Upconversion-chameleon-driven DNA computing: the DNA-unlocked inner-filter-effect (DU-IFE) for operating a multicolor upconversion luminescent DNA logic library and Its biosensing application

Abstract

DNA computing has shown impressive developments and exhibited amazing power over the past few decades. However, most current DNA logic devices can only produce single-modal output that is monochromic or even invisible, which greatly limits their reliability and practicality, integration capability and computing complexity. Emission-tunable upconversion nanoparticles (UCNPs) are ideal multicolor outputs for DNA computing, however UC luminescent (UCL) DNA logic systems have rarely been reported. Here, for the first time, we report “DNA-Unlocked Inner-Filter-Effect” (DU-IFE) between oxidized 3,3′,5,5′-tetramethylbenzidine (OxTMB) and upconversion nanoparticles (UCNPs) that subtly matches a “lock–key” strategy. Based on the DU-IFE, we construct the first ever UCL DNA logic library. Superior to previous DNA logic systems, this logic library can generate dual-modal (visual and UCL) multicolor label-free outputs, in which RGB (red, green, blue) colorful UCL ones are also visual under harmless NIR-laser. By selectively unlocking the IFE “lock” with different DNA “keys”, diverse basic, advanced and concatenated logic circuits, a logic-controlled molecular RGB-signal-light, triple-parallel-arrays are successfully constructed. All of the above logic operations demonstrate the strengthened reliability and practicality, powerful integration capability and improved computing complexity of this UCL logic library. Moreover, we fabricate an inspiring and useful biosensor with RGB colorful results based on the DU-IFE (a DNA caliper), providing a vivid prototype for potential biological applications.