Calibration lines for MXD in the range of 0.1 - 10 and 10 - 100 ng.g-1 were plotted using the peak area ratio between MXD and ABM (internal standard) vs. analyte concentrations. HPLC method allowed the quantification of MXD up to 0.1 ng.g-1 in sheep milk and cheese with acceptable coefficient of variation (lower than 15%). Recovery values between (0.1 - 50 ng.g-1) concentrations were higher than 70%. This HPLC method is reliable to determining the presence of residual concentrations of MXD in milk and cheese to assure consumer´s safety.