Design and fabrication of a multianalyte-capable optical biosensor using a multiphysics approach

An evanescent-wave biosensor was designed and fabricated using simple and robust microfabrication technology. The significance of the sensor is the design method, in which a multiphysical approach is used to draw from much broader field than is customary for these sensor types. The sensor uses a microscale NOA61 optical waveguide that is surface-altered with a custom chemical modification process, coupled with modified self-assembly of a fluorescent dye and enzyme. To interface the analyte with the waveguide surface, a multilayer PDMS fluidic mold is designed to fit over the waveguide. Interfacing of both optics and fluidics are achieved using specifically-designed couplings. The entire device has been successfully fabricated and assembled, with preliminary analyte response testing completed.