Determination of chloramphenicol residues in meat, seafood, egg, honey, milk, plasma and urine with liquid chromatography-tandem mass spectrometry, and the validation of the method based on 2002/657/EC.
A simple and rapid method for the determination and confirmation of chloramphenicol in several food matrices with LC-MS/MS was developed. Following addition of d5-chloramphenicol as internal standard, meat, seafood, egg, honey and milk samples were extracted with acetonitrile. Chloroform was then added to remove water. After evaporation, the residues were reconstituted in methanol/water (3+4) before injection. The urine and plasma samples were after addition of internal standard applied to a Chem Elut extraction cartridge, eluted with ethyl acetate, and hexane washed. Also these samples were reconstituted in methanol/water (3+4) after evaporation. By using an MRM acquisition method in negative ionization mode, the transitions 321-->152, 321-->194 and 326-->157 were used for quantification, confirmation and internal standard, respectively. Quantification of chloramphenicol positive samples regardless of matrix could be achieved with a common water based calibration curve. The validation of the method was based on EU-decision 2002/657 and different ways of calculating CCalpha and CCbeta were evaluated. The common CCalpha and CCbeta for all matrices were 0.02 and 0.04 microg/kg for the 321-->152 ion transition, and 0.02 and 0.03 microg/kg for the 321-->194 ion transition. At fortification level 0.1 microg/kg the within-laboratory reproducibility is below 25%.
Rønning
Helene Thorsen
HT
Norwegian School of Veterinary Science, Section for Food Safety, P.O. Box 8146-Dep. 0033 Oslo, Norway.
Einarsen
Kristin
K
Asp
Tone Normann
TN
D000818:Animals; D002138:Calibration; D002701:Chloramphenicol / Q000032:analysis* / Q000097:blood / Q000652:urine; D002853:Chromatography, Liquid / Q000379:methods*; D004350:Drug Residues / Q000032:analysis*; D005504:Food Analysis; D006722:Honey / Q000032:analysis; D008461:Meat Products / Q000032:analysis; D008892:Milk / Q000737:chemistry; D015203:Reproducibility of Results; D017747:Seafood / Q000032:analysis; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
D002701:Chloramphenicol