What technologies are available for mycotoxin analysis?
Several mycotoxin testing technology methods have been developed to detect and prevent the many threats to human and animal health that result from mycotoxin contamination. But not all testing methods are affordable, easy to use, or even reliable—which has proven to be a challenge for crop farmers, grain suppliers, mills, and cereal producers. Fortunately, advancements in research and development have produced mycotoxin testing technology that can be used more reliably in the field and non-laboratory settings.
In order to identify the best mycotoxin analysis methods for specific crops and for various points along the grain supply chain, it’s necessary to understand the different types of testing technology and their strengths and weaknesses.
ELISAs and lateral flow strips for mycotoxin testing
ELISAs, which use specific enzymes that cause a liquid sample to change color if a mycotoxin is present, came into popularity in the 1970s and are still being improved to increase ease of use and reliability. ELISA stands for “enzyme-linked immunosorbent assay.”
In 2005, EnviroLogix pioneered the first commercial lateral flow device (LFD) for detection of mycotoxins, QuickTox Kit for Aflatoxin. Lateral flow strips, similar to a pregnancy test, work by exposing a strip of test medium to a fluid sample to identify the presence of harmful mycotoxins. For specifics, read more about how immunoassays work.
ELISAs and lateral flow strips are not only reliable, making some older technologies obsolete, but they are easy for anyone to use. They do not require a trained lab technician in a mycotoxin laboratory to conduct these tests. They are more accessible than affinity columns and high-performance liquid chromatography because they do not require expensive equipment to use them. This freedom from expensive equipment means that these method are more affordable, and the simplicity of these methods contributes to speed and accuracy.
Affinity chromatography for mycotoxin testing
Affinity chromatography is a purification process of isolating and capturing a targeted molecule in a grain sample, which enables scientists to identify the presence of mycotoxins. The grain sample is extracted with a liquid which is poured into a column, similar in shape to a test tube, with a spigot at the bottom. The column contains a binding matrix that captures the targeted molecule when fluid passes through the binding matrix allowing the rest of the sample to exit the column through the spigot at the bottom. The column is then washed with buffer and then the bound mycotoxin is removed from the column by the addition of an elution buffer. Quantification of the mycotoxin can occur immediately upon elution if the affinity column is connected to an appropriate detector. Specific affinity columns with unique binding matrices are needed for each individual mycotoxin.
Affinity chromatography has been used since its development in the 1960s. Although it is reliable, affinity chromatography isn’t easy to complete and it can sometimes take days to conduct a test in a mycotoxin laboratory. Some improvements have been developed, such as automated high-pressure liquid chromatography (HPLC), which employs a pump to speed up the process, but it is still cumbersome and expensive.
Black light detection of mycotoxins
In the 1970s, ultraviolet light, also commonly referred to as black light, was commonly used to detect the presence of aflatoxins. This method, although affordable and easy to use compared to chromatography, is very limited in its ability to detect mycotoxins. Many mycotoxins do not produce byproducts that fluoresce (false negative), and certain materials may fluoresce and respond to the black light by glowing without the presence of mycotoxins (false positive).
Some of the most dangerous mycotoxins, such as vomitoxin, go undetected when using the black light detection method and present a risk of contamination. Studies have shown that black light detection of mycotoxins is can produce up to 60% false positive and false negative results. Deemed unreliable, black light has been mostly abandoned in favor of more comprehensive mycotoxin detection methods.
Scientific advancements led to the development of mycotoxin analysis methods that are easier to use, deliver results faster, and are more affordable.
Points to consider when choosing a mycotoxin testing method
Mycotoxin testing technology has improved over the years, enabling grain and feed growers and suppliers to test crops with more confidence. The ideal mycotoxin detection method provides accurate results every time—without too much cost or hassle—making food safety a repeatable and affordable priority.