Design of an artificial functional nanomaterial with high recognition ability

Abstract

An artificial macromolecule was designed as a novel nanomaterial with the backbone of phosphodiester and the side chain of functional molecules and nucleobases. The functional molecules tethered on d-threoninol and the nucleosides on d-ribose can be lined up with any sequence and any ratio by using standard phosphoramidite chemistry. The nucleobases that form Watson---Crick base pairs provide the sequence recognition which is required for constructing complicate nanostructures. The multiple functional molecules give applicable and advanced functions such as photoresponsiveness when azobenzenes were used. Unexpectedly, a stable double helix was formed even in the case that the ratio of azobenzene molecules and base pairs was as high as 2:1. More interestingly, this artificial duplex showed high sequence specificity: the stability decreased greatly when a mismatched base pair was present. Furthermore, the formation and dissociation of the constructed artificial duplex were reversibly and completely modulated with light irradiation. By using this new nanomaterial, a variety of functional nanostructures and nanodevices are promising to be designed. The possibility of our system being used for DNA computing is also discussed.