1197 results about "Catalase" patented technology

A multifunctional membrane is provided. The multifunctional membrane is suitable for use in an analyte sensor. In a particular application, the multifunctional membrane may be used in connection with an amperometric biosensor, such as a transcutaneous amperometric biosensor. Some functions of the membrane are associated with properties of membrane itself, which is comprised of crosslinked polymers containing heterocyclic nitrogen groups. For example, the membrane, by virtue of its polymeric composition, may regulate the flux of an analyte to a sensor. Such regulation generally improves the kinetic performance of the sensor over a broad range of analyte concentration. Other functions of the membrane are associated with functional components, such as a superoxide-dismutating / catalase catalyst, either in the form of an enzyme or an enzyme mimic, that can be bound to the scaffold provided by the membrane. The effect of any such enzyme or enzyme mimic is to lower the concentration of a metabolite, such as superoxide and / or hydrogen peroxide, in the immediate vicinity of the sensing layer of the biosensor. Lowering the concentrations of such metabolites, which are generally deleterious to the function of the sensor, generally protects or enhances biosensor integrity and performance. The membrane is thus an important tool for use in connection with analyte sensors, amperometric sensors, biosensors, and particularly, transcutaneous biosensors. A membrane-covered sensor and a method for making same are also provided.

Conversion in vitro of X-Gly to X-alpha-hydroxy-Gly or X—NH2 (X being a peptide or any other compound having a carbonyl group capable of forming a covalent bond with glycine) is accomplished enzymatically in the presence of keto acids, or salts or esters thereof, to provide a good yield without the necessity of catalase or similar enzymatic reaction enhancers. Peptidylglycine α-amidating monooxygenase (PAM) is a preferred enzyme for catalyzing the conversion. Alternatively, peptidylglycine α-hydroxylating monooxygenase (PHM) is utilized to convert X-Gly to X-alpha-hydroxy-Gly which may be recovered, or optionally may be simultaneously or sequentially converted to an amide by either a Lewis base or action of the enzyme peptidyl α-hydroxyglycine α-amidating lyase (PAL). Both PHM and PAL are functional domains of PAM.

A method of converting hydroxymethylfurfural and is derivative species into hydroxymethylfurfural oxidation products is disclosed. The method includes contacting the hydroxymethylfurfural species in a mixture with an enzyme that oxidizes the hydroxymethylfurfural species while controlling hydrogen peroxide in the mixture. In one exemplary embodiment the enzyme is chloroperoxidase and the hydrogen peroxide is metered into the mixture to predominantly and selectively make at least one of formylfuran carboxylic acid or furan dicarboxylic acid. In another embodiment the enzyme is aryl alcohol oxidase and catalase is included in the mixture to remove unwanted hydrogen peroxide by product and the reaction predominantly makes at least one of dimethylfuran or formylfuran carboxylic acid. When the predominant product is a carboxylic acid or furan dicarboxylic acid, it can be recovered in substantially pure form by acid precipitation.