Abstract: A layered device suitable for use in the analysis of blood samples which includes a first layer of a matrix material having dispersed therein a complex of copper and a polymer containing multiple pendant carboxyl groups which selectively combines with hemoglobin and bilirubin in fluid communication with a second layer which contains a reagent system which reacts with one or more predetermined analytes in the blood sample to provide a color change.

Abstract: A new and improved test device and method of determining the presence or concentration of a predetermined analyte, such as glucose, cholesterol or occult blood, in a test sample are disclosed. The test device includes a test pad comprising a suitable carrier matrix incorporating an indicator reagent composition capable of interacting with the predetermined analyte to produce a detectable or measurable response.

Abstract: Disclosed is a method for separating biological substances, particularly hemoglobin or bilirubin, from blood plasma or serum which involves contacting the plasma or serum with a water insoluble complex of a polymer containing multiple pendant carboxyl groups and copper.

Abstract: The present invention is directed to the elimination of ascorbic acid interference in assay systems, particularly assay systems based upon oxidase-peroxidase coupled reactions. When ascorbic acid is present in a sample, it can act as a reductant thereby interfering with an assay's reagent system. The present invention eliminates this inteference by quickly oxidizing any ascorbate thereby preventing ascorbate from acting as an unwanted reductant. The ascorbate is oxidized using a dual oxidant system comprising a water soluble polymer bound to Cu.sup.+2 and an organic or inorganic oxidant such as chromate, peroxide, or a N-halo derivative. This invention is surprisingly selective and generally will not itself interfere with the assay's reagent system. Furthermore, the present invention is so fast and efficient that it can be incorporated into a convenient format, such as a conventional "dip-and-read" reagent test strip system.

Abstract: A novel compound useful in detecting leukocytes, esterase and protease in a test sample. The compound has the structure ##STR1## in which: A is an acid residue, R is lower alkyl, aryl, carboxyl, carboxyl ester, amido or cyano, R* is H or lower alkyl, and X is O, S, or NR', in which R' is H, lower alkyl or aryl.

Abstract: A novel compound useful in detecting leukocytes, esterase and protease in a test sample. The compound has the structure ##STR1## in which: A is an acid residue, R is lower alkyl, aryl, carboxyl, carboxyl ester, amido or cyano, R* is H or lower alkyl, and X is O, S, or NR', in which R' is H, lower alkyl or aryl.