Basic operators (AND, OR, and NOTgate) have already been realized in DNA reacting systems; thus, the XORgate could be realized, in theory, by combining these operators. However, the combinational circuit is highly complex because each XORgate requires two ANDgates, an ORgate, and two NOTgates. Accordingly, in this report, we focused on the XORgate as an operator for molecular programming and aimed to design a XORgate having a simple reacting system without the basic operators.
Our designed XORgate had two advantages. First, the design was simple, and the number of DNA strands on the designed XORgate was less than half that on the XORgate in the combination circuit. Second, the designed XORgate operated faster than the XORgate in the combination circuit. The designed XORgate functioned alone; thus, the number of strand displacement reactions was reduced, and we succeeded in accelerating the response time. In this way, the XORgate designed herein was superior to the XORgate in the combination circuit in terms of cost and performance.
Since the XORgate could prevent from interfering between two inputs, we designated this XORgate the “DNA Interference Canceller”.