| abstract |
A multilayer analytical element for detecting a ligand in or the ligand binding capacity of a liquid sample of the type having a reagent layer(s) incorporating reagents which are responsive to the ligand in or the ligand binding capacity of the sample to give a detectable response, a radiation reflecting layer, and a support layer, the improvement wherein the reagent layer(s) is a radiation diffusing layer and the radiation reflecting layer is a radiation nondiffusing reflecting layer which is (a) interposed between the reagent layer(s) and the support layer; (b) impermeable to the ligand, reagents of the reagent layer(s), and products of their interreaction; and (c) inert to the ligand, reagents of the reagent layer(s), and products of their interreaction. |