Simultaneous Determination of the Residual Amounts of Chloramphenicol and Chloramphenicol Palmitate in Food Products using Liquid Chromatography–Mass Spectrometry

• Published in: Moscow University chemistry bulletin 2020-11, Vol.75 (6), p.333-339
• Main Authors: Amelin, V. G., Bol’shakov, D. S.
• Format: Article
• Language: English
• Subjects: Acetonitrile; Additives; Adducts; Aquaculture; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Chloromycetin; Chromatography; Deionization; Electrospraying; Food products; Ions; Liquid chromatography; Mass spectrometry; Meat; Negative ions; Parameter identification; Pork; Quadrupoles; Scientific imaging; Spectroscopy
• ISSN: 0027-1314; 1935-0260
• DOI: 10.3103/S0027131420060024

A simple method for sample preparation, identification, and determination of chloramphenicol and chloramphenicol palmitate in food products by ultrahigh performance liquid chromatography–high-resolution quadrupole-time-of-flight mass spectrometry based on the exact values of the mass of ions formed during ionization by electrospray is proposed. The objects of analysis are meat (beef, pork, and poultry) and aquaculture products (fish). Sample preparation consisted of extracting the target components with acetonitrile and diluting the extract by a factor of two with deionized water. Five parameters were used for identification: retention time, accuracy of the monoisotopic mass of parent ions, the presence and accuracy of the monoisotopic mass of the product ions, mSigma parameter (conformity of theoretical isotopic distribution to the practical one), and the monoisotopic mass of the adducts. The features of determining chloramphenicol and chloramphenicol palmitate—which are caused by the appearance of deprotonated molecules and adducts with chloride, formate, and trifluoroacetate ions in an electrospray device during the detection of negative ions—are considered. In addition, in the first chromatography of the extract, chloramphenicol ( t R = 4.0 min) is eluted, and chloramphenicol palmitate ( t R = 6.5 min) is eluted during the repeated chromatography by an acetonitrile–water (1 : 1, vol) mixture. A method for the determination of chloramphenicol and chloramphenicol palmitate by the method of standard additives using the summation of the peak areas of all the recorded ions is proposed. The range of the determined concentrations of chloramphenicol and chloramphenicol palmitate is 0.1–10 and 0.5–50 ng/g, respectively. The relative standard deviation of the results of the analysis does not exceed 0.15. The duration of the analysis is 50–60 min.