A liquid–liquid extraction procedure followed by a low temperature purification step for the analysis of macrocyclic lactones in milk by liquid chromatography–tandem mass spectrometry and fluorescence detection

• Published in: Analytica chimica acta Vol. 705; no. 1; pp. 24 - 29
• Main Authors: Rübensam, Gabriel, Barreto, Fabiano, Hoff, Rodrigo Barcellos, Kist, Tarso Ledur, Pizzolato, Tânia Mara
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 31.10.2011; Elsevier
• Subjects: Analytical chemistry; Animals; Avermectins; Cattle; Chemistry; Chromatographic methods and physical methods associated with chromatography; Chromatography, Liquid - economics; Chromatography, Liquid - methods; Coefficient of variation; Exact sciences and technology; Extraction; Fluorescence; Lactones; Lactones - analysis; Lactones - chemistry; Lactones - isolation & purification; Liquid chromatography; Liquid chromatography–fluorescence detection; Liquid chromatography–tandem mass spectrometry; Liquid-liquid extraction; Liquid-Liquid Extraction - economics; Liquid-Liquid Extraction - methods; Low temperature purification; Macrocyclic compounds; Macrocyclic Compounds - analysis; Macrocyclic Compounds - chemistry; Macrocyclic Compounds - isolation & purification; Mass spectrometry; Milk; Milk - chemistry; Other chromatographic methods; Purification; Sensitivity and Specificity; Spectrometric and optical methods; Tandem Mass Spectrometry - economics; Tandem Mass Spectrometry - methods; Avermectins; Extraction; Liquid chromatography–fluorescence detection; Liquid chromatography–tandem mass spectrometry; Low temperature purification; Fluorescence; Fluorescence spectrometry; Chemical enrichment; Sample preparation; Detection limit; Ungulata; Quantitative analysis; Low temperature; Variation coefficient; Milk; Fluorescence detector; Purification; Bovine; Liquid liquid extraction; Sample; Lactone; Liquid chromatography; Matrix effect; Method; Vertebrata; Mammalia; Mass spectrometry MS/MS; spectrometry; Regulation; Artiodactyla; Detection; Liquid chromatography-fluorescence; Liquid chromatography-tandem mass
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2011.02.041

In this work a method is proposed and demonstrated for the analysis of the macrocyclic lactones abamectin, doramectin, eprinomectin, ivermectin and moxidectin in bovine milk by liquid chromatography coupled to mass spectrometry (LC–MS/MS) and liquid chromatography with fluorescence detection (LC–FL). The method is based on liquid–liquid extraction followed by a low temperature purification (LLE–LTP) step. Moreover, the proposed method was validated according to the Commission Decision 2002/657/EC, using LC–MS/MS and LC–FL for confirmatory and quantitative analysis, respectively. For LC–MS/MS the recovery rates observed ranged from 101.2 to 141.6% with coefficient of variation from 2.6 to 19.8%. For LC–FL the recovery rates observed ranged from 100.2 to 105% and coefficient of variations from 2.9 to 8.8%. Matrix effects were negligible due to the low temperature purification step. The quantification limits were far below the maximum limits established by regulations of all countries consulted. The proposed method proved to be simple, easy, and adequate for high-throughput analysis of a large number of samples per day at low cost.