Determination of nifursol metabolites in poultry muscle and liver tissue. Development and validation of a confirmatory method
van Rhijn, J.A.
TNO Kwaliteit van Leven
A method is described for the identification and quantitative determination of 3,5-dinitrosalicylic acid hydrazide (DSH), the marker residue of nifursol metabolites in poultry (turkey, broiler) muscle and liver tissue. The method is based on the acid-catalysed hydrolysis of tissue-bound metabolites to free DSH and in situ derivatisation with 2-nitrobenzaldehyde to the corresponding nitrophenyl derivative NPDSH. A structural analogue of DSH, 4-hydroxy-3,5- dinitrobenzoic acid hydrazide (HBH) was synthesised to serve as an internal standard. The analytes were isolated from the matrix by liquid-liquid extraction with ethyl acetate. Determination was performed by LC-MS/MS with negative electrospray ionisation. The [M - H]+ ions of NPDSH and NPHBH at m/z 374 were fragmented by collision induced dissociation (CID) producing transition ions at m/z 182, 183 and 226. The transition ions at m/z 182 and 226 were selected for monitoring of NPDSH while the transition ion at m/z 183 was selected for NPHBH. The method has been validated according to the EU criteria of Commission Decision 2002/657/EC at 0.5, 1.0 and 1.5 μg kg-1 in muscle and liver tissue. A decision limit (CCα) was obtained of 0.04 and 0.025 μg kg-1 in muscle and liver, respectively. Similarly a detection capability (CCβ) was obtained of 0.10 and 0.05 μg kg-1 in muscle and liver, respectively. The introduction of HBH as an internal standard did not lead to a significant improvement of the quantitative performance of the method. In fact for liver better performance characteristics were obtained when the IS was not taken into account. Nevertheless, as a qualitative marker for recovery, HBH could still be very useful in the analysis of unknown samples. © The Royal Society of Chemistry 2005.
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Food and Chemical Risk Analysis
3,5 dinitro n' (5 nitrofurfurylidene)salicylhydrazide
4 hydroxy 3,5 dinitrobenzoic acid hydrazide
acetic acid ethyl ester
nitrobenzoic acid derivative
liquid liquid extraction
Analyst, 130 (5), 763-771