Real-Time PCR-Coupled CE-SELEX for DNA Aptamer Selection

Figure 7

Competition assay with unlabeled I1-5 aptamer. Unlabeled “cold” I1-5 aptamer at 0, 1.25, 2.5, and 5 pmol as indicated were incubated with 500 μM BSA (indicated by the “+”) before addition of the P32-labeled I1-5 (represented by a star) aptamer. Again, the formation of DNA aggregates is present at the top of the lanes. As unlabeled DNA competitor increases, the amount of radiolabeled DNA trapped in the aggregates decreases as expected.