Excretion study of stanozolol in bovine by HPLC-tandem mass spectrometry

Stanozolol is an anabolic steroid illicitly used for growth promoting purposes in animal production. For reasons of public health the use of anabolic steroids as growth promoters is officially banned in Europe in animals intended for consumption. The aim of this work is the investigation of stanozolol metabolites, 3′-hydroxystanozolol, 4β- hydroxystanozolol and 16β- hydroxystanozolol in urine samples after stanozolol administration to a young calf. After solid phase extraction of urine samples, detection is carried out by HPLC-MS-MS multiple reaction monitoring. Average recovery for the three metabolites is 80%. The method is highly specific and has been validated in terms of linearity, inter and intra day precision. In addition the decision limit CCα and the detection capability CCβ have been determined.