Abstract: A method for measuring the presence of calprotectin (S100A8/A) heterodimer in a biological sample using a particle-enhanced turbidimetric immunoassay (PETIA) based on monoclonal antibodies. The method can be adapted on automated standard analyzers and provides a reliable clinical measurement of calprotectin in faecal samples and extracts. The method is comparable to commerical two-site sandwich ELISA. The disclosed method counters spontaneous agglutination caused by calcium ions and low-molecular weight calcium-binding S100 proteins as observed with conventional PETIAs. The method can be used for measuring the presence of human calprotectin in stool, urine, serum, plasma, synovial liquid and other body liquids. Metrological traceability and high commutability with conventional immunoassays (ELISA) has been shown despite of different measurement principles used.

Abstract: A method for measuring the presence of calprotectin (S100A8/A) heterodimer in a biological sample using a particle-enhanced turbidimetric immunoassay (PETIA) based on monoclonal antibodies. The method can be adapted on automated standard analyzers and provides a reliable clinical measurement of calprotectin in faecal samples and extracts. The method is comparable to commerical two-site sandwich ELISA. The disclosed method counters spontaneous agglutination caused by calcium ions and low-molecular weight calcium-binding S100 proteins as observed with conventional PETIAs. The method can be used for measuring the presence of human calprotectin in stool, urine, serum, plasma, synovial liquid and other body liquids. Metrological traceability and high commutability with conventional immunoassays (ELISA) has been shown despite of different measurement principles used.

Abstract: A method for quantitatively determining the amount of acetaminophen in a sample with greater precision, greater sensitivity and fewer interactions and fewer spectral and chemical interferences with other compounds contained in the sample. The method includes acetaminophen being hydrolyzed and the resulting p-minophenol being reacted with a compound of general formula (III) in the presence of an oxidant, wherein R1 and R2, independently of one another, are selected from H, —CH3, and —OCH3, R3 is —C2H5 and R4 is a C1-4 alkyl moiety with a terminal sulfonate group, with the proviso that at least one of R1 and R2 is —OCH3 and/or R4 additionally has at least one OH substituent, and then the amount of the compound of general formula (IV) in the reaction mixture being photometrically determined.