Effects of the matrix and sample preparation on the determination of fluoroquinolone residues in animal tissues

The effects of aqueous-organic solvent extraction and enzymic digestion son ication procedure on the isolation of spiked fluoroquinolones from poultry tissue have been studied. The highest recovery from spiked tissue was obtai ned using a mixture of trichloroacetic acid-acetonitrile (8:2) as extractan t and an SDB1 cartridge for clean-up purposes. Validation data are presente d for enrofloxacin, ciprofloxacin, sarafloxacin and difloxacin. The spiking procedure (spike contact time, spike solvent and matrix) had a small influ ence on the recovery of fluroquinolones from poultry muscle or liver. The e ffects of a different extraction on the determination of incurred enrofloxa cin and its metabolite, ciprofloxacin, residues in poultry tissues have bee n investigated. The extraction procedures investigated - aqueous-organic so lvent extraction, enzymic digestion or sonication - all gave similar result s for incurred fluoroquinolone concentration in poultry muscle after correl ation for spike recovery. The highest results were obtained in poultry live r when enzymic digestion has been used. (C) 2001 Elsevier Science B.V. All rights reserved.