title: Effects of buffer composition and dilution on nanowire field-effect biosensors.
abstract: Nanowire-based field-effect transistors (FETs) can be used as ultra-sensitive and label-free biosensors for detecting protein-protein interactions. A way to increase the performance of such sensors is to dilute the sensing buffer drastically. However, we show here that this can have an important effect on the function of the proteins. Moreover, it is demonstrated that this dilution significantly affects the pH stability of the sensing buffer, which consequently impacts the charge of the protein and thus the response and signal-to-noise ratio in the sensing experiments. Three model systems are investigated experimentally to illustrate the impact on ligand-protein and protein-protein interactions. Simulations are performed to illustrate the effect on the performance of the sensors. Combining various parameters, the current study provides a means for evaluating and selecting the most appropriate buffer composition for bioFET measurements.
authors.affiliation: Bio-Nanotechnology and Nanomedicine Laboratory, Department of Chemistry & Nano-Science Center, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Noémie
authors.initials: N
authors.lastname: Lloret
authors.forename: Rune S
authors.initials: RS
authors.lastname: Frederiksen
authors.forename: Thor C
authors.initials: TC
authors.lastname: Møller
authors.forename: Nathalie I
authors.initials: NI
authors.lastname: Rieben
authors.forename: Shivendra
authors.initials: S
authors.lastname: Upadhyay
authors.forename: Luca
authors.initials: L
authors.lastname: De Vico
authors.forename: Jan H
authors.initials: JH
authors.lastname: Jensen
authors.forename: Jesper
authors.initials: J
authors.lastname: Nygård
authors.forename: Karen L
authors.initials: KL
authors.lastname: Martinez
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D002021:Buffers; D006863:Hydrogen-Ion Concentration; D008958:Models, Molecular; D053770:Nanowires / Q000737:chemistry; D011485:Protein Binding; D025941:Protein Interaction Mapping / Q000295:instrumentation*; D011506:Proteins / Q000378:metabolism; D014173:Transistors, Electronic
chemical_list: D002021:Buffers; D011506:Proteins