Liquid Chromatography for the Determination of Mycotoxins in Foods by: R. Romero-González, J. L. Martínez Vidal, and A. Garrido Frenich
Despite of the intentional use of chemicals, nowadays food contamination due to natural toxicants is also a mayor public concern. Mycotoxins are secondary metabolites produced by many species of fungi and they are one of the major contaminants of agricultural products. Because their high toxicity, many countries have set up regulations for their control in foods of plant origin for human. In order to fulfil the requirements described in these regulations, sensitive, selective and reliable analytical methods have been developed in order to determine as many mycotoxins as possible in one single analysis. Traditionally mycotoxins are mainly determined by immunoassay screening methods or by single compound chromatographic analytical methods, based on immunoaffinity column cleanup followed by a separation step using thin layer chromatography (TLC), gas chromatography (GC) or liquid chromatography (LC), which were coupled to conventional detectors such as electron capture detection (ECD), fluorescence or UV-visible detection. In some cases, especially when fluorescence detection was used, it was necessary to include a pre or postcolumn derivatization step in order to increase the detection capabilities of the analytical method. However, the application of hyphenated chromatographic techniques, especially LC coupled to mass spectrometry (MS) and LC-MS/MS, has several advantages including simple treatment, due to further clean up procedures with immunoaffinity columns can be avoided, rapid determination and high sensitivity. Furthermore, they can be used for the simultaneous determination of several types of mycotoxins in contaminated food samples, although the number of developed methods is still limited. Despite of the determination of regulated mycotoxins, it is important to detect mycotoxins for which standards are not commercially available as well as metabolites produced by fungi involved in food spoilage, and LC coupled to other type of analyzers such as time of flight (TOF), provides valuable information related to these compounds. An overview of liquid chromatographic methods, providing general aspects regarding the determination of mycotoxins in food and emphasizing the use of hyphenated techniques is presented. Advantages and disadvantages of chromatographic techniques are also evaluated, indicating the new advances which are mainly focused on the reduction of the analysis time. These advances allow the application of the developed methods for the determination of multicomponent mycotoxins in routine analysis or in monitoring programs, in which a large number of samples must be analyzed.
Chapter 1 Introduction 1
Chapter 2 Presence of Mycotoxins in Food 3
Chapter 3 Sample Preparation 9
Chapter 4 Chromatographic Methods for Mycotoxin Analysis 21
Chapter 5 Conclusion 55