Patent ID: 7244393

Claim:
A diffraction-based assay device for detecting the presence of an analyte, the device comprising: a substrate that comprises a polymer film, wherein a first binder is present on the substrate in a pattern; a fluidic guide with a first end and a second end in direct communication with a wicking agent, wherein the first end of the fluidic guide defines an opening therein for sample application and includes at least one channel through which a fluid test sample is capable of flowing via capillary action to the second end, wherein the wicking agent is capable of receiving the fluid test sample from the second end of the fluidic guide and thereafter facilitating contact of the fluid sample with the binder on the substrate; and an electromagnetic radiation source that is configured to direct electromagnetic radiation to the substrate through the first end of the fluidic guide to the opening to generate a diffraction pattern proximate an area of the substrate defined by the second end of the guide.