Novel Sequential DNA Circuits Using DNAzymes

DNA circuits, consisting of DNAzyme library logic gates that relay DNA strand displacement reactions, have been proven to harness massive parallel computing abilities in a biologically friendly environment. Sequential logic is critical to detecting and visualising the biological micro-environment, which concerns both the previous and current states. However, the research to date has primarily focused only on combinational logic rather than sequential logic. Thus, this paper proposes novel sequential logic DNA circuits through the competition mechanism, allowing recognising previous and current triggering sequential signals. We report the sequential logical gates using DNAzymes and illustrate their potential applications. This work would be a valid building block in molecular computing to perform more complicated tasks in the biological microenvironment.