Search

This paper presents a multi-residue analytical method for 210 drugs in pork using ultra-high-performance liquid chromatography-Q-Trap tandem mass spectrometry (UPLC–MS/MS) within 20 min via positive ESI in scheduled multi-reaction monitoring (MRM) mode. The 210 drugs, belonging to 21 different chemical classes, included macrolides, sulfonamides, tetracyclines, β-lactams, β-agonists, aminoglycosides, antiviral drugs, glycosides, phenothiazine, protein anabolic hormones, non-steroidal anti-inflammatory drugs (NSAIDs), quinolones, antifungal drugs, corticosteroids, imidazoles, piperidines, piperazidines, insecticides, amides, alkaloids and others. A rapid and simple preparation method was applied to process the animal tissues, including solvent extraction with an acetonitrile/water mixture (80/20, v/v), defatting and clean-up processes. The recoveries ranged from 52% to 130% with relative standard deviations (RSDs) < 20% for spiked concentrations of 10, 50 and 250 μg/kg. More than 90% of the analytes achieved low limits of quantification (LOQs) < 10 μg/kg. The decision limit (CCα), detection capability (CCβ) values were in the range of 2–502 μg/kg and 4–505 μg/kg, respectively. This method is significant for food safety monitoring and controlling veterinary drug use. [ABSTRACT FROM AUTHOR]

The enantiomeric separation of eight pesticides including bitertanol ( 1), diclobutrazol ( 2), fenbuconazole ( 3), triticonazole ( 4), imazalil ( 5), triapenthenol ( 6), ancymidol ( 7), and carfentrazone-ethyl ( 8) was achieved, using normal-phase high-performance on two cellulosed-based chiral columns. The effects of isopropanol composition from 2% to 30% in the mobile phase and column temperature from 5 to 40 °C were investigated. Satisfactory resolutions were obtained for bitertanol ( 1), triticonazole ( 4), imazalil ( 5) with the (+)-enantiomer eluted first and fenbuconazole ( 3) with the (-)-enantiomer eluted first on Lux Cellulose-2 and Lux Cellulose-3. (+)-Enantiomers of diclobutrazol ( 2) and triapenthenol ( 6) were first eluted on Lux Cellulose-2. (-)-Carfentrazone-ethyl ( 8) were eluted first on Lux Cellulose-2 and Lux Cellulose-3 with incomplete separation. Reversed elution orders were obtained for ancymidol (7). (+)-Ancymidol was first eluted on Lux Cellulose-2 while on Lux Cellulose-3 (-)-ancymidol was first eluted. The results of the elution order at different column temperatures suggested that column temperature did not affect the optical signals of the enantiomers. These results will be helpful to prepare and analyze individual enantiomers of chiral pesticides. Chirality 27:32-38, 2015. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

A fast method for the simultaneous determination of 14 antiviral drugs and relevant metabolites in chicken muscle by ultra-high liquid chromatography tandem mass spectrometry (UPLC–MS/MS) was developed. The analytes included anti-influenza drugs (amantadine, rimantadine, oseltamivir, oseltamivir carboxylate, memantine, arbidol, and moroxydine), anti-herpes drugs (acyclovir, ganciclovir, famciclovir, penciclovir, ribavirin and its main metabolite TCONH 2 ), and an immunomodulator (imiquimod). The samples were pretreated using a modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method. The determination of the target compounds was conducted in less than 11.0 min, and specificity was ensured by the use of multiple reaction monitoring (MRM) acquisition mode. Good linearities ( R 2 > 0.9928) were obtained in the range of 0.1–100 μg/L, and the recovery rates were 56.2–113.4% with RSDs of 1.7–10.3% for intra-day precision and 2.4–8.8% for inter-day precision. The LODs and LOQs of all analytes were in the ranges of 0.02–1.0 and 0.05–2.5 μg/kg, respectively. An analysis of real samples suggested that this method is simple, sensitive, reliable and practical for the detection of antiviral drugs in animal tissue. [ABSTRACT FROM AUTHOR]