Abstract: A method for determining the amount of glycated hemoglobin (HbA1c), in which—if required—the erythrocytes in a sample are hemolyzed, the haemoglobin that is then released—if required—is contacted with a proteolytic agent and the glycated hemoglobin degradation products obtained in this way or otherwise are quantified is disclosed. In order to provide such a process and reagents employable therein that has/have the property of sufficient stability of the chemical compounds that are essential to the reaction, the provision of the requisite proteolytic agent in the form of an inactivated protease is proposed, which is then only reactivated in situ.

Abstract: A method for determining the amount of glycated haemoglobin (HbA1c), in which—if required—the erythrocytes in a sample are haemolysed, the haemoglobin that is then released—if required—is contacted with a proteolytic agent and the glycated haemoglobin degradation products obtained in this way or otherwise are quantified is disclosed. In order to provide such a process and reagents employable therein that has/have the property of sufficient stability of the chemical compounds that are essential to the reaction, for the stabilization of the haemoglobin which is unfolded at a very low pH in the range from 1 to 3, at least one suitable stabilizer is present in the haemolysis solution.

Abstract: A method for determining the amount of glycated haemoglobin (HbA1c), in which—if required—the erythrocytes in a sample are haemolysed, the haemoglobin that is then released—if required—is contacted with a proteolytic agent and the glycated haemoglobin degradation products obtained in this way or otherwise are quantified is disclosed. In order to provide such a process and reagents employable therein that has/have the property of sufficient stability of the chemical compounds that are essential to the reaction, the provision of the requisite proteolytic agent in the form of an inactivated protease is proposed, which is then only reactivated in situ.

Abstract: A method for determining the amount of glycated haemoglobin (HbA1c), in which—if required—the erythrocytes in a sample are haemolysed, the haemoglobin that is then released—if required—is contacted with a proteolytic agent and the glycated haemoglobin degradation products obtained in this way or otherwise are quantified is disclosed. In order to provide such a process and reagents employable therein that has/have the property of sufficient stability of the chemical compounds that are essential to the reaction, for the stabilization of the haemoglobin which is unfolded at a very low pH in the range from 1 to 3, at least one suitable stabilizer is present in the haemolysis solution.

Abstract: By a process comprising inhibiting LDH2, LDH3, LDH4 and LDH5 in a sample with a protease in the presence of a protein-denaturating agent and then determining LDH1 remaining uninhibited, LDH1 in the sample is easily determined.

Abstract: A method for assaying biological specimens for substances contained in the components of each specimen by the use of one or more kinds of calixarenes; and a reagent comprising one or more kinds of calixarenes. The method utilizes complexes formed by calixarenes and the components of biological specimens, and makes it possible to assay biological specimens for substances contained in the components of each specimen, for example, for cholesterol contained in high-density lipoprotein (HDL), without preliminary separation from the other components of the biological specimen. The method can be conducted by easy and simple operations and lessen measurement errors or problems caused by man, and permits continuous measurement with general-purpose automatic analyzing apparatuses and multi-channel measurement together with other test items.

Abstract: The present invention relates to a method for determining a slight amount of NADH or XTP which is present in a solution, with high sensitivity by the use of an NADH kinase specific for NADH by utilizing a cycling reaction, and this method permits highly sensitive determination of NADH without any influence of NAD.sup.+ and hence is useful for diagnoses of diseases and the like.

Abstract: A glutamic-oxaloacetic transaminase (GOT) isozyme assay, which comprises selectively inhibiting s-GOT in a sample such as serum or plasma by proteinase K, optionally an excess amount of proteinase K by a protease inhibitor and then determining m-GOT remaining intact, is described.