Most methods designed to provide accurate quantitation rely on a chromatographic separation followed by detection of the mycotoxins. Thin layer chromatography (TLC), High performance liquid chromatography (HPLC) and Gas Chromatography (GC) are the most commonly used methods for accurate quantitation.
Thin Layer Chromatography (TLC)
Microliter quantities of clean-up extract and standards are applied in a horizontal line near one edge of plate. This edge of the plate is placed in a tank containing an appropriate solvent system, which migrates through the sorbent layer, separating the components of the sample.
Mycotoxins are usually visualized as fluorescent spots under UV light, or plates can be sprayed with or exposed to various reagents to effect a chemical change in the mycotoxin that makes it visible. Quantitation is achieved by comparision of the intensity of the fluorescence or color of the sample spot with those of a series of standards.
High Performance Liquid Chromatography (HPLC)
HPLC is similar to TLC except that it differs in the the high efficiency sorbent is packed into a column and the solvent is pushed through with a high pressure pump.
After mycotoxins elute from the column, they immediately pass into a detector which usually measures fluorescence or absorbance of the mycotoxin. This can be compared with similar measurement of known concentration of standards to produce accurate quantitation.
Gas Chromatography
Gas chromatography are best choice for detection of trichothecenes.
When a gas chromatography is coupled with a mass spectrometer (GC-MS), the most reliable identification of GC peaks can be achieved. This method can be used to separate and identify complex mixture of trichothecenes with high sensitivity and selectivity.
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