title: Implementing Silicon Nanoribbon Field-Effect Transistors as Arrays for Multiple Ion Detection.
abstract: Ionic gradients play a crucial role in the physiology of the human body, ranging from metabolism in cells to muscle contractions or brain activities. To monitor these ions, inexpensive, label-free chemical sensing devices are needed. Field-effect transistors (FETs) based on silicon (Si) nanowires or nanoribbons (NRs) have a great potential as future biochemical sensors as they allow for the integration in microscopic devices at low production costs. Integrating NRs in dense arrays on a single chip expands the field of applications to implantable electrodes or multifunctional chemical sensing platforms. Ideally, such a platform is capable of detecting numerous species in a complex analyte. Here, we demonstrate the basis for simultaneous sodium and fluoride ion detection with a single sensor chip consisting of arrays of gold-coated SiNR FETs. A microfluidic system with individual channels allows modifying the NR surfaces with self-assembled monolayers of two types of ion receptors sensitive to sodium and fluoride ions. The functionalization procedure results in a differential setup having active fluoride- and sodium-sensitive NRs together with bare gold control NRs on the same chip. Comparing functionalized NRs with control NRs allows the compensation of non-specific contributions from changes in the background electrolyte concentration and reveals the response to the targeted species.
authors.affiliation: Department of Physics, University of Basel, Basel 4056, Switzerland. ralph.stoop@unibas.ch.
authors.forename: Ralph L
authors.initials: RL
authors.lastname: Stoop
authors.affiliation: Department of Physics, University of Basel, Basel 4056, Switzerland. mathias.wipf@gmail.com.
authors.forename: Mathias
authors.initials: M
authors.lastname: Wipf
authors.affiliation: Department of Chemistry, University of Basel, Basel 4056, Switzerland. muelst@gmx.de.
authors.forename: Steffen
authors.initials: S
authors.lastname: Müller
authors.affiliation: Laboratory for Micro- and Nanotechnology, Paul Scherrer Institute, Villigen 5232, Switzerland. KristineBedner@gmx.net.
authors.forename: Kristine
authors.initials: K
authors.lastname: Bedner
authors.affiliation: Department of Chemistry, University of Basel, Basel 4056, Switzerland. iain.wright@durham.ac.uk.
authors.forename: Iain A
authors.initials: IA
authors.lastname: Wright
authors.affiliation: Department of Chemistry, University of Basel, Basel 4056, Switzerland. colinmtn@gmail.com.
authors.forename: Colin J
authors.initials: CJ
authors.lastname: Martin
authors.affiliation: Department of Chemistry, University of Basel, Basel 4056, Switzerland. edwin.constable@unibas.ch.
authors.forename: Edwin C
authors.initials: EC
authors.lastname: Constable
authors.affiliation: Department of Physics, University of Basel, Basel 4056, Switzerland. axel.fanget@unibas.ch.
authors.forename: Axel
authors.initials: A
authors.lastname: Fanget
authors.affiliation: Department of Physics, University of Basel, Basel 4056, Switzerland. Christian.Schoenenberger@unibas.ch.|Swiss Nanoscience Institute, University of Basel, Basel 4056, Switzerland. Christian.Schoenenberger@unibas.ch.
authors.forename: Christian
authors.initials: C
authors.lastname: Schönenberger
authors.affiliation: Department of Physics, University of Basel, Basel 4056, Switzerland. michel.calame@unibas.ch.|Swiss Nanoscience Institute, University of Basel, Basel 4056, Switzerland. michel.calame@unibas.ch.
authors.forename: Michel
authors.initials: M
authors.lastname: Calame
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation; D007477:Ions / Q000737:chemistry; D053770:Nanowires / Q000737:chemistry; D012825:Silicon / Q000737:chemistry; D014173:Transistors, Electronic
chemical_list: D007477:Ions; D012825:Silicon
keywords: chemFETs; chemical sensing; fluoride; gold; ion-sensitive field-effect transistors; nanoribbons; sodium