Determination of lasalocid sodium in poultry feeds and premixes

Abstract

A method is given for the determination of lasalocid sodium in poultry feeds and premixes. The lasalocid is extracted from the feed material into methanol which has been acidified with hydrochloric acid, by agitation in an ultrasonic bath at 40 °C. The solution is allowed to stand until the suspended material settles out and a portion is filtered through a 0.45 µm filter. Lasalocid is then determined in the filtrate by reversed-phase HPLC on a C₁₈ octadecylsilane column using a mixture of methanol and a phosphate buffer as mobile phase.