Fig. 1

Schematic illustration of “AND” gate A1. a The principle of streptavidin mediated fluorescent quenching apparatus based on DNA strand displacement. b The PAGE analysis of strand displacing operations (DNA concentration was 1 μM). The gel is dyed by EB. c Relative variations of fluorescent intensity. FAM fluorescence was quenching by BHQ, decreasing fluorescent intensity. Here, variations represent the extent of decrease relative to original value. The error bars represent the standard deviations of three independent experiments. The true value table is shown in (d)