Detection of low molecular weight toxins using an optical phase method of ellipsometry

The method of total internal reflection ellipsometry (TIRE), which records simultaneously two parameters Δ and Ψ related to the amplitudes and phases of p- and s-components of polarised light, respectively, was exploited here for detection of mycotoxins (T-2 and zearalenone). The above mycotoxins in sub-ppb concentrations were detected using TIRE in both direct and competitive immunoassay. The study of immune reaction kinetics allowed the evaluation of adsorption/desorption rates and the association constant for zearalenone. The investigation of grain products samples revealed the presence of high concentrations of T-2 (>600 ng/ml) in mould products.