Patterned Binding of Functionalized Microspheres for Optical Diffraction-based Biosensors

PATTERNED BINDING OF FUNCTIONALIZED MICROSPHERES FOR OPTICAL DIFFRACTION-BASED BIOSENSORS Abstract The present invention provides an inexpensive and sensitive system and method for 5 detecting analytes present in a medium. The system comprises a diffraction enhancing element, such as functionalized microspheres, which are modified such that they are capable of binding with a target analyte. Additionally, the system comprises a polymer film, which may include a metal coating, upon which is printed a specific, pre-determined pattern of analyte-specific receptors. Upon attachment of a target analyte to select areas 10 of the polymer film, either directly or with the diffraction enhancing element, diffraction of transmitted and/or reflected light occurs via the physical dimensions and defined, precise placement of the analyte. A diffraction image is produced which can easily seen with the eye or ,optionally, with a sensing device.