Validation of quick and highly specific quantitation method of mycotoxin in cocoa beans by high resolution multiple reaction monitoring technique for reference materials analysis

This article discussed a development, optimization, and validation of modified QuEChERS method with liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) operated in time-of-flight multiple-reaction-monitoring (TOF-MRM) mode for the analysis of ochratoxin A and aflatoxins (B1, B2, G1, G2) in cocoa beans. The recoveries for the optimized and validated method at 2 and 5 ng/g were in the range of 75.4–107.8 % with RSDs below 11.5 %. Good sensitivity was obtained for all mycotoxins with method limit of quantification oranged between 0.7 to 1.4 ng/g. New identification criteria was proposed using multiple reaction monitoring (MRM) transition product ions mass accuracy to prevent both false positive and negative. Finally, the proposed method was used to analyze mycotoxin residues in artificially contaminated cocoa beans samples for reference material production.