Development of an HPLC assay to determine closantel in goat milk

IMPERIALE, F.; FARIAS, C.; IEZZI, S.; SALLOVITZ, J.; LANUSSE, C.

Rosario

Congreso; XLI Reunión anual de la Asociación Argentina de Farmacología Experimental; 2009

Sociedad Argentina de Farmacología Experimental

Closantel is an antiparasitic drug used to treat the liver fluke trematode (F. hepatica) and some nematode (Haemonchus contortus) infections in ruminant species. Development of an adequate analytical methodology is required to assessing closantel residues in milk obtained from treated animals intended for human consumption. A simple reversed-phase HPLC analytical method with fluorescence detection was developed, validated and applied to quantitatively determine closantel in goat milk. Linearity, precision, recovery and limit of quantification of the method were determined. Drug extraction from samples was effectively performed using a double liquid-liquid extraction and clean up by solid phase extraction. Regression analyses were linear over the concentration range examined (from 50 to 400 ng/ml) and correlation coefficient of the calibration line was 0.9981. The developed HPLC method allowed the quantification of closantel up to 50 ng/ml within internationally accepted coefficient of variations (<20%). The accuracy of the test procedures obtained showed a CV=4.2%, being considered analytically satisfactory. Recovery values were higher than 70%. The analytical method described here is a useful tool for detecting residues of this antiparasitic drug in goat milk.