Fig. 1.

Comparison of the direct assay (this work) and indirect microsphere immunoassay [33]. In an indirect assay (A), sample, antibodies and mycotoxin-BSA conjugated beads (a) are incubated so that there is competition between the conjugated mycotoxins on the bead and the free mycotoxins in the sample (b). After incubation, the beads are trapped by a magnet and the non-bound reagents washed away (c). The beads are released and an anti-mouse-RPE is added (d). After incubation, the beads are trapped again and non-bound anti-mouse-RPE is washed away (e). After release, the beads are measured (f). In the much simpler direct assay presented in this work (B), sample, mycotoxin-RPE conjugate labels and antibody-coupled beads are incubated (g). Labelled and free mycotoxins compete for antibodies on the beads (h). Then beads are trapped by a magnet and the non-bound reagents washed away (i). Beads are released and measured (j). This is done all-in one for three different mycotoxins in one well (C)