1. POSTER TEMPLATE BY: www.PosterPresentations.com Fabrication of Nanobiosensors Tom Fitzgerald, Nathan Howell, Brian Maloney Oregon State University, Department of Chemical, Biological, and Environmental Engineering Impact of Nanobiosensors Meet the Team Fabrication CharacterizationProtein Binding Accomplishments – Carbon Nanotube Growth OPTIONAL LOGO HERE Over 500,000 people die every year from cancer Early detection of cancer biomarkers will increase patient survival rate Early stage cancer biomarkers are present at 100 fM concentrations Figure below depicts survival rate according to the years after diagnosis and stage of cancer Project Components: Catalyst deposition and aligned CNT growth Photolithography Non-specific protein binding 5μm5μm -Growth using thermally evaporated iron catalyst -Growth using sputtered iron Basic Protein Detection: Bind entire nanotube surface with protein antibodies (green) Expose nanotube to solution containing the protein of interest Protein binding to antibodies will result in a detectable change of current through the nanotube Literature Results: Figure to the right represents current vs. time for different concentrations of streptavidin Higher concentrations of protein resulted in larger current Future Work t = 32 s t = 45 s t = 60 s 1 - Start with step cut quartz 2 – Using photolithography, create lines on quartz running perpendicular to steps 3 – Deposit catalyst on substrate 4 – Wash away photoresist, leaving lines of catalyst 5 – React with carbon gas in furnace to grow nanotubes 6 – Using evaporation, deposit chrome/gold electrodes and contact pads 7 – Mask nanotubes between electrodes, and O 2 plasma etch excess tubes and any debris 8 - Final Product Acknowledgements: - Dr. Milo Koretsky -Dr. Joe McGuire - Matt Leyden- Josh Kevek - Landon Prisbey-Shamon Walker - Canan Schuman-Eric Gunderson Dr. Phil Harding Linus Pauling Chair, Dept. of CBEE Dr. Ethan Minot Project Sponsor, Dept. of Physics Brian Maloney Team lead Protein adhesion Tom Fitzgerald Photolithography Nathan Howell Characterization An atomic force microscope is used to take “pictures’ at the nano-scale Continue investigation of catalyst deposition. -Sputter vs. evaporation Investigate metal catalyst. -Iron vs copper Complete first device before conclusion of project. Height (pm) 531531 1.2 1.0 0.6 0.2 321321 A flow cell is used to flow a small amount of current over the sensor. An AFM works by tapping a surface and measuring the changes in amplitude. When sputtering, an ion is propelled toward a metal target. This collision with the target releases metal atoms, which land on the substrate surface. Aligned CNTs!! White “specs” are iron catalyst particles CNTs grown on striped substrate. Short, dense, non-aligned tubes were grown. 0 1 2 3 4 µm 4321043210 0 1 2 3 4 5 µm 32103210 Cancerresearchuk.org Objective: Utilize aligned carbon nanotubes to construct a device capable of measuring changes in current while in solution Why Nano? Carbon nanotubes are an ideal semiconductor to detect small changes in current Surfaces of nanotubes provide a good area for protein adhesion 0 100 200 300 nm 0 100 200 300 nm 0 200 400 600 nm Comparison of nanotube growth at three different sputter times are shown below with AFM images and nanotube cross sections.