Gliadin (Gluten) Total

With the RIDASCREEN® Gliadin test it is possible to detect gluten from wheat, rye and barley quantitatively with a detection limit of 3 ppm. It works in raw as well as in processed foods. 

The RIDASCREEN® Gliadin test uses the R5 monoclonal antibody which is now a Codex Alimentarius Type 1 (defining) method.

Gluten is the characteristic term for the protein mixture of glutelins and gliadins (prolamines) found in cereals. The proportion of glutelin to gliadin in the protein mixture is approximately the same. One exception are starches : Their prolamine / gluten proportion is depending on the washing degree of the starches (factor between 1.6 and 2.6). There exist various groups of gliadins. Their contents vary from cereal to cereal. Gluten is found in many cereal products, however, due to its inherent physicochemical properties as binding and extending agent it is commonly used as an additive in foods. 

Detection of gluten plays a role in the quality control and selection of foods for individuals with gluten intolerance. In cases of gluten intolerance enteropathy, celiac disease, sprue and related allergic reactions, a diet free from gluten contained in wheat, rye barley and in some cases oat would be necessary. 

In the "Codex Standard for gluten free food" the term "gluten free" is defined as follows: " In accordance with this standard "gluten free" means, that the total amount of the used gluten of wheat, rye, barley and oat in the products or those crossed species in food or ingredients is not more than 200 ppm (mg/kg) on the dry substance basis".

A limit of Gluten to 20 ppm is in discussion. Prolamines are those gluten fractions, which can be extracted with ethanol (40 - 70%). The prolamine content of gluten generally is 50%. Therefore, the limit for prolamines is 100 ppm (mg/kg) corresponding to an approx. gluten content of 0.02%. 

The common detection of gluten is based on microscopic, electrophoretic and chromatographic methods. These methods seldom yield acceptable quantitative results, particularly in the case of processed and cooked foods.

In addition, these methods are time consuming and require expensive laboratory equipment. In accordance with the "Codex Standard for gluten free goods" (temporary draft) the gluten detection in foods and ingredients has to be based on an immunological method and the detection limit should be at least 10 ppm in products based on dry substance.  

Microtiterplate format:  96 well Detection limit: 1.5 ppm gliadin corresponding to 0.0003 % gluten 

Incubation time:  1h 30 min 

Sample preparation:  homogenization and extraction 

Specificity: the R5 monoclonal antibody reacts with the gliadin fraction from wheat, corresponding prolamines from rye and barley.

Samples per kit: up to 42 

Standards: 0 / 5 / 10 / 20 / 40 / 80 ppb 

Measurement:  microtiter plate reader (450 nm)