Figure 10

The preliminary aptamer experiments are based on the DNA molecule obtained from annealing ssDNA1: 5'-CAAGCTTGGTTTCGATAGGTA-3' with ssDNA2: 5'-ATCGTTTCCAAGCTTG-3'. For the pseudo-aptamer binding experiment a solution of annealed ssDNA1 and SSDNA2 molecules was exposed to ssDNA3: 5'-TACCT-3' (which anneals to the remaining AGGTA complement on ssDNA1). The target 5-base ssDNA is introduced subsequent to obtaining a toggler-type capture of the aptamer molecule (properly annealed). The aptamer experiment is referred to above as a pseudo-aptamer experiment due to its simplification to a DNA annealing detection. The short blockades in (a) result from ssDNA translocation by the un-annealed or partially annealed (mismatched) ssDNA components. The brief blockade in (b) is hypothesized to be due to capture with the overhang end entering first (and subsequent rapid melting of the annealed molecule – akin to that seem in the DNA hairpin experiments [12]).