title: Ultrasensitive detection of cytokines enabled by nanoscale ZnO arrays.
abstract: Early detection of disease markers can provide higher diagnostic power and improve disease prognosis. We demonstrate the use of zinc oxide nanorod (ZnO NR) arrays in a straightforward, reliable, and ultrasensitive detection of the cytokines interleukin-18 and tumor necrosis factor-alpha. Specifically, we exploit the fluorescence-enhancing properties of ZnO NR platforms in cytokine assays involving both a pure buffer and urine. The detection sensitivity achieved using this ZnO NR method is in the subfemtogram per milliliter level, which is 3-4 orders of magnitude more sensitive than conventional assay detection limits. This unparalleled detection sensitivity is achieved without the need for indirect enzyme reactions or specialized instrumentation. We highlight various advantages of using ZnO NR arrays in the ultrasensitive profiling of cytokine levels. Key advantages include robustness of NR arrays, simple and direct assay schemes, high-throughput and multiplexing capabilities, and the ability to correlate directly measured signals to cytokine levels. In conjunction with the extremely high sensitivity demonstrated in this work, our ZnO NR array-based approach may be highly beneficial in early detection of many cytokine-implicated diseases.
authors.affiliation: Department of Chemical Engineering, The Pennsylvania State University, 160 Fenske Laboratory, University Park, Pennsylvania 16802, USA.
authors.forename: Viktor
authors.initials: V
authors.lastname: Adalsteinsson
authors.forename: Omkar
authors.initials: O
authors.lastname: Parajuli
authors.forename: Stephen
authors.initials: S
authors.lastname: Kepics
authors.forename: Abhishek
authors.initials: A
authors.lastname: Gupta
authors.forename: W Brian
authors.initials: WB
authors.lastname: Reeves
authors.forename: Jong-in
authors.initials: JI
authors.lastname: Hahm
mesh_terms: D000818:Animals; D002417:Cattle; D016207:Cytokines / Q000032:analysis* / Q000652:urine*; D006801:Humans; D020382:Interleukin-18 / Q000032:analysis / Q000652:urine; D046228:Microarray Analysis / Q000379:methods*; D043942:Nanotubes / Q000737:chemistry*; D012680:Sensitivity and Specificity; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis / Q000652:urine; D015034:Zinc Oxide / Q000737:chemistry*
chemical_list: D016207:Cytokines; D020382:Interleukin-18; D014409:Tumor Necrosis Factor-alpha; D015034:Zinc Oxide