title: Suspended, micron-scale corner cube retroreflectors as ultra-bright optical labels.
abstract: Corner cube retroreflectors are objects with three mutually perpendicular reflective surfaces that return light directly to its source and are therefore extremely bright and easy to detect. In this work, we have fabricated suspended corner cube retroreflectors, 5 microns in size, consisting of a transparent epoxy core and three surfaces coated with gold as ultra-bright labels for use in a rapid, low-labor diagnostic platform. The authors have demonstrated that individual cubes are easily imaged using low-cost, low numerical aperture objectives in suspension and that they remain suspended over long periods of time. Moreover, we have demonstrated that the gold outer surfaces can be decorated with proteins, and that individual cubes can be bound to magnetic sample preparation particles bearing antibodies which recognize these proteins. The bound cubes can be imaged and tracked as they move through solution in response to an external magnetic field, and we have, as such, demonstrated the principle of the new biosensing approach.
authors.affiliation: Department of Electrical and Computer Engineering, University of Houston, Houston, Texas 77004.
authors.forename: Tim
authors.initials: T
authors.lastname: Sherlock
authors.affiliation: Department of Electrical and Computer Engineering, University of Houston, Houston, Texas 77004.
authors.forename: Azeem
authors.initials: A
authors.lastname: Nasrullah
authors.affiliation: Department of Biomedical Engineering, University of Houston, Houston, Texas 77004.
authors.forename: Julia
authors.initials: J
authors.lastname: Litvinov
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas 77004.
authors.forename: Eliedonna
authors.initials: E
authors.lastname: Cacao
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas 77004.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Knoop
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas 77004.
authors.forename: Steven
authors.initials: S
authors.lastname: Kemper
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas 77004.
authors.forename: Katerina
authors.initials: K
authors.lastname: Kourentzi
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas 77004.
authors.forename: Archana
authors.initials: A
authors.lastname: Kar
authors.affiliation: Department of Electrical and Computer Engineering and Department of Biomedical Engineering, University of Houston, Houston, Texas 77004.
authors.forename: Paul
authors.initials: P
authors.lastname: Ruchhoeft
authors.affiliation: Department of Chemical and Biomolecular Engineering and Department of Biology and Biochemistry, University of Houston, Houston, Texas 77004.
authors.forename: Richard
authors.initials: R
authors.lastname: Willson