Poster Presentation
Quality & Analytical Methods

118-P

A novel cleanup method and stable ¹³C-labeled internal standards to improve accuracy and sensitivity of mycotoxin LC-MS/MS methods
M. PRINSTER (1), A. Schiessl (2), C. Brewe (1), D. Houchins (1)
(1) Romer Labs, Inc., Union, MO, U.S.A.; (2) Romer Labs Divison Holding GmbH, Tulln, Austria

The need for multi-mycotoxin analyses is increasing, and laboratories are increasingly using LC-MS/MS methods in their routine testing operations. A concern with LC-MS/MS can be interferences from matrix components leading to differences in analyte ionization. To overcome this ionization effect, fully ¹³C-labelled internal standards may be used to correct such mass signal intensities and ensure qualified analysis results. Stable ¹³C-labeled mycotoxins have advantages over another alternative, deuterated (²H) internal standards. Using ¹³C changes the total mass of the atom only slightly, while using deuterium, the mass doubles, thus, ²H labeled mycotoxins may show retention time shifts. Nowadays, highly sensitive mycotoxin detection methods are demanded by the food and feed safety market. To achieve low detection limits for multiple toxins, a novel rapid multi-mycotoxin sample cleanup method is being developed for LC-MS/MS. This poster presentation will demonstrate the initial results of this method. Furthermore, it will illustrate the importance of applying internal standards when performing quantitative mycotoxin analyses on an LC-MS/MS system. In this method, average recoveries determined from a spiked maize sample were >80% for total aflatoxins, >70% for ochratoxin A, and >90% for zearaleneone, deoxynivalenol, T-2 and HT-2 toxin. LODs of the in-house LC-MS/MS method applying a novel cleanup column purification together with ¹³C labeled internal standards were well in range with European requirements for infant food mycotoxin analysis.

© 2013 Copyright AACC International