Determination of semduramicin in poultry feed additive, premixture and compound feed by liquid chromatography and UV spectrophotometric detection after post-column derivatisation

Abstract

A new, simple and fit for purpose method based on liquid chromatography with UV spectrophotometric detection and post-column derivatisation (LC-UV-PCD) for the determination of semduramicin in poultry compound feed, premixtures and feed additive as well as its discrimination from other coccidiostats in poultry compound feed has been developed and single-laboratory validated. The concentration levels of the target analyte at which the validation experiments have been carried out varied between 12.8 and 51.3 mg kg(-1) in compound feed, covering the authorised levels of semduramicin according to European Union legislation. Furthermore, the method has been validated for a premixture sample containing semduramicin at 3 g kg(-1) and the feed additive containing semduramicin at 51 g kg(-1). The method developed involved a simple extraction of the coccidiostats with acetonitrile from the feed samples followed by a filtration of the supernatants. The resulting supernatants were submitted to chromatographic analysis. When analysing the feed additive and the premixture samples, the extraction solution was appropriately diluted prior to LC-UV-PCD analysis. The analytes were quantified through an external calibration curve prepared with pure semduramicin standards. The relative standard deviations for repeatability and for intermediate precision varied from 2.4 to 8.8% and from 2.6 to 8.8%, respectively, and the values for the relative recovery rate ranged from 89 to 95%. The limit of detection (LOD) and limit of quantification (LOQ) were estimated to be below 1 mg kg(-1) and 3 mg kg(-1), respectively. Moreover, the results showed a comparable performance profile, when using methyl isobutyl ketone instead of acetonitrile as extraction solvent.Based on the obtained method performance characteristics, the method is considered suitable for the determination of semduramicin in poultry compound feed at authorised level, in premixtures and in the feed additive, hence allowing the enforcement of the European Union legislation regarding the control and the monitoring in feedingstuffs.