Mycotoxins thin-layer chromatography

Fluorescence may by induced using labeled mono- or polyclonal antibodies raised against the compound of interest. This technique has been used successfully to detect the presence of okadaic acid in cultures of Prorocentrum lima, and, further, to estimate quantities of the compound in individual cells.110 Immunofluoresence in combination with thin layer chromatography and ELISA techniques have also been used to detect multiple haptens in mycotoxin families.111112... 

Thin-layer chromatography (TLC) is a widely used analytical technique for many investigative purposes. Detection of mycotoxins by means of TLC has been in use for many years. Official methods of analysis often rely on these techniques for both identification and quantification of several mycotoxins [1]. 

Thin-layer chromatography and HPTLC offer many possibilites for the determination of mycotoxins in plant or animal samples. Plant samples usually contain higher concentrations of mycotoxins, but analysis of animal tissues may be necessary either to confirm a suspected mycotoxicosis or to detect potential residues for human food. Many official methods are available, based on TLC, and the recent development of HPTLC also offers many possibilities for the detection and quantitation of several mycotoxins in various biological samples. 

The ELISA tests are preferred because they require low volume of the sample and fewer clean-up procedures of the extracted sample compared to the conventional methods like TLC (thin layer chromatography) and HPLC (high-performance liquid chromatography). ELISA tests are rapid, simple, specific, sensitive and portable for use in the field for the detection of mycotoxins in foods and fodder (Zheng et al. 2005). 

Screening tests for the trichothecene mycotoxins are generally simple and rapid but, with the exception of the immunochemical methods, are nonspecific. A number of bioassay systems have been used for the identification of trichothecene mycotoxins.73 Although most of these systems are very simple, they are not specific, their sensitivity is generally relatively low compared to other methods, and they require that the laboratory maintain vertebrates, invertebrates, plants, or cell cultures. Thin-layer chromatography (TLC) is one of the simplest and earliest analytical methods developed for myco-toxin analysis. Detection limits for trichothecene mycotoxins by TLC is 0.2 to 5 ppm (0.2 to 5 pg/ mL). Therefore, extracts from biomedical samples would have to be concentrated 10- to 1,000-fold to screen for trichothecene mycotoxins. 

Sokolovic, M. Simpraga, B. (2006). Survey of trichothecene mycotoxins in grains and animal feed in Groatia by thin layer chromatography. Food Control, Vol. 17, No. 9, (September 2006), 733-740, ISSN 0956-7135. 

The separatory power of a wide range of chromatographic methods can be used as a final cleanup stage before determination of a specific mycotoxin, with thin-layer chromatography (TLC), in either one- or two-dimensional mode, LC, and GC being the most common. 

See also Food and Nutritional Analysis Mycotoxins. Immunoassays, Techniques Enzyme Immunoassays. Liquid Chromatography Food Applications. Mass Spectrometry Food Appiications. Thin-Layer Chromatography Oven/iew Principles. 

Chromatographic methods used with mycotoxins include thin layer chromatography (TLC), liquid chromatography (LC), gas chromatography (GC), and LC coupled to mass spectrometry (LC-MS). 

Berny, P. Jaussaud, P. Durix, A. Ravel, C. Bony, S. Rapid determination of the mycotoxin lolitrem B in endophyte-infected perennial ryegrass by high-performance thin-layer chromatography A validated assay. J. Chromol. 1997, 769, 343. 

Published applications of TLC or HPTLC are dedicated to different topics in food analysis. With approximately 20% of all published method in the last 50 years, the analysis of dyes and pigments are the largest part of application followed by analysis of fatty acids, lipids, phospholipids and mycotoxins [162, 163], Although neither paper nor thin-layer chromatography plays a major role for routine analysis of berry anthoeyanins the value of these methods for research oriented work should never be imderestimated. 

Since NIV occurs as a co-contaminant with other trichothecene mycotoxins, it is often analyzed simultaneously with the co-contaminants rather than alone. Analytical methods developed so far include thin layer chromatography (TLC) capillary gas chromatography (GC) with electron-capture detection (BCD), flame ionization detection (FID), or mass spectrometric detection (GC/MS) high-performance liquid chromatography (HPLC) with ultraviolet (UV), fluorescence, or mass spectrometric detection supercritical fluid chromatography (SFC) and time-of-flight mass spectrometry (LC/TOF-MS). 

This review focuses on the nonproteinaceous toxins elaborated by fungi (mycotoxins) and plants for two reasons Historically, mycotoxins and plant toxins have been important in food safety considerations, and, in general, proteinaceous toxins are not usually analyzed by thin-layer chromatography (TLC) procedures. With the exception of the paralytic shellfish poisons, TLC methods have been used seldom in the determination of seafood toxins. The TLC method for saxitoxin developed by Buckley et al. (1) has been used extensively in the analyses of the saxitoxins (2). Reference 3 is an excellent review of seafood toxins. 

Nesheim S. and Trucksess, M.W. (1986). Thin-layer chromatography/high-performance chromatography as a tool for mycotoxin determination. In ... 

The most common assay to determine mycotoxins is based on a quick solvent extraction (methanol-water, ethanol, chloroform, etc.) of the mycotoxin. The extract is then filtered and quantified via ELISA (enzyme-linked immunoassay) columns. The use of minicolumns is the most common because it is fast, repeatable, and reliable, and requires little expertise to run the assay. The test usually takes 5 minutes, so it allows processors to make important decisions about the acquisition and economic value of the grain. Other more time-consuming and complicated tests are thin-layer chromatography or other chromatographic techniques based on fluorescence or UV detectors. The main advantage of these tests is the identification of specific types of mycotoxins. 

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