Simultaneous multi-residue determination of twenty one veterinary drugs in poultry litter by modeling three-way liquid chromatography with fluorescence and absorption detection data

Abstract

A method for the simultaneous investigation of twenty one veterinary active ingredients in poultry litter basedon MCR-ALS modeling of three-way liquid chromatography with fluorescence and UV detection data ispresented. The chromatographic procedure was optimized in terms of both the nature of the organic solvent andthe pH of the mobile phase to maximize the resolution of the analytes. In order to improve the simultaneousextraction efficiency of the twenty one veterinary drugs, a simplex-centroid design with combinations of thethree components of the extracting mixture, i.e. MeOH, ACN and sodium phosphate buffer 10 mmol L?1 pH=3.50, was carried out. The second-order advantage was exploited in the analysis of highly complex samplescontaining unmodeled components. The qualitative and quantitative results showed that the application ofMCR-ALS was appropriate to resolve highly overlapped peaks in the presence of unknown matrix compounds. Limits of quantification, relative errors of prediction (REP) and average recoveries ranging from 0.02 to0.61 μg g?1, 3.09?9.35% and 91.0?105.6%, respectively, were obtained. Eventually, the method was successfullyapplied to the determination of active ingredients in five poultry litter samples collected from differentpoultry livestock in Argentina.