Abstract: Pancreatic .alpha.-amylase is determined in body fluid in the presence of salivary .alpha.-amylase by combining the body fluid with a monoclonal antibody that inhibits salivary .alpha.-amylase by 95% or more and inhibits pancreatic .alpha.-amylase by 50% or less, and then detecting pancreatic .alpha.-amylase with a system for the detection of .alpha.-amylase. The monoclonal antibody may be in immobilized form. The monoclonal antibody is preferably produced by immunizing a Balb/c mouse or an AJ mouse with a specific immunogen for a specific number of times, fusing .beta.-lymphocytes obtained from the mouse with a myeloma cell line to form an antibody producing hybridoma cell line, cloning and screening the hybridoma cell line for the desired monoclonal antibody, and isolating the monoclonal antibody. The immunogen contains modified or unmodified salivary .alpha.-amylase, aluminum hydroxide and Bortadella pertussis.

Abstract: In body fluids containing saliva alpha amylase and pancreatic alpha amylase, pancreatic alpha amylase is determined with a monoclonal antibody which specifically binds but does not inhibit saliva alpha amylase and which has a cross-reactivity of 5% or less toward pancreatic alpha amylase. The monoclonal antibody binds salvia alpha amylase to form a complex which is separated to permit determining pancreatic alpha amylase with an amylase detection system. The complex may be separated by precipitating with a precipitating agent such as an anti-antibody or protein A, or by immobilizing the monoclonal antibody on a solid carrier.

Abstract: The present invention provides a process for increasing the quantum yield in the case of the oxidation of luminol or of a 7-dialkylaminonaphthalene-1,2-dicarboxylic acid hydrazide, each alkyl radical of which contains up to 3 carbon atoms, by a peroxide compound in the presence of peroxidase ( POD), wherein the reaction is carried out in the presence of fluorescein, the concentration of the fluorescein being in a concentration range which gives a quantum yield which is greater than the sum of the quantum yields of the individual chemiluminescing materials.The present invention also provides a reagent for the determination of POD, wherein it contains luminol or a 7-dialkylaminonaphthalene-1,2-dicarboxylic acid hydrazide, each alkyl radical of which contains up to 3 carbon atoms, fluorescein, a hydrogen peroxide provider, a buffer substance (pH 7.5 to 9) and optionally a sequestering agent.

Abstract: The present invention provides a process for the preparation of compounds of the general formula: ##STR1## in which X is a hydroxyl group and X.sub.1 is a hydrogen atom or a hydroxyl group, and especially of luciferin, by the reaction of D-cysteine with 2-cyanomono- or -dihydroxybenzothiazole obtained from 2-chloromono- or -dimethoxybenzothiazole via a demethylation, wherein the demethylation is accomplished by reaction with iodotrimethylsilane or with a mixture of phenyltrimethylsilane and iodine and hydrolysis under mild conditions of the silyl derivative formed.

Abstract: The present invention provides a method for the determination of peroxidase in the presence of a compound, the enzyme-catalysed oxidation of which with a peroxy compound results in the emission of light, which is measured, wherein 7-dimethylaminonaphthalene-1,2-dicarboxylic acid hydrazide of the formula ##STR1## is used as light-emitting compound. The present invention also provides a reagent for the determination of peroxidase, comprising 7-dimethylaminonaphthalene-1,2-dicarboxylic acid hydrazide, a system providing hydrogen peroxide and a buffer substance of pH 6 to 9.

Abstract: Creatine kinase is determined by the reaction of creatine phosphate with adenosine diphosphate with the formation of adenosine triphosphate, reaction of the latter with luciferin and oxygen in the presence of luciferase and diadenosine pentaphosphate with the formation of oxyluciferin and adenosine monophosphate, and measurement of the light thereupon emitted, the reaction being performed with a saturated concentration of adenosine diphosphate and substrate, in the presence of 1 to 10 millimoles per liter of AMP at pH values of 5.8 to 7.5, with at least 50 units of luciferase per test. It is desirable to operate in the presence of diadenosine pentaphosphate or sodium fluoride and a sequestering agent.

Abstract: A method for the quantitative determination of an oxidized pyridine co-enzyme which comprises reacting a sample containing oxidized pyridine co-enzyme in the presence of its specific alcohol dehydrogenase with an aliphatic alcohol of 8 to 16 carbon atoms, oxidizing the aldehyde formed with reduced flavine mononucleotide and oxygen in the presence of luciferase and of the particular FMN-reductase which is independent of the co-enzyme to be determined and of the reduced substrate co-enzyme of the latter, and measuring the resulting light emission as a measure of the initial oxidized pyridine co-enzyme content.