Automated Target-Driven Molecular Machine-Based Engineering Process For SARS-CoV-2 Monitoring

Nucleic acid structured electrochemiluminescence (ECL) biosensors provide valuable, versatile, programmable support for the development of medical diagnostics. Here, we constructed an automated DNA molecular machine with just one thiol-modified DNA probe and three nucleic acid probes on the surface of Ti3C2-based composites to monitor SARS-CoV-2, free from the limitations of motion tracks on the DNA molecular machine and significantly decreasing the probe modification fee. In the presence of the target, the designed DNA molecular machine conducted a modular reaction to transduce the target concentration information into an enhancement of the ECL signal based on DNA hybridization calculations. Modular, scalable reactions occur on DNA automata, reducing complex bioanalytical reactions to a single nucleic acid probe unit and eliminating the tedious steps of laying down motion tracks required by traditional molecular machines. By designing three capture probes, it is possible to extend the application ranges of the protocol from single to multi-target monitoring. Moreover, the strategy implements the bioanalysis of the SARS-CoV-2 in complex environments such as saliva dilutions and serum dilutions, which is valuable in promoting public health development and evaluating the environmental hazards of SARS-CoV-2.