A molecular robot is an important type of artificial molecular machine that automatically carry out nanomechanical tasks. DNA is an excellent material for building molecular robots, because their geometric, thermodynamic and kinetic properties are well understood and highly programmable. There exist no systematic approaches for translating high-level mechanical tasks to low-level molecular implementations nor software tools that enable researchers with diverse backgrounds to build DNA robots with new functions. To accomplish that, more simple algorithms and more modular building blocks are needed to create a wider range of collective behaviors, until there is enough understanding for the development of a molecular robotics programming language that will work in practice. This project will provide better answers to the following questions: To what extent can simple algorithms allow increasingly complex nanomechanical tasks to be programmed and carried out by DNA molecules? Does cooperation in DNA robots allow more complex tasks to be accomplished with less time and less energy? What composability issues arise when new building blocks are added to the toolbox for general-purpose DNA robots? What design principles can allow DNA robots to function well in increasingly complex and diverse operating environments? The scientific understanding will be incorporate into public online software tools to assist the design and construction of molecular robots, which will be introduced into the classroom. Course materials will be shared among multiple educational institutions. Public engagement will be promoted through public talks, lab tours, podcasts, news stories, YouTube videos and artwork.
The project involves three main goals: developing a new building block for leaving pheromone-like signals to mark where a robot has been, demonstrating how the new building block can be used to construct DNA robots that find and modify a direct path from the entrance to the exit in an arbitrary maze, and developing software tools that automatically convert user-specified robotics systems to design diagrams, simulations, DNA sequences and experimental protocols. DNA origami technique will be used to build testing grounds for DNA robots, while DNA strand displacement mechanism will be used to program the behavior of DNA robots. Fluorescence spectroscopy and atomic force microscopy will be used to quantitatively analyze the behavior of DNA robots, in bulk and at the single-molecule level. The team of investigators will study the mechanisms for tuning the behavior of DNA robots, if it is qualitatively but not quantitatively as designed, and understand how the behavior of DNA robots depends on the specific configuration of their operating environment. The new building block expands the toolbox for general-purpose DNA robots and allows tasks that involve surveying and marking an unknown environment. The maze-solving robots could be used to perform efficient molecular transportation where a group of leader robots mark a direct path in a complex environment using very little energy and a group of follower robots walk on marked path only to transport molecular cargos without spending any time on indirect routes.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
