title: Wide-field optical detection of nanoparticles using on-chip microscopy and self-assembled nanolenses.
abstract: The direct observation of nanoscale objects is a challenging task for optical microscopy because the scattering from an individual nanoparticle is typically weak at optical wavelengths. Electron microscopy therefore remains one of the gold standard visualization methods for nanoparticles, despite its high cost, limited throughput and restricted field-of-view. Here, we describe a high-throughput, on-chip detection scheme that uses biocompatible wetting films to self-assemble aspheric liquid nanolenses around individual nanoparticles to enhance the contrast between the scattered and background light. We model the effect of the nanolens as a spatial phase mask centred on the particle and show that the holographic diffraction pattern of this effective phase mask allows detection of sub-100 nm particles across a large field-of-view of >20 mm2. As a proof-of-concept demonstration, we report on-chip detection of individual polystyrene nanoparticles, adenoviruses and influenza A (H1N1) viral particles.
authors.affiliation: Electrical Engineering Department, University of California, Los Angeles, California 90095, USA ; Bioengineering Department, University of California, Los Angeles, California 90095, USA.
authors.forename: Onur
authors.initials: O
authors.lastname: Mudanyali
authors.affiliation: Electrical Engineering Department, University of California, Los Angeles, California 90095, USA ; Bioengineering Department, University of California, Los Angeles, California 90095, USA.
authors.forename: Euan
authors.initials: E
authors.lastname: McLeod
authors.affiliation: Electrical Engineering Department, University of California, Los Angeles, California 90095, USA ; Bioengineering Department, University of California, Los Angeles, California 90095, USA.
authors.forename: Wei
authors.initials: W
authors.lastname: Luo
authors.affiliation: Electrical Engineering Department, University of California, Los Angeles, California 90095, USA ; Bioengineering Department, University of California, Los Angeles, California 90095, USA.
authors.forename: Alon
authors.initials: A
authors.lastname: Greenbaum
authors.affiliation: Electrical Engineering Department, University of California, Los Angeles, California 90095, USA ; Bioengineering Department, University of California, Los Angeles, California 90095, USA.
authors.forename: Ahmet F
authors.initials: AF
authors.lastname: Coskun
authors.affiliation: CEA, LETI, MINATEC, 17 rue des Martyrs, 38054 Grenoble cedex 9, France.
authors.forename: Yves
authors.initials: Y
authors.lastname: Hennequin
authors.affiliation: CEA, LETI, MINATEC, 17 rue des Martyrs, 38054 Grenoble cedex 9, France.
authors.forename: Cédric P
authors.initials: CP
authors.lastname: Allier
authors.affiliation: Electrical Engineering Department, University of California, Los Angeles, California 90095, USA ; Bioengineering Department, University of California, Los Angeles, California 90095, USA ; California NanoSystems Institute, University of California, Los Angeles, California 90095, USA ; Department of Surgery, David Geffen School of Medicine, University of California, Los Angeles, California 90095, USA.
authors.forename: Aydogan
authors.initials: A
authors.lastname: Ozcan