Abstract: A test device and method of determining the presence and concentration of proteins, including albumin and Bence Jones proteins, in a test sample are disclosed. The test device includes a test pad comprising a new and improved carrier matrix incorporating an indicator reagent composition capable of interacting with proteins to produce a visually or instrumentally detectable and/or measurable response. The new and improved carrier matrix of the test pad comprises a fibrous, bibulous substrate, such as filter paper, homogeneously impregnated with a polymerized urethane-based compound dispersed in a liquid vehicle comprising an aprotic solvent and an alcohol. The resulting non-greening carrier matrix provides improved color resolution and increased sensitivity to proteins in dry phase test strip assays, thereby affording a more accurate and trustworthy protein assay of liquid test samples, such as urine.

Abstract: A test device and method of determining the presence and concentration of proteins in a test sample are disclosed. The test device includes a test pad comprising a new and improved carrier matrix incorporating an indicator reagent composition capable of interacting with proteins to produce a detectable or measurable response. The new and improved carrier matrix of the test pad comprises a film, membrane or layer of a polymerized urethane-based compound, a water insoluble inorganic compound and an insoluble organic compound. The carrier matrix provides improved color resolution and increased sensitivity to proteins in dry phase test strip assays, thereby achieving an accurate and trustworthy protein assay of a liquid test sample, such as urine, having a protein concentration as low as about 5 mg/dL. Also disclosed is a method of making the test device.