ABSTRACT
A reliable and sensitive procedure is presented for the analysis of erythromycin (ERY) and oleandomycin (OLE) in food of animal origin, such as meat, liver, kidney, raw milk and egg. The method is based on a solid-phase extraction clean-up with a cation exchange cartridge, a 9-fluoromethylchloroformate (FMOC) precolumn derivatization and a separation by HPLC with fluorometric detection. The selectivity is satisfactory enough to control ERY and OLE residues as not many interfering peaks are observed for various food matrices. The macrolides recoveries of the total procedure were low, although >50%. However, addition of an internal standard (roxithromycin) corrected for recovery to give satisfactory quantitative results for repeatability, linearity, detection and quantification limits and mainly accuracy.
Subject(s)
Anti-Bacterial Agents/analysis , Drug Residues/analysis , Erythromycin/analysis , Food Analysis/methods , Food Contamination/analysis , Oleandomycin/analysis , Animals , Chromatography, High Pressure Liquid/methods , Dairy Products/analysis , Fishes/metabolism , Fluorometry/methods , Humans , Meat/analysis , Reproducibility of ResultsABSTRACT
A reliable and sensitive procedure is presented for the analysis of streptomycin (STP) in food of animal origin, like meat, milk and honey. The method is based on a separation by ion-pair liquid chromatography with beta-naphthoquinone-4-sulfonate (NQS) postderivatization and fluorescence detection. The clean-up of the extract is done by solid-phase extraction, firstly with a cation-exchange cartridge and secondly with an octadecyl cartridge. The selectivity is very good and not many interfering peaks are observed for various food matrices. The streptomycin recovery of the total procedure is superior to 80%. The procedure is quantitatively characterized and repeatability, linearity, detection and quantification limits are very satisfactory. A special focus is given to STP residues in honeys and a survey on 64 commercial honeys is presented. For honey analysis, the HPLC method is compared with an immunoassay test (ELISA), and the possibility of using this test for screening with and without solid-phase extraction clean-up is also discussed.
