High Pressure Liquid Chromatographic Determination of Ethopabate in Feeds

Abstract

A high pressure liquid chromatographic (HPLC) method is described for determining ethopabate in poultry feeds. Feed samples containing ethopabate are finely ground, extracted 30 min by sonification with methanol-water (80+20), and filtered. The extract is cleaned up on an alumina column, and the first 4 ml eluate collected is analyzed. The drug is eluted through a μBondapak C18 column with acetonitrile-water (30+70) at a flow rate of 1.4 ml/min and detected by ultraviolet absorption at 280 nm. Chromatography is complete in 7 min, and detector response is linear. The drug is quantitated by peak height ratios. The procedure described is reproducible and shows good agreement with the official AOAC colorimetric method. The lower limit of detection is 2 ng by HPLC, making the method applicable to residue analyses.

Spectrofluorimetric analysis of ethopabate in veterinary formulations with application to residue determination in chicken muscles and liver

“…The results of the proposed method were favorably compared with those obtained using the reference method . Statistical analysis of the results obtained using the proposed and reference methods showed no significant difference in the performance of the two methods using Student's t ‐test and variance ratio F ‐test (Table ).…”

“…The reference method depends on the reversed phase liquid chromatographic determination of ETH in poultry feeds, with UV detection using a C 18 column and a mobile phase composed of acetonitrile/water (30: 70 v/v) at a flow rate of 1.4 mL/min. Detection was carried out at 280 nm using SPE for sample cleanup .…”