title: Photonic-crystal membranes for optical detection of single nano-particles, designed for biosensor application.
abstract: A sensor designed to detect bio-molecules is presented. The sensor exploits a planar 2D photonic crystal (PC) membrane with sub-micron thickness and through holes, to induce high optical fields that allow detection of nano-particles smaller than the diffraction limit of an optical microscope. We report on our design and fabrication of a PC membrane with a nano-particle trapped inside. We have also designed and built an imaging system where an optical microscope and a CCD camera are used to take images of the PC membrane. Results show how the trapped nano-particle appears as a bright spot in the image. In a first experimental realization of the imaging system, single particles with a radius of 75 nm can be detected.
authors.affiliation: Department of Electronics and Telecommunications, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway. jonolav.grepstad@sintef.no
authors.forename: Jon Olav
authors.initials: JO
authors.lastname: Grepstad
authors.forename: Peter
authors.initials: P
authors.lastname: Kaspar
authors.forename: Olav
authors.initials: O
authors.lastname: Solgaard
authors.forename: Ib-Rune
authors.initials: IR
authors.lastname: Johansen
authors.forename: Aasmund S
authors.initials: AS
authors.lastname: Sudbø
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D003460:Crystallization; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008567:Membranes, Artificial; D057054:Molecular Imaging / Q000295:instrumentation*; D015336:Molecular Probe Techniques / Q000295:instrumentation*; D053758:Nanoparticles / Q000032:analysis*; D055096:Optical Devices; D017785:Photons
chemical_list: D008567:Membranes, Artificial