Abstract: A method for the detection of occult human blood in human stool samples by immunologically determining after performing the known peroxidase procedure, a human component abnormally present in the stool.

Abstract: A solid phase-sandwich enzyme-immunoassay method for the rapid determination of carcinoembryonic antigen (CEA). The sample to be investigated is incubated with a first CEA antibody, which is bound to a water-insoluble carrier, and a second CEA antibody, to which peroxidase is bound directly or via a biotin/avidin bridge. The immunological reaction can be carried out in one or two steps. By the presence of 0.4-1.0 mol/l of phosphate ions, 0.3-0.4 mol/l of sulfate ions or 0.2-0.4 mol/l of tartrate ions in the immunological reaction or in the second step thereof (insofar as it is carried out in two steps) the incubation time period is shortened considerably. After the immunological reaction, the phases are separated, whereupon the peroxidase activity is measured either in the solid or in the liquid phase as the amount of CEA present in the sample.

Abstract: A method for the stabilization of peroxidase in a medium containing a serum or serum protein by the addition of 4-amino-antipyrine and stabilized peroxidase compositions are described.

Abstract: A method of improving the determination of acid phosphatase by adding a reagent which considerably increases the activity of the enzyme is disclosed. Also disclosed are reagent kits containing said reagent.