Using Threshold DNA Strand Displacement to Construct a Half Adder

Abstract

DNA strand displacement has the advantages of product predictability, programmability and threshold, and it is often used to build DNA-based logic operation systems. In this paper, we use DNA strand displacement to have different reaction priorities in different length ranges of the toehold domain to form the effect of the threshold and construct the logical AND gate and XOR gate. Logical operations use single-stranded DNA as the input signal, and the brightness of the fluorescence is used to measure the results. Then, the logic AND gate and XOR gate are used as basic logic units to form a half adder in parallel. Finally, we use Visual DSD to simulate and analyze the logic AND gate, XOR gate and half adder. The simulation results show that the logic gates constructed in this paper have good theoretical feasibility and effectiveness. This work provides a potential design idea for DNA-based arithmetic function operations and more advanced logic operations.