Fig. 3. Reactivity response curves in indirect ELISA against AG–HSA conjugates (A) and icELISA against free AG (B). In both ELISAs, concentration of AG–HSA conjugates was 5 μg mL⁻¹. In icELISA (B), A₀ and A corresponds the absorbance in the absence and presence of AG. A dotted line represents linearized curve for AG with the determination range from 1.95 to 62.5 ng mL⁻¹.