During the adsorption and desorption processes, Trilogy is simulating the digestive system of the animal that will be ingesting the binder product. Therefore, it's suggested targeting pHs similar in range. The following is a chart of pHs to assist you. If the target animal is a species not listed, please let Trilogy know, they will assist in finding the pH of the required species.

Trilogy's method was developed more for a monogastric system. With ruminants, some customers have chosen to test the first two stages of the system – testing at an adsorption pH of 6.5 and desorption of 2-3 depending on their target species. Other customers have opted to test an adsorption pH of 5 (simulating a combination of the rumen and abomasum) and desorption pH of 6.5-8 (simulating the intestines).

Regarding toxin concentrations, there are two methods for selecting these concentrations. The first method involves choosing a toxin concentration (for each toxin/analyte individually) based on an estimate of a real-world scenario that Trilogy would expect the feed additive product to bind. These concentrations typically fall in the 1 – 5ppm range depending on the mycotoxin. The toxin will be added to the phosphate buffer at this concentration, and the sample sent will then be challenged against the parameters Trilogy has defined. The second method is to select concentrations based on the regulations/suggestions set by the market where the product will be sold (i.e. US, European Union, etc). If the customer does not know these guidelines, Trilogy can try to assist with this.

For the inclusion rates, customers can choose a percent of binding material, such as 3%, or specify the amount of binder material per ton of feed, for example, 1kg/ton.

A mycotoxin binder or adsorbent is a substance that is added to animal feed in order to trap mycotoxins while in the gastrointestinal tract, preventing the toxin from entering the bloodstream through their gut where they can cause harm to the animal. Mycotoxin binders are used when other preventative measures have failed and when food and feedstuff cannot be regularly checked for contamination.

• Versatility: It has the ability to bind a wide range of mycotoxins in various pH conditions
• Retention: For many binders, the adsorption of mycotoxins is reversible and sensitive to pH changes
• Specificity: The specificity of mycotoxin binders is important as you don’t want the product to bind essential nutrients.
• Velocity of adsorption: Adsorbents are not selective for mycotoxins. They will bind other molecules present in the GI tract such as essential nutrients.
• Overall Safety: Overall safety of the material must be considered when deciding to incorporate a binder. 

For many binders, the adsorption of mycotoxins is sensitive to changes in pH. They tend to adsorb better under acidic conditions rather than neutral or basic conditions. The pH of the gastrointestinal tract of production animals rapidly changes, so retention of the bound mycotoxin with pH changes is the key.

Chemical and physical properties such as polarity and size of the mycotoxins can influence the efficiency of the adsorbent. An efficient binder should adsorb polar and non-polar as well as small and large mycotoxins. Clays, such as aluminosilicates, are commonly used since they are very efficient at binding high polarity and small size mycotoxins such as aflatoxin and can be modified to also bind non-polar and larger mycotoxins.

 The pH of the adsorbent itself can also play a role in the efficiency of the binder. So it is possible that the same clay from two different sources will result in different efficiency of the product.

During the in vitro binding analysis, the initial stage “adsorption” is the phase by which the mycotoxin adhers to the adsorbent material. This is ran at a pH similar to the stomach or foregut of the animal. During this stage, you are determining how much of the mycotoxin present in the buffered solution will bind to the adsorbent material.

Desorption is the opposite of adsorption. During this stage, you are determining how much of the previously bound mycotoxin will be released once the the material passes into the intestines or hindgut of the animal. pH is a key factor to the efficiency of the binding material. Some products may bind the mycotoxins well, however when the pH changes in the animal’s digestive system the mycotoxin can also be released easily allowing for the animal to still be harmed by the mycotoxin.

The overall percent efficiency of the binder is how much of toxin initially present in solution stays bound to the adsorbent throughout the digestive system and will be excreted from the animal.

If the product you are testing is already on the market, you will want to test with the dosage level that is suggested for feeding the product. However, if you are developing a new product, it is important to remember that you should target the lowest dosage possible to achieve maximum adsorption of mycotoxins in the shortest amount of time possible.

There are two methods of choosing the toxin concentration to test at. First, is to look at real world scenarios of the level of mycotoxins that could be found in the feed. These can typically fall in the range of 1 to 5 ppm depending upon the mycotoxin. The second method is to test at concentrations based on the regulated or suggested levels of toxin that can be present in the feed. You may wish to challenge your product by testing at 10 times the recommended levels of toxin that can be present.

During In vitro binding analysis, you are simulating the digestive system of the target animal. Therefore, the pH for both adsorption and desorption should be similar in pH of their digestive system. For example, if you’re intending to use the product for poultry, you may want to test at an adsorption pH 4.0 and desorption pH 6.5. This would correlate to the crop (pH 4.0-6.0) and intestines (pH 6.0-7.0).