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A novel and versatile biosensing platform based on the structural conversion of 3D DNA nanostructures from ETDNA (Equilateral Triangle) to TPFDNA (Triangular Pyramid Frustum) was proposed for the first time. The inputs of aptamers and their relative targets made the DNA structure change from the "Open" to the "Closed" state, leading to the faradaic impedance changes as the output signals. The specific properties of excellent stability and specific rigid structure of 3D DNA nanostructures made the biosensor function as a regenerable, reusable and intelligent platform. The sensor exhibited excellent selectivity for IFN-γ detection with a wide linear range of 1.0 × 10(-9) to 2.0 × 10(-6) M and a low detection limit of 5.2 × 10(-10) M. The distinctive features of DNA nanostructures make them potentially advantageous for a broad range of biosensing, bionanoelectronics, and therapeutic applications.

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A novel complex material was fabricated by three steps. In the first step, gold nanoparticle (Aunano) was prepared with the method of chemistry and dialysis. In the second step, 4‐aminothiophenol (AT) was encapsulated in the cavity of β‐cyclodextrin and formed inclusion complex, cyclodextrin/4‐aminothiophenol (CD/AT). And then inclusion complex was adsorbed to the surface of Aunano based on the bond of Au‐S interaction. In the last step, a complex material, cyclodextrin/poly(4‐aminothiophenol)‐Au nanoparticles (CD/PAT‐Aunano) was obtained by the polymerizing in the acid solution initiated by chlorauric acid. The CD/PAT‐Aunano has spherical nanostructure with the average diameter of 55 nm. Glucose oxidase (GOx) was anchored with this complex material and direct electrochemistry of GOx was achieved. A couple of stable and well‐defined redox peaks were observed with the formal potential (E0′) of ‐0.488 V (vs. SCE) in a pH 6.98 buffer solution. The GOx modified electrode also exhibited an excellent electrocatalytic activity to the reduction of glucose, a linearity range for determination of glucose is from 0.25 mM to 16.0 mM with a detection limit of 0.09 mM (S/N = 3). This protocol had potential application to fabricate the third‐generation biosensor.