Ionic nanoarchitectonics for nanochannel-based biosensing devices

TOUM TERRONES, YAMILI; LAUCIRICA, GREGORIO; CAYÓN, VANINA; CORTEZ, M. LORENA; MARÍA EUGENIA TOIMIL-MOLARES; CHRISTINA TRAUTMANN; MARMISOLLÉ, WALDEMAR; AZZARONI, OMAR

Materials Nanoarchitectonics. From integrated molecular systems to advanced devices

Elsevier

Año: 2023; p. 429 - 452

Biological ion channels can be defined as ion-transport proteins located in cell membranes.Through them, the cell is capable of transporting ions across the membrane which is crucial formany vital life processes such as pumping nutrients into cells, generating electrical signals, and reg-ulating cell volume [1]. Although a vast variety of ion channels with different structures and func-tions is known, they all share one fundamental property: a notorious ability to transport ions in aselective mode [1]. The potassium ion channel is a paradigmatic example: its potassium transportrate is near the diffusion limit without leaving selectivity aside [2]. In the last decades, inspired bythe outstanding properties of biological ion channels, many research groups decided to focus theirattention on the development of fully abiotic solid-state nanopores and nanochannels for (bio)sens-ing, energy conversion, filtration, nanoelectronics, and other applications [3,4]. Synthetic solid-statenanochannels (SSNs) (length much larger than diameter) and nanopores (SSNPs) (length and diam-eter with similar dimensions) can be designed to meet not only key properties that characterizebiological ion channels such as selectivity, stimulus responsiveness, and ion rectification but also tobe chemically versatile, highly robust, and mechanically resistant [5,6]. Over recent decades, mate-rial science and nanofabrication techniques are moving ahead at a staggering speed enabling theconstruction of nanopores and nanochannels with dimensions comparable to the size of biologicalmolecules that not only can be used as stimuli-responsive nanofluidic elements [716], but also asremarkably sensitive molecule biosensors [17]. As the biosensing performance of these nanofluidicdevices is strongly linked to the surface characteristics of their inner walls, much effort has beenmade to establish surface-modification strategies at the nanoscale level [4].