Gated Single-Molecule Transport in Double-Barreled Nanopores

Abstract

Single-molecule methods have been rapidly developing with the appealing prospect of transforming conventional ensemble-averaged analytical techniques. However, challenges remain especially in improving detection sensitivity and controlling molecular transport. In this article, we present a direct method for the fabrication of analytical sensors that combine the advantages of nanopores and field-effect transistors for simultaneous label-free single-molecule detection and manipulation. We show that these hybrid sensors have perfectly aligned nanopores and field-effect transistor components making it possible to detect molecular events with up to near 100% synchronization. Furthermore, we show that the transport across the nanopore can be voltage-gated to switch on/off translocations in real time. Finally, surface functionalization of the gate electrode can also be used to fine tune transport properties enabling more active control over the translocation velocity and capture rates.

Surface coatings for solid-state nanopores

“…We hope that this overview will be helpful for solving or minimizing some of the problems that hamper the usefulness of nanopore-based analytics of complex, real world samples. 275 We predict that the nanopore field will continue to expand the strategies for increasing the functionality of nanopores 300 and nanocapillaries [301][302][303] and that coatings will play an essential role in this development. We expect to witness an increase, both in the number of ways how coatings will be applied, and in the fine-tuning of their molecular composition.…”

Selective Sensing of Proteins Using Aptamer Functionalized Nanopore Extended Field‐Effect Transistors

“…Precise control of the nanopore dimension can be achieved by the real‐time feedback, by monitoring the I DS (Figure 2c) similar to previous reports. [ 32,33 ] By using this controllable fabrication process, the deposition could be stopped at a defined threshold of the current passing through the nanopore I DS . The process is reproducible and results in PPy‐coated nexFET with very similar ionic I – V characteristics (Figure 2g).…”

“…Our group has also developed nanopore designs coupled with ionic-FETs, where a gate voltage was used to facilitate molecular transport at the single-molecule level. [32,33] In one of these designs, a nanopore extended FET (nexFET) was functionalized with a polypyrrole (PPy) layer that incorporated protein receptors. By applying the gate voltage our group has demonstrated that molecular transport can be efficiently controlled at the single-molecule level.…”

“…Our group has also developed nanopore designs coupled with ionic‐FETs, where a gate voltage was used to facilitate molecular transport at the single‐molecule level. [ 32,33 ]…”

Needle-type organic electrochemical transistor for spatially resolved detection of dopamine

“…The device was used to detect single-molecule translocation events of DNA and, with insulin-modified PPy, IgG antibodies [37]. Moreover, the use of a Au gate-equipped nanopore−FET has been demonstrated to allow the synchronised detection of single molecule events in both nanopore and gate channels [38]. With a different approach, nanometric FET sensors were obtained on the tip of spear-shaped dual-carbon nanoelectrodes by electrodeposition of a PPy channel.…”