摘要:
An enzymatic method for the analytical determination of creatine kinase in an aqueous liquid such as blood serum is described. The determination is made by measuring an optical density change using the reagents creatine phosphate, adenosine diphosphate, glycerol, glycerol kinase, .alpha.-glycerophosphate oxidase, a chromagen and a mercapto-containing creatine kinase activator. The mercapto-containing creatine kinase activator is added in encapsulated form or in low concentrations so as to preserve the activity of the chromagen.
摘要:
A process for the recovery of an intracellular enzyme from an aerobic soil microorganism is disclosed. The recovery method is carried out by(a) forming an aqueous suspension of microbial cells containing the desired intracellular enzyme,(b) disrupting the microbial cells in the suspension to release the enzyme from the cells, and(c) before, during, or after step (b) and prior to removal of disrupted microbial cells and other cellular components, introducing a water-miscible organic solvent into the suspension to form a mixture of the organic solvent and the enzyme-containing suspension.The desired enzyme is retained in the liquid phase of the mixture formed in step (c) while undesired cellular components such as other microbial cell proteins precipitate therefrom.
摘要:
Compositions and multilayer analytical elements comprising lactate oxidase which is substantially free of catalase and preferably produced by Streptococcus faecalis ATCC 12755 are provided for the quantitative analysis of lactic acid or lactate, especially in serum. The lactate oxidase catalyzes the reduction of lactic acid or lactate to pyruvate and hydrogen peroxide and the quantity of lactic acid or lactate is determined by detecting the amount of hydrogen peroxide produced. Preferably, the hydrogen peroxide is detected colorimetrically using a peroxidase-catalyzed detection system.
摘要:
An enzyme which catalyzes the hydrolysis of glycerol esters is disclosed. The enzyme is specific for alkyl esters wherein the alkyl group has from 1 to 4 carbon atoms inclusive. The enzyme is particularly useful in hydrolyzing a diacetyl glycerol ester. The enzyme is from the microorganism Bacillus subtilis ATCC No. 31954.
摘要:
A composition and element for assaying a neuraminic acid comprises a neuraminic acid aldolase, pyruvate oxidase and an electron acceptor. A sample containing a neuraminic acid can be contacted with the composition and the product detected spectrophotometrically.
摘要:
Antibodies which are specific to a thermostable DNA polymerase can be used to reduce or eliminate the formation of non-specific products in polymerase chain reaction methods. These antibodies and other temperature sensitive inhibitors are effective to inhibit DNA polymerase enzymatic activity at a certain temperature T.sub.1 which is generally below about 85.degree. C. The inhibitors are irreversibly inactivated at temperature T.sub.2 which is generally above about 40.degree. C. T.sub.2 is also greater than T.sub.1. Such inhibitors can be supplied individually or in admixture with the DNA polymerase in a diagnostic test kit suitable for PCR.
摘要:
A novel process is described for hydrolyzing protein-bound cholesterol esters such as are found in blood serum. The method comprises contacting sample containing protein-bound cholesterol esters with a compatible mixture of an enzyme preparation which demonstrates cholesterol ester hydrolase activity and, as an effector, a surfactant which is an alkyl phenoxy polyethoxy ethanol comprising a polyoxyethylene chain of less than about 20 oxyethylene units.Hydrolysis compositions comprising compatible mixtures of an enzyme preparation which demonstrates cholesterol ester hydrolase activity and an effector which is a surfactant as described are also disclosed, as are analytical elements comprising at least one layer which includes such a hydrolysis composition.
摘要:
Certain reducible compounds are useful in analytical compositions, elements and methods, e.g. for assays of bacterial cells. These compounds comprise a moiety which provides a detectable species (e.g. a dye) when released from the compound in an environment of pH 9 or less (i.e. physiological pH). Structurally, the reducible compounds are aromatic derivatives or quinones having suitable substituents which promote varying amounts of moiety release at physiological pH. When reduced at about pH 7, the preferred compounds release at least 50% of the available detectable species within 30 minutes.
摘要:
A method is described for the assay of glycerol (as either free glycerol or a fatty acid ester of glycerol) in aqueous liquids such as blood serum. The method comprises the steps ofI: contacting in the presence of an electron acceptor (a) a sample to be assayed and (b) a novel reagent composition comprising1. optionally, a lipase which hydrolyzes triglycerides to glycerol;2. glycerol kinase;3. adenosine triphosphate;4. .alpha.-glycerophosphate oxidase to produce a detectable change in the presence of triglyceride or a general positive sample; andII: detecting the occurrence of said detectable change.The lipase is included when fatty acid esters of glycerol (i.e., triglycerides) are to be detected. Free glycerol from whatever source can be detected with a composition comprising 2-4 above. According to a preferred embodiment, the electron acceptor is oxygen and the reagent composition also includes a hydrogen peroxide indicator composition, i.e., reagents which interact with hydrogen peroxide to produce a detectable product. The method can be used for assay of ATP. The method and reagent composition for performing the disclosed assays can be incorporated into a matrix of absorbent material.
摘要:
A novel process is described for hydrolyzing protein-bound triglycerides such as blood serum triglycerides comprising contacting sample containing protein-bound triglycerides with a compatible mixture of an enzyme preparation which demonstrates triglyceride hydrolase activity and, as an effector, a surfactant.Hydrolysis compositions comprising compatible mixtures of an enzyme preparation which demonstrates triglyceride hydrolase activity and an effector which is a surfactant are also described, as are analytical elements comprising at least one layer which includes a hydrolysis composition which comprises such a compatible mixture of an enzyme preparation which demonstrates triglyceride hydrolase activity and a surfactant.