Sequence-specific molecular lithography towards DNA-templated electronics

Recent advances in the realization of individual molecular-scale devices [1,2] highlight the integration of individual devices into large-scale functional circuits as the major challenge. DNA-programmed assembly is a promising avenue in that direction due to the large amount of information that can be coded into the molecules and the ability to translate that information into physical constructs [3]. Large-scale DNA-templated electronics require, however, complex manipulation of double-stranded DNA (dsDNA) molecules, as well as patterning of the electrical properties instilled to them by, e.g., metallization. To that end, sequence-specific molecular lithography on single DNA molecules has been developed [4]. This was achieved by harnessing the exquisite homologous recombination process of the RecA protein. Sequence-specific patterning of the metal coating of DNA molecules, localization of arbitrary labeled molecular objects at any desired dsDNA address without prior modifications, and generation of molecularly accurate stable dsDNA-dsDNA junctions are demonstrated. The information encoded in the DNA molecules directs the lithographic process in analogy to the masks used in conventional microelectronics. The RecA protein provides the assembling capabilities, as well as the resist function.