Reversible Logic Gates Based on Enzyme‐Biocatalyzed Reactions and Realized in Flow Cells: A Modular Approach

Abstract

Reversible logic gates, such as the double Feynman gate, Toffoli gate and Peres gate, with 3‐input/3‐output channels are realized using reactions biocatalyzed with enzymes and performed in flow systems. The flow devices are constructed using a modular approach, where each flow cell is modified with one enzyme that biocatalyzes one chemical reaction. The multi‐step processes mimicking the reversible logic gates are organized by combining the biocatalytic cells in different networks. This work emphasizes logical but not physical reversibility of the constructed systems. Their advantages and disadvantages are discussed and potential use in biosensing systems, rather than in computing devices, is suggested.

Bioelectronic Interface Connecting Reversible Logic Gates Based on Enzyme and DNA Reactions

“…The adsorbed PEI was then sequentially reacted with glutaric dialdehyde and enzymes. [36,37] Optical absorbance measurements were performed for the control channel (output P)a tl max = 415 nm, characteristic of ABTS ox ,a nd for the data channels (outputs Q and R)a tl max = 340 nm, following the biocatalytic production of NADH. The input concentrations were experimentally optimized for the specific enzyme activity in the flow cells.…”

“…This approach resulted in the design of complex logically reversible computing systems. [36,37] In brief, logic reversibility is particularly important for biosensing applications of biomolecular logic systemsb yp roviding information about the whole set of analytical input signals. Interested readers can find an extensive discussion on logic reversibility (which does not mean physical reversibility) in our recently publishedp apers specifically addressing this issue for biomolecular computing systems.…”

Controlled Logic Gates—Switch Gate and Fredkin Gate Based on Enzyme‐Biocatalyzed Reactions Realized in Flow Cells

“…Sophisticated molecular design has permitted reconfigurable and resettable logic gates for chemical information processing. Molecular and biomolecular systems mimicking operation of reversible logic gates, such as Toffoli, Fredkin, Peres and Feynman gates, represent particular interest for unconventional computing due to their unique logic properties. Their operations are called “ logically reversible ” because each combination of logic input signals can be derived from the obtained output signals, thus processing input signals without loss of information .…”

“…It should be noted that the chemical realization of reversible logic gates does not allow their “ physical reversibility ” since the used chemical reactions usually cannot operate in the opposite direction. This results in the absence of energy savings upon the operation of chemical “ logically reversible ” gates due to inevitable energy dissipation in the course of chemical reactions . While energy saving physically reversible computing processes, theoretically predicted and experimentally realized in some electronic systems, are considered as highly important for future progress in electronic computing, chemical systems performing logically reversible operations without physical reversibility could be important for sensing/biosensing processes.…”

“…They obviously do not pretend to operate as energy saving systems and discussions on the energy saving properties published in some papers related to chemical/biochemical unconventional computing originate from misunderstanding of the difference between chemical and electronic systems. Extensive discussion on the motivation for studying biomolecular reversible logic systems and their potential applications was published recently in our paper devoted to the enzyme‐based Toffoli, Peres and Double Feynman gates …”