i-TRA Turbidimetric is a latex agglutination test based on the turbidimetric principle for the quantitative in vitro determination of transferrin (Tf) in human feces. The reagent contains latex particles coated with goat IgG anti-human Transferrin in a Tris buffer. The Tf present in the patient stools solution reacts with the coated latex particles causing an agglutination that can be measured with a photometer. The degree of turbidity is proportional to the concentration of Tf in the sample.