Assay of the set of all Sudan azodye (I, II, III, IV, and Para-Red) contaminating agents by liquid chromatography-tandem mass spectrometry and isotope dilution methodology.
A high-throughput mass spectrometric method is presented for the simultaneous detection of Sudan I, II, III, IV, and Para-Red azodyes in foodstuff. The method is based on the use of deuterium-labeled internal standards and atmospheric pressure chemical ionization (APCI) in a triple-quadrupole instrument. The gas-phase breakdown pattern of each labeled and unlabeled analogue displays the naphthoic moiety as a common fragment. The search for the parents of this common species (parent ion scans) allows, by flow injection and in a single run, the evaluation of the presence of each polluting species spiked in typical foodstuffs. A detailed assay of each azodye was performed by LC-APCI and isotope dilution method, through the multiple reaction monitoring approach, using deuterium-labeled internal standards. Sudan dyes can be quantified above the threshold of 10 ppb except for Sudan Para-Red, for which the limit of quantification was 20 ppb, likely due to the different ionization efficiency.
Dipartimento di Chimica, Università della Calabria, cubo 12/C, I-87030 Arcavacata di Rende (CS), Italy. fmazzotti@unical.it
Fabio
F
Mazzotti
Leonardo
L
Di Donna
Loredana
L
Maiuolo
Anna
A
Napoli
Raffaele
R
Salerno
Ashiff
A
Sajjad
Giovanni
G
Sindona
D001391:Azo Compounds / Q000032:analysis; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004396:Coloring Agents / Q000032:analysis*; D005506:Food Contamination / Q000032:analysis*; D009284:Naphthols / Q000032:analysis; D053719:Tandem Mass Spectrometry / Q000379:methods*
D001391:Azo Compounds; D004396:Coloring Agents; D009284:Naphthols; C024336:1-phenylazo-2-naphthol; C033003:sudan red; C009213:Scarlet Red; C033006:sudan III