Metallointercalated-DNA Nanotubes as Functional Light Antenna for Organic Photoelectrochemical Transistor Biosensor with Minimum Background
Xiaodi Wu, Zheng Li, Jin Hu, Shumin Wang, Yichao Wang, Peng Lin, Hong Zhou, Weiwei Zhao
Abstract
Organic photoelectrochemical transistor (OPECT) biosensor with a removed background is desired but remains challenging. So far, scientists still lack a solution to this issue. The light-matter interplay is expected to achieve an advanced OPECT with unknown possibilities. Here, we address this challenge by tailoring a unique heterogeneous light antenna as the functional gating module and its cascade interaction with a proper channel, which is exemplified by bioinduced [Ru(bpy) 2 dppz] 2+ -intercalated DNA nanotubes (NTs)/NiO heterojunction and its modulation against a diethylenetriamine-treated poly(ethylene dioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) channel. Light stimulation of the antenna can generate the obvious cathodic photocurrent and, hence, modulate the channel, accomplishing OPECT with a minimal background and the hitherto highest current gain of 19 000. Linking with nucleic acid hybridization using microRNA-155 as the representative target, the device achieves sensitive biosensing down to 5.0 fM.