This article describes the development of an LC-MS/MS method for the determination of 20-hydroxyecdysone and its metabolites in calf urine, and its application to the control of potential misuse in cattle. The method involves purification on two solid-phase extraction cartridges (SPE C18 and SPE SiOH) and LC-(ESI+)-MS/MS measurements. The sensitivity and specificity of tandem quadrupole MS/MS allowed measurements at trace levels in both spiked and incurred samples. Good linearity was observed for all analytes from 0.12 ng to 12 ng on column.
The document details a developed analytical procedure for identifying 20-hydroxyecdysone (20E) and its main metabolites in biological matrices, specifically calf urine. The method utilizes solid-phase extraction purification followed by LC-(ESI+)-MS/MS measurements to detect trace levels of these compounds.
The method shows good linearity for all analytes from 0.12 ng to 12 ng on column.
20-hydroxyecdysone was detected as rapidly as 30 minutes after administration and up until 24 hours after the last administration.