Automated hollow-fiber liquid-phase microextraction coupled with liquid chromatography/tandem mass spectrometry for the analysis of aflatoxin M1 in milk

An automated hollow fiber liquid-phase microextraction (HF-LPME) coupled with liquid chromatography/tandem mass spectrometry (LC-MS/MS) method was developed for the extraction and determination of aflatoxin M-1 (AFM(1)) in milk samples. Parameters affecting the extraction efficiency, such as the extraction phase, matrix conditions, extraction time and temperature, were investigated. Under the optimal conditions (ratio of water to milk, 4:1; extraction time, 50 min; extraction temperature, 50 degrees C; extraction phase, 50 mg L-1 anti-AFM(1) antibody in PBS buffer solution; volume of HCl solution, 250 mu L; agitation speed, 250 rpm), the matrix-matched calibration curve for AFM(1) determination showed good linearity in the range of 0.25-5 mu g kg(-1). The enrichment factor (EF) reached 48, and the limits of detection and quantification were 0.06 and 0.21 mu g kg(-1), respectively. The developed method was successfully applied for the extraction of AFM(1) from spiked milk samples, with recoveries from 61.0% to 106.7%. The method was highly specific to AFM(1) analysis, and the results demonstrated that the method can be automated, inexpensive, and free from interference. (C) 2015 Elsevier B.V. All rights reserved.