Multi-Cantilevered Tetrahedral DNA Spider (TDSpider): An Efficient Molecular Machine for Biometrics and Disease Diagnosis

Low-dimensional machines frequently encounter difficulties in terms of limited walking efficiency, largely due to the scarcity of binding arms and inaccurate biorecognition process. Fabricating molecule machines possessing flexible effector that facilitates the conversion of target content into a signal, and entitle machines with stereoscopic structure, could largely enhance the operational efficiency of conventional molecule machines through recognition and transferring process. Here a multicantilevered TDN was synthesized, comprising extended arms with allosteric nucleic acid enzyme (ANAzyme), named "DNA spider" (TDSpider, TDS). In specific, upon introduction of the target, the extended arms bind with targets and fold to active ANAzyme, which serves as a highly sensitive regulator, thereby initiating the TDS. It crawls on the surface of nanomaterials in a more predictable and precise manner and exhibits bimodal operable property with liberating fluorescence signals on the surface of gold nanoparticles (AuNPs) orbitals and elemental signals on the surface of magnetic beads (MBs) orbitals. TDS demonstrates improved walking efficiency compared to 1D DNA machines and promises to provide novel tools for biometrics and disease diagnostic processes.