Extended Data Fig. 5: Robustness of reusability.
From: Heat-rechargeable computation in DNA logic circuits and neural networks
a-d, Fluorescence kinetics experiments of a reusable catalytic DNA circuit with 100 rounds of reset using two distinct protocols that heat for 2 minutes (a,b) or 5 minutes (c,d) at 95 °C before cooling to 25 °C in 1 minute. Experiments were performed on a quantitative PCR machine and a single sample was used for all data shown in (a,b) and (c,d), respectively. Standard concentration 1× = 100 nM. The performance of the DNA circuit remained roughly the same for the first 10 rounds of reset (a). However, the output concentration decreased by 9, 29.3, and 27.5 nM for 1×, 0.2×, and 0.1× input, respectively, and increased by 12.3 nM for 0× input after 100 rounds of reset (b). Increasing the time at 95 °C from 2 to 5 minutes resulted in worse reset performance: a similar level of decrease in signal amplification with 0.1× to 1× input and increase in reset baseline with 0× input were observed after 40 rounds of reset (c). The total time at 95 °C for 100 rounds in (b) is the same as that for 40 rounds in (c). This observation suggested that DNA degradation at high temperature played a major role in the robustness of the reusability. The reset performance continued to worsen with longer total time at 95 °C: after 100 rounds of reset using the protocol that heats for 5 minutes, the output concentration for 0× input became indistinguishable from that for 0.1× input, reaching roughly half the output concentration for 1× input. Predictably, the output concentration would no longer change with input after 1,000 minutes of heating at 95 °C. This limits the maximum number of reset to on the order of 1,000 rounds if a protocol with 1-minute heating is applied.
