Structural study of thrombin binding DNA aptamers by the circular dichroism

Multiple types of logic gates based on a single G-quadruplex DNA strand

In this work, we demonstrate the use of a single DNA strand and G-quadruplex-specific dye NMM as a label-free switch for the construction of series of basic logic gates (YES, NOT, OR, INHIBIT, NOR, AND). The simple GT-rich sequence could be used to interact with several molecules (K⁺, thrombin, Hg²⁺, and Pb²⁺) to form different structures that can be distinguished by the label-free dye NMM. Our study showed that a single G-qudruplex DNA strand can function as multiple types of one-input and two-input logic gates with different combinations of input molecules.