Figure 5. Sensitivity determination of sandwich ALISA against pure SEB toxin.

(A) Sandwich dot-ELISA; (B) Sandwich plate ELISA. (A) SEB toxin was added to IgY pre-coated nitro cellulose membrane at following concentrations A- 10 μgmL⁻¹; B- 5 μgmL⁻¹; C- 1 μgmL⁻¹; D- 0.5 μgmL⁻¹; E- 0.25 μgmL⁻¹; F- 0.1 μgmL⁻¹; G- 0.05 μgmL⁻¹; H- 0.01 μgmL⁻¹ and then SEB toxin was probed with biotinylated anti SEB aptamer. LOD of the assay was determined as 50 ngmL⁻¹. (B) Various concentrations of SEB were added to IgY pre-coated microtiter plate wells. The indirect ALISA was performed using biotinylated anti SEB aptamer. For blank control PBS was used. The graph shows average ± SD of the absorbance reading in independent triplicates.