title: ImmunoFET feasibility in physiological salt environments.
abstract: Field-effect transistors (FETs) are solid-state electrical devices featuring current sources, current drains and semiconductor channels through which charge carriers migrate. FETs can be inexpensive, detect analyte without label, exhibit exponential responses to surface potential changes mediated by analyte binding, require limited sample preparation and operate in real time. ImmunoFETs for protein sensing deploy bioaffinity elements on their channels (antibodies), analyte binding to which modulates immunoFET electrical properties. Historically, immunoFETs were assessed infeasible owing to ion shielding in physiological environments. We demonstrate reliable immunoFET sensing of chemokines by relatively ion-impermeable III-nitride immunoHFETs (heterojunction FETs) in physiological buffers. Data show that the specificity of detection follows the specificity of the antibodies used as receptors, allowing us to discriminate between individual highly related protein species (human and murine CXCL9) as well as mixed samples of analytes (native and biotinylated CXCL9). These capabilities demonstrate that immunoHFETs can be feasible, contrary to classical FET-sensing assessment. FET protein sensors may lead to point-of-care diagnostics that are faster and cheaper than immunoassay in clinical, biotechnological and environmental applications.
authors.affiliation: Department of Biomedical Engineering, The Ohio State University, Columbus, 43210, USA.
authors.forename: Patricia
authors.initials: P
authors.lastname: Casal
authors.forename: Xuejin
authors.initials: X
authors.lastname: Wen
authors.forename: Samit
authors.initials: S
authors.lastname: Gupta
authors.forename: Theodore
authors.initials: T
authors.lastname: Nicholson
authors.forename: Yuji
authors.initials: Y
authors.lastname: Wang
authors.forename: Andrew
authors.initials: A
authors.lastname: Theiss
authors.forename: Bharat
authors.initials: B
authors.lastname: Bhushan
authors.forename: Leonard
authors.initials: L
authors.lastname: Brillson
authors.forename: Wu
authors.initials: W
authors.lastname: Lu
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Lee
mesh_terms: D000818:Animals; D000918:Antibody Specificity; D054370:Chemokine CXCL9 / Q000276:immunology; D005240:Feasibility Studies; D006801:Humans; D051379:Mice; D012666:Semiconductors
chemical_list: D054370:Chemokine CXCL9