Communication-Cucurbituril Mediated Electronic Identification of Single Nucleobases

Electronically detecting and identifying four DNA nucleosides offers great opportunity in DNA sequencing. By introducing a cage-shaped molecule cucurbit[7]uril (CB[7]) into the tunneling junction to capture nucleobases, we show that all four DNA nucleobases can be better detected and identified, in contrast to the results measured with bare electrodes, and a conductivity order of T < A similar to C < G can be clearly revealed with a correct single base read up to 84% from each individual tunneling signal. This work provides a unique electronic approach in identifying single DNA bases and paves the way for the realization of high-precision DNA single-molecule analysis using tunneling current.