Fig. 5

Determining the optimal ratio of colloidal gold and mAb 3A2 for conjugation. a A fixed amount of colloidal gold (200 μL) was mixed with an increasing amount, from 0 to 1 mg/mL (30 μL), of mAb 3A2. As the concentration of the antibodies increased, the color of the conjugated antibody-colloidal gold became pink. b The curves of OD528 values represented the absorbance from conjugated colloidal gold