| abstract |
A device (10) for determining an analyte in a fluid sample consists essentially of a dimensionally stable, uniformly porous, diffusely reflective single layer (20) formed of a polymeric non-fibrous matrix and, dispersed throughout said matrix, at least one substance which effects a detectable response to the analyte. Preferably, the polymer is a high density polyethylene treated to be hydrophilic. The optical properties of the device can be further modified by blending in pigments, such as titanium dioxide. The analyte-responsive substance can include a first component which is responsive to the analyte to form a reaction product and a second component separated from the first component binder and responsive to the reaction product to effect a detectable change. The device is completely effective in the absence of other elements or structures to provide a quantitative detectable response to the presence of the analyte under assay. |