Abstract: A method for the detection of a predetermined substance in a fluid is described. The method uses a test strip that is stable to storage and accelerated keeping test conditions. A sample of a fluid containing an unknown quantity of a predetermined substance is contacted with a support having thereon a reagent layer wherein the reagent layer contains a dialyzed latex polymer and a reagent detection system which reacts with the substance to provide a detectable change. The detectable change can be determined qualitatively or quantitatively to determine the presence or the amount of the predetermined substance.

Abstract: A diagnostic test strip for the detection of a analyte in a test fluid. The test strip has a reagent layer on a support layer. The reagent layer contains an analyte detection system in a non-particulate dialyzed latex polymer.