Agriculture Reference
In-Depth Information
ultrahigh-performance liquid chromatography (HPLC and UHPLC). GC was fre-
quently used for this purpose in the 1990s. However, the obvious drawbacks of
GC-based methods relate to the need for time-consuming sample preparation and
derivatization of analytes, which have led to their reduced use in mycotoxin analysis
[49]. On the other hand, LC coupled to either conventional detectors [ultraviolet (UV)
detector, diode array detector (DAD),
fluorescence detector (FLD), and photodiode
array detector (PDA)] or mass spectrometers is currently the most frequently applied
separation technique. Note that conventional detectors are selective only for a limited
number of toxins, and are thus less versatile than MS detection. LC-based methods are
also used to con
rm results of novel rapid screening techniques [47,50].
8.3.1 Liquid Chromatography
-
Mass Spectrometry-Based Methods
Currently, the analysis of mycotoxins relies largely on LC separation employing
reversed-phase (RP) columns in combination with MS using different mass analyzers.
Such methods represent the reference and de
nitive protocols for mycotoxin analy-
sis [18]. Although most of the published LC
ows have focused on
simultaneous determination of structurally related mycotoxins in single food/feed
matrices, several studies have described successful integration of analysis of multiple
nonrelated mycotoxins into a single determinative LC-MS method. This was made
possible by substantial advances in MS instrumentation that resulted in suf
-
MS-based work
ciently
sensitive and selective high-throughput broad-scope mycotoxin analysis. In these
LC
MS methods, various combinations of LC operated in either high-pressure (HP)
or ultrahigh-pressure (UHP) mode with low-resolution (LR) tandem MS or high-
resolution (HR) MS have been used.
The most recently published studies aiming at rapid analysis of multiple myco-
toxins using LC
-
53]. In some of these studies,
mycotoxins were analyzed simultaneously with other food contaminants or natural
toxins, such as pesticides, plant toxins, marine toxins, and/or veterinary
drugs [24,29,52]. The average number of mycotoxins analyzed by these methods
was between 30 and 40. Typical groups of mycotoxins for which analytical standards
are commercially available (e.g., trichothecenes, enniatins, fumonisins, a
-
MS are Refs [24,28,29,48,51
-
atoxins,
ergot alkaloids, alternaria toxins, ZON, OTA, and PAT) were tested. The only
exceptions were multimycotoxin methods described by Sulyok et al. [48], Abia
et al. [51], and Varga et al. [53], who developed procedures capable of simultaneous
analysis of 106, 320, and 191 mycotoxins and other toxic or potentially toxic fungal
secondary metabolites, respectively. Not only cereals, nuts, and related products were
used for evaluation of the method recoveries, but other important matrices such as
baby foods, fruits, seeds, spices, honey, milk, eggs, meat, alcoholic and nonalcoholic
beverages, soybeans, and cheese were also included.
Regarding the separation step, (U)HPLC systems are usually applied for multi-
mycotoxins analysis. An ongoing development in UHPLC instrumentation allows
separation to be performed under substantially higher pressures using chromato-
graphic columns with a sub-2
m stationary-phase particle size, which generally result
in narrower chromatographic peaks and lower overall run times. The effective LC
μ
